Drug delivery

{{Short description|Methods for delivering drugs to target sites}} {{For|the scientific journal|Drug Delivery (journal)}} [[File:Action photo of nasal spray on a black background.jpg|thumb|A nasal spray bottle being demonstrated.]] '''Drug delivery''' involves various methods and technologies designed to transport pharmaceutical compounds to their target sites helping therapeutic effect.<ref>{{Cite web|title=Drug Delivery Systems (definition)|url=http://www.reference.md/files/D016/mD016503.html|access-date=2021-04-20|website=www.reference.md}}</ref><ref>{{Cite journal|last1=Rayaprolu|first1=Bindhu Madhavi|last2=Strawser|first2=Jonathan J.|last3=Anyarambhatla|first3=Gopal|date=2018-10-03|title=Excipients in parenteral formulations: selection considerations and effective utilization with small molecules and biologics|url=https://www.tandfonline.com/doi/full/10.1080/03639045.2018.1483392|journal=Drug Development and Industrial Pharmacy|language=en|volume=44|issue=10|pages=1565–1571|doi=10.1080/03639045.2018.1483392|pmid=29863908|s2cid=46934375|issn=0363-9045}}</ref> It involves principles related to drug preparation, route of administration, site-specific targeting, metabolism, and toxicity all aimed to optimize efficacy and safety, while improving patient convenience and compliance.<ref name=":1">{{Cite journal|last1=Tiwari|first1=Gaurav|last2=Tiwari|first2=Ruchi|last3=Sriwastawa|first3=Birendra|last4=Bhati|first4=L|last5=Pandey|first5=S|last6=Pandey|first6=P|last7=Bannerjee|first7=Saurabh K|date=2012|title=Drug delivery systems: An updated review|journal=International Journal of Pharmaceutical Investigation|volume=2|issue=1|pages=2–11|doi=10.4103/2230-973X.96920|issn=2230-973X|pmc=3465154|pmid=23071954 |doi-access=free }}</ref><ref name=":2">{{Cite journal|last1=Li|first1=Junwei|last2=Zeng|first2=Mingtao|last3=Shan|first3=Hu|last4=Tong|first4=Chunyi|date=2017-08-23|title=Microneedle Patches as Drug and Vaccine Delivery Platform|url=http://www.eurekaselect.com/152718/article|journal=Current Medicinal Chemistry|language=en|volume=24|issue=22|pages=2413–2422|doi=10.2174/0929867324666170526124053|pmid=28552053}}</ref> A key goal of drug delivery is to modify a drug's pharmacokinetics and specificity by combining it with different excipients, drug carriers, and medical devices designed to control its distribution and activity in the body.<ref name=":1" /><ref name=":0">{{Cite book|editor-last=Tekade |editor-first=Rakesh K.|title=Basic fundamentals of drug delivery|date=30 November 2018|publisher=Academic Press |isbn=978-0-12-817910-9|oclc=1078149382}}</ref><ref>{{Cite journal|last=Allen|first=T. M.|date=2004-03-19|title=Drug Delivery Systems: Entering the Mainstream|url=https://www.science.org/doi/10.1126/science.1095833|journal=Science|language=en|volume=303|issue=5665|pages=1818–1822|doi=10.1126/science.1095833|pmid=15031496|bibcode=2004Sci...303.1818A|s2cid=39013016|issn=0036-8075}}</ref> Enhancing bioavailability and prolonging duration of action are essential strategies for improving therapeutic outcomes,<ref>{{Cite journal|last1=Singh|first1=Akhand Pratap|last2=Biswas|first2=Arpan|last3=Shukla|first3=Aparna|last4=Maiti|first4=Pralay|date=2019-08-30|title=Targeted therapy in chronic diseases using nanomaterial-based drug delivery vehicles|url= |journal=Signal Transduction and Targeted Therapy|language=en|volume=4|issue=1|page=33|doi=10.1038/s41392-019-0068-3|pmid=31637012|pmc=6799838|issn=2059-3635}}</ref> particularly in chronic disease management. Additionally, some research emphasizes on improving safety for the individuals administering the medication. For example, microneedle patches have been developed for vaccines and drug delivery to minimize the risk of needlestick injuries.<ref name=":2" /><ref>{{Cite journal|last1=Kim|first1=Yeu-Chun|last2=Park|first2=Jung-Hwan|last3=Prausnitz|author3-link= Mark Prausnitz|first3=Mark R.|date=November 2012|title=Microneedles for drug and vaccine delivery|url= |journal=Advanced Drug Delivery Reviews|language=en|volume=64|issue=14|pages=1547–1568|doi=10.1016/j.addr.2012.04.005|pmc=3419303|pmid=22575858}}</ref>

Drug delivery is closely linked with dosage form and route of administration, the latter of which is sometimes considered to be part of the definition.<ref>{{Cite book|last=Nahler|first=Gerhard|chapter=D |chapter-url=https://link.springer.com/chapter/10.1007/978-3-319-50669-2_4|title=Dictionary of Pharmaceutical Medicine|publisher=Springer, Cham|year=2017|isbn=978-3-319-50669-2|page=96|doi=10.1007/978-3-319-50669-2_4}}</ref> Although the terms are often used interchangeably, they represent distinct concepts. The route of administration refers specifically to the path by which a drug enters the body,<ref>{{Cite web|date=2011-06-12|title=route of administration - definition of route of administration in the Medical dictionary - by the Free Online Medical Dictionary, Thesaurus and Encyclopedia.|url=http://medical-dictionary.thefreedictionary.com/route+of+administration|access-date=2021-04-20|archive-url=https://web.archive.org/web/20110612045450/http://medical-dictionary.thefreedictionary.com/route+of+administration|archive-date=2011-06-12}}</ref> such as oral, parenteral, or transdermal.<ref name="ReferenceA">{{Cite journal |last1=Ezike |first1=Tobechukwu Christian |last2=Okpala |first2=Ugochukwu Solomon |last3=Onoja |first3=Ufedo Lovet |last4=Nwike |first4=Chinenye Princess |last5=Ezeako |first5=Emmanuel Chimeh |last6=Okpara |first6=Osinachi Juliet |last7=Okoroafor |first7=Charles Chinkwere |last8=Eze |first8=Shadrach Chinecherem |last9=Kalu |first9=Onyinyechi Loveth |last10=Odoh |first10=Evaristus Chinonso |last11=Nwadike |first11=Ugochukwu Gideon |last12=Ogbodo |first12=John Onyebuchi |last13=Umeh |first13=Bravo Udochukwu |last14=Ossai |first14=Emmanuel Chekwube |last15=Nwanguma |first15=Bennett Chima |date=2023-06-01 |title=Advances in drug delivery systems, challenges and future directions |journal=Heliyon |language=English |volume=9 |issue=6 |article-number=e17488 |doi=10.1016/j.heliyon.2023.e17488 |doi-access=free |issn=2405-8440 |pmid=37416680|pmc=10320272 |bibcode=2023Heliy...917488E }}</ref> In contrast, the dosage form refers to the physical form in which the drug is manufactured and delivered, such as tablets, capsules, patches, inhalers or injectable solutions. These are various dosage forms and technologies which include but not limited to nanoparticles, liposomes, microneedles, and hydrogels that can be used to enhance therapeutic efficacy and safety.<ref>{{Cite journal |last1=Vargason |first1=Ava M. |last2=Anselmo |first2=Aaron C. |last3=Mitragotri |first3=Samir |date=2021-04-01 |title=The evolution of commercial drug delivery technologies |url=https://www.nature.com/articles/s41551-021-00698-w |journal=Nature Biomedical Engineering |language=en |volume=5 |issue=9 |pages=951–967 |doi=10.1038/s41551-021-00698-w |pmid=33795852 |issn=2157-846X}}</ref> The same route can accommodate multiple dosage forms; for example, the oral route may involve tablet, capsule, or liquid suspension. While the transdermal route may use a patch, gel, or cream.<ref name=":3">{{Citation|last=Jain|first=Kewal K.|title=An Overview of Drug Delivery Systems|date=2020|url=https://link.springer.com/10.1007/978-1-4939-9798-5_1|work=Drug Delivery Systems|series=Methods in Molecular Biology|volume=2059|pages=1–54|editor-last=Jain|editor-first=Kewal K.|place=New York, NY|publisher=Springer New York|language=en|doi=10.1007/978-1-4939-9798-5_1|pmid=31435914|isbn=978-1-4939-9797-8|s2cid=201275047 |access-date=2021-04-20}}</ref> Drug delivery incorporates both of these concepts while encompassing a broader scope, including the design and engineering of systems that operate within or across these routes. Common routes of administration include oral, parenteral (injected), sublingual, topical, transdermal, nasal, ocular, rectal, and vaginal. However, modern drug delivery continue to expand the possibilities of these routes through novel and hybrid approaches.<ref>{{Cite web|title=COMMON ROUTES OF DRUG ADMINISTRATION|url=https://media.lanecc.edu/users/driscolln/RT114/Medication_Administration/Intro_Pharmacology/Intro_Pharmacology8.html|access-date=2021-04-20|website=media.lanecc.edu|archive-date=2021-10-15|archive-url=https://web.archive.org/web/20211015193352/https://media.lanecc.edu/users/driscolln/RT114/Medication_Administration/Intro_Pharmacology/Intro_Pharmacology8.html}}</ref>

Since the approval of the first controlled-release formulation in the 1950s, research into new delivery systems has been progressing, as opposed to new drug development which has been declining.<ref name=":5">{{Cite journal|last=Park|first=Kinam|date=September 2014|title=Controlled drug delivery systems: Past forward and future back|url= |journal=Journal of Controlled Release|language=en|volume=190|pages=3–8|doi=10.1016/j.jconrel.2014.03.054|pmc=4142099|pmid=24794901}}</ref><ref>{{Cite journal|last1=Scannell|first1=Jack W.|last2=Blanckley|first2=Alex|last3=Boldon|first3=Helen|last4=Warrington|first4=Brian|date=March 2012|title=Diagnosing the decline in pharmaceutical R&D efficiency|url=https://www.nature.com/articles/nrd3681|journal=Nature Reviews Drug Discovery|language=en|volume=11|issue=3|pages=191–200|doi=10.1038/nrd3681|pmid=22378269|s2cid=3344476|issn=1474-1776}}</ref><ref name=":4">{{Cite web|last=ltd|first=Research and Markets|title=Pharmaceutical Drug Delivery Market Forecast to 2027 - COVID-19 Impact and Global Analysis by Route of Administration; Application; End User, and Geography|url=https://www.researchandmarkets.com/reports/5067620/pharmaceutical-drug-delivery-market-forecast-to|access-date=2021-04-24|website=www.researchandmarkets.com|language=english}}</ref> Several factors may be contributing to this shift in focus. One of the driving factors is the high cost of developing new drugs. A 2013 review found the cost of developing a delivery system was only 10% of the cost of developing a new pharmaceutical.<ref>{{Cite journal|last1=He|first1=Huining|last2=Liang|first2=Qiuling|last3=Shin|first3=Meong Cheol|last4=Lee|first4=Kyuri|last5=Gong|first5=Junbo|last6=Ye|first6=Junxiao|last7=Liu|first7=Quan|last8=Wang|first8=Jingkang|last9=Yang|first9=Victor|date=2013-12-01|title=Significance and strategies in developing delivery systems for bio-macromolecular drugs|journal=Frontiers of Chemical Science and Engineering|language=en|volume=7|issue=4|pages=496–507|doi=10.1007/s11705-013-1362-1|s2cid=97347142|issn=2095-0187}}</ref> A more recent study found the median cost of bringing a new drug to market was $985 million in 2020, but did not look at the cost of developing drug delivery systems.<ref>{{Cite journal|last1=Wouters|first1=Olivier J.|last2=McKee|first2=Martin|last3=Luyten|first3=Jeroen|date=2020-03-03|title=Estimated Research and Development Investment Needed to Bring a New Medicine to Market, 2009-2018|url= |journal=JAMA|language=en|volume=323|issue=9|pages=844–853|doi=10.1001/jama.2020.1166|pmid=32125404|pmc=7054832|issn=0098-7484}}</ref> Other factors that have potentially influenced the increase in drug delivery system development may include the increasing prevalence of both chronic and infectious diseases,<ref name=":4" /><ref>{{Cite web|last=PricewaterhouseCoopers|title=Chronic diseases and conditions are on the rise|url=https://www.pwc.com/gx/en/industries/healthcare/emerging-trends-pwc-healthcare/chronic-diseases.html|access-date=2021-04-25|website=PwC|language=en-gx}}</ref> as well as a general increased understanding of the pharmacology, pharmacokinetics, and pharmacodynamics of many drugs.<ref name=":1" />

== Current efforts == Current efforts in drug delivery are vast and include topics such as controlled-release formulations, targeted delivery, nanomedicine, drug carriers, 3D printing, and the delivery of biologic drugs.<ref name=":6">{{Cite journal|date=2019-11-01|title=Recent progress in drug delivery|url= |journal=Acta Pharmaceutica Sinica B|language=en|volume=9|issue=6|pages=1145–1162|doi=10.1016/j.apsb.2019.08.003 |doi-access=free|issn=2211-3835|last1=Li|first1=Chong|last2=Wang|first2=Jiancheng|last3=Wang|first3=Yiguang|last4=Gao|first4=Huile|last5=Wei|first5=Gang|last6=Huang|first6=Yongzhuo|last7=Yu|first7=Haijun|last8=Gan|first8=Yong|last9=Wang|first9=Yongjun|last10=Mei|first10=Lin|last11=Chen|first11=Huabing|last12=Hu|first12=Haiyan|last13=Zhang|first13=Zhiping|last14=Jin|first14=Yiguang|pmid=31867161|pmc=6900554}}</ref><ref name=":7">{{Cite web|title=Drug Delivery Systems|url=https://www.nibib.nih.gov/science-education/science-topics/drug-delivery-systems-getting-drugs-their-targets-controlled-manner|archive-url=https://web.archive.org/web/20130728194135/http://www.nibib.nih.gov/science-education/science-topics/drug-delivery-systems-getting-drugs-their-targets-controlled-manner|archive-date=July 28, 2013|access-date=2021-04-25|website=www.nibib.nih.gov}}</ref>

=== The relation between nanomaterial and drug delivery === Nanotechnology is a broad field of research and development that deals with the manipulation of matter at the atomic or subatomic level. It is used in fields such as medicine, energy, aerospace engineering, and more. One of the applications of nanotechnology is in drug delivery. This is a process by which nanoparticles are used to carry and deliver drugs to a specific area in the body. There are several advantages of using nanotechnology for drug delivery, including precise targeting of specific cells, increased drug potency, and lowered toxicity to the cells that are targeted. Nanoparticles can also carry vaccines to cells that might be hard to reach with traditional delivery methods. However, there are some concerns with the use of nanoparticles for drug delivery. Some studies have shown that nanoparticles may contribute to the development of tumors in other parts of the body. There is also growing concern that nanoparticles may have harmful effects on the environment. Despite these potential drawbacks, the use of nanotechnology in drug delivery is still a promising area for future research.<ref>J. Wang, Y. Li, G. Nie, Multifunctional biomolecule nanostructures for cancer therapy, Nat. Rev. Mat. 6 (2021) 766–783</ref>

=== Targeted delivery === Targeted drug delivery is the delivery of a drug to its target site without having an effect on other tissues.<ref>{{Cite journal|date=2017-01-01|title=Nanotechnology for the Development of Nanomedicine|url=https://www.sciencedirect.com/science/article/pii/B9780128097175000014|journal=Nanotechnology-Based Approaches for Targeting and Delivery of Drugs and Genes|language=en|pages=3–61|doi=10.1016/B978-0-12-809717-5.00001-4|last1=Tekade|first1=Rakesh K.|last2=Maheshwari|first2=Rahul|last3=Soni|first3=Namrata|last4=Tekade|first4=Muktika|last5=Chougule|first5=Mahavir B.|isbn=978-0-12-809717-5}}</ref> Interest in targeted drug delivery has grown drastically due to its potential implications in the treatment of cancers and other chronic diseases.<ref name=":8">{{Cite journal|date=2018-01-01|title=Functional stimuli-responsive polymeric network nanogels as cargo systems for targeted drug delivery and gene delivery in cancer cells|url=https://www.sciencedirect.com/science/article/pii/B9780128136690000063|journal=Design of Nanostructures for Theranostics Applications|language=en|pages=243–275|doi=10.1016/B978-0-12-813669-0.00006-3|last1=Madhusudana Rao|first1=Kummara|last2=Krishna Rao|first2=Kummari S.V.|last3=Ha|first3=Chang-Sik|isbn=978-0-12-813669-0}}</ref><ref>{{Cite journal|last1=Patra|first1=Jayanta Kumar|last2=Das|first2=Gitishree|last3=Fraceto|first3=Leonardo Fernandes|last4=Campos|first4=Estefania Vangelie Ramos|last5=Rodriguez-Torres|first5=Maria del Pilar|last6=Acosta-Torres|first6=Laura Susana|last7=Diaz-Torres|first7=Luis Armando|last8=Grillo|first8=Renato|last9=Swamy|first9=Mallappa Kumara|last10=Sharma|first10=Shivesh|last11=Habtemariam|first11=Solomon|date=December 2018|title=Nano based drug delivery systems: recent developments and future prospects|url= |journal=Journal of Nanobiotechnology|language=en|volume=16|issue=1|page=71|doi=10.1186/s12951-018-0392-8|issn=1477-3155|pmc=6145203|pmid=30231877 |doi-access=free }}</ref><ref>{{Cite journal|last1=Amidon|first1=Seth|last2=Brown|first2=Jack E.|last3=Dave|first3=Vivek S.|date=August 2015|title=Colon-Targeted Oral Drug Delivery Systems: Design Trends and Approaches|url= |journal=AAPS PharmSciTech|language=en|volume=16|issue=4|pages=731–741|doi=10.1208/s12249-015-0350-9|issn=1530-9932|pmc=4508299|pmid=26070545}}</ref> In order to achieve efficient targeted delivery, the designed system must avoid the host's defense mechanisms and circulate to its intended site of action.<ref>{{Cite journal|date=2012-07-20|title=The journey of a drug-carrier in the body: An anatomo-physiological perspective|url=https://www.sciencedirect.com/science/article/abs/pii/S0168365911009527|journal=Journal of Controlled Release|language=en|volume=161|issue=2|pages=152–163|doi=10.1016/j.jconrel.2011.09.098|issn=0168-3659|last1=Bertrand|first1=Nicolas|last2=Leroux|first2=Jean-Christophe|pmid=22001607}}</ref> A number of drug carriers have been studied to effectively target specific tissues, including liposomes, nanogels, and other nanotechnologies.<ref name=":7" /><ref name=":8" /><ref>{{Cite journal|last1=Rudokas|first1=Mindaugas|last2=Najlah|first2=Mohammad|last3=Alhnan|first3=Mohamed Albed|last4=Elhissi|first4=Abdelbary|date=2016|title=Liposome Delivery Systems for Inhalation: A Critical Review Highlighting Formulation Issues and Anticancer Applications|url= |journal=Medical Principles and Practice|language=en|volume=25|issue=2|pages=60–72|doi=10.1159/000445116|issn=1011-7571|pmc=5588529|pmid=26938856}}</ref>

=== Microneedle Patches to Deliver Drugs === Drugs are delivered via scratch size patches known as Microneedle Patches. Microneedle patches are an invention of the introduction of drugs into the skin with the help of minute needles that are not painful. The patches can deliver vaccines or medications, including insulin to diabetes patients into the blood or skin (Reinke et al., 2024).<ref>{{Cite journal |last1=Reinke |first1=Alissa |last2=Whiteside |first2=Eliza J |last3=Windus |first3=Louisa |last4=Desai |first4=Devang |last5=Stehr |first5=Emma |last6=Faraji Rad |first6=Zahra |date=2024-11-01 |title=The advantages of microneedle patches compared to conventional needle-based drug delivery and biopsy devices in medicine |url=https://www.sciencedirect.com/science/article/pii/S2667099224000161 |journal=Biomedical Engineering Advances |volume=8 |article-number=100127 |doi=10.1016/j.bea.2024.100127 |issn=2667-0992}}</ref> They are easy to use and they could make people give treatments at home. However, such patches are very expensive and not easily accessible.

=== Controlled-release formulations === Controlled or modified-release formulations are designed to deliver medications at a steady rate over time, helping maintain consistent drug levels in the bloodstream.<ref>{{Cite book |last=Perrie |first=Yvonne |title=Pharmaceutics: drug delivery and targeting |date=2012 |publisher=Pharmaceutical Press |isbn=978-0-85711-059-6 |edition=2nd ed (Online-Ausg.) |series=FASTtrack |location=London Philadelphia}}</ref> This steady release reduced how often patients need to take their medication and minimizes the ups and downs in drug concentration that can cause side effects or lower effectiveness.<ref>{{Cite journal |last1=Siepmann |first1=J |last2=Peppas |first2=N. A |date=2001-06-11 |title=Modeling of drug release from delivery systems based on hydroxypropyl methylcellulose (HPMC) |url=https://www.sciencedirect.com/science/article/abs/pii/S0169409X01001120 |journal=Advanced Drug Delivery Reviews |series=Mathematical Modeling of Controlled Drug Delivery |volume=48 |issue=2 |pages=139–157 |doi=10.1016/S0169-409X(01)00112-0 |pmid=11369079 |issn=0169-409X}}</ref> These systems often take the form of matrix tablets, osmotic pumps, and reservoir-type devices, all of which use physical or chemical barriers to regulate how the drug is released. This approach is especially useful for chronic conditions such as high blood pressure, diabetes, or chronic pain, where maintaining stable therapeutic levels is key to keeping symptoms under control.<ref>{{Cite journal |last1=Nokhodchi |first1=Ali |last2=Raja |first2=Shaista |last3=Patel |first3=Pryia |last4=Asare-Addo |first4=Kofi |date=2012-11-04 |title=The Role of Oral Controlled Release Matrix Tablets in Drug Delivery Systems |url=https://bi.tbzmed.ac.ir/Article/BI_2_20121229161645 |journal=BioImpacts |language=en |volume=2 |issue=4 |pages=175–187 |doi=10.5681/bi.2012.027 |pmid=23678458 |pmc=3648939 |issn=2228-5652}}</ref>

The concept of controlled-release medication dates back to the 1950s, when Dexedrine became the first such formulation on the market.<ref name=":5" /> This era saw the introduction of transdermal patches, which deliver drugs slowly through the skin.<ref name=":9">{{Cite journal|last1=Yun|first1=Yeon Hee|last2=Lee|first2=Byung Kook|last3=Park|first3=Kinam|date=December 2015|title=Controlled Drug Delivery: Historical perspective for the next generation|url= |journal=Journal of Controlled Release|language=en|volume=219|pages=2–7|doi=10.1016/j.jconrel.2015.10.005|pmc=4656096|pmid=26456749}}</ref> As technology progressed, new formulations were developed to match the specific properties of different drugs. Examples include long-acting depot injections for medication like antipsychotics and hormone therapies, which remain effective for weeks or even months after a single dose.<ref>{{Cite journal|last1=Lindenmayer|first1=Jean-Pierre|last2=Glick|first2=Ira D.|last3=Talreja|first3=Hiteshkumar|last4=Underriner|first4=Michael|date=July 2020|title=Persistent Barriers to the Use of Long-Acting Injectable Antipsychotics for the Treatment of Schizophrenia|journal=Journal of Clinical Psychopharmacology|language=en|volume=40|issue=4|pages=346–349|doi=10.1097/JCP.0000000000001225|pmid=32639287|s2cid=220412843 |issn=1533-712X}}</ref><ref>{{Cite journal|last=Mishell|first=D. R.|date=May 1996|title=Pharmacokinetics of depot medroxyprogesterone acetate contraception|journal=The Journal of Reproductive Medicine|volume=41|issue=5 Suppl|pages=381–390|issn=0024-7758|pmid=8725700}}</ref>

Since the late 1990s, research has increasingly turned to nanotechnology as a way to improve controlled-released drug delivery.<ref name=":5" /><ref name=":9" /> Nanoparticles, tiny carriers engineered at a molecular level, can protect drugs from being broken down too quickly in the body, improve how well they're absorbed, and deliver them directly to the tissues where they're needed. This targeted delivery not only reduces side effects but also helps patients stay on track with their treatments. These advances in nanotechnology are transforming the landscape of drug delivery and are emphasizing the importance of developing the next generation of CR systems.<ref>{{Cite journal |last1=Shivakalyani |first1=Adepu |last2=Seeram |first2=Ramakrishna |date=January 2021 |title=Controlled Drug Delivery Systems: Current Status and Future Directions |url=https://www.mdpi.com/1420-3049/26/19/5905 |journal=Molecules |language=en |volume=26 |issue=19 |doi=10.3390/molecule |doi-broken-date=1 July 2025 |doi-access=free |issn=1420-3049 |archive-url=https://web.archive.org/web/20250319104846/https://www.mdpi.com/1420-3049/26/19/5905 |archive-date=2025-03-19}}</ref>

=== Nanoparticle-based Controlled-Release === The use of nanotechnology into drug delivery has opened the door to new possibilities, particularly with the development of nanoparticle-based controlled-release systems. These systems are designed to deliver drugs more precisely and over longer periods of time helping with targeted sites and therapeutic effects.<ref>{{Cite journal |last1=Patra |first1=Jayanta Kumar |last2=Das |first2=Gitishree |last3=Fraceto |first3=Leonardo Fernandes |last4=Campos |first4=Estefania Vangelie Ramos |last5=Rodriguez-Torres |first5=Maria del Pilar |last6=Acosta-Torres |first6=Laura Susana |last7=Diaz-Torres |first7=Luis Armando |last8=Grillo |first8=Renato |last9=Swamy |first9=Mallappa Kumara |last10=Sharma |first10=Shivesh |last11=Habtemariam |first11=Solomon |last12=Shin |first12=Han-Seung |date=December 2018 |title=Nano based drug delivery systems: recent developments and future prospects |journal=Journal of Nanobiotechnology |language=en |volume=16 |issue=1 |page=71 |doi=10.1186/s12951-018-0392-8 |doi-access=free |issn=1477-3155 |pmc=6145203 |pmid=30231877}}</ref> Tiny carriers, such as liposomes, dendrimers, and polymeric nanoparticles, can hold medication and release them at controlled rates. Some are even engineered to respond to specific conditions in the body. For instance, acidic microenvironment commonly found in tumor tissues can be used to trigger drug release at the site needed. This targeted approach helps minimize side effects by limiting exposure to the rest the body. Thus, making treatment more effective.<ref>{{Cite journal |last1=Gressler |first1=Sabine |last2=Hipfinger |first2=Christina |last3=Part |first3=Florian |last4=Pavlicek |first4=Anna |last5=Zafiu |first5=Christian |last6=Giese |first6=Bernd |date=2025-02-07 |title=A systematic review of nanocarriers used in medicine and beyond — definition and categorization framework |journal=Journal of Nanobiotechnology |volume=23 |issue=1 |page=90 |doi=10.1186/s12951-025-03113-7 |doi-access=free |issn=1477-3155 |pmc=11804063 |pmid=39920688}}</ref>

Recent studies have shown the effectiveness of smart nanoparticles that respond to biological cues, such as pH or redox conditions, thereby delivering drugs more precisely to tumor sites. For instance, pH-sensitive nanoparticles take advantage of the lower pH in tumor cells to release the drugs, which boost effectiveness while protecting healthy cells.<ref>{{Cite journal |last1=Sun |first1=Leming |last2=Liu |first2=Hongmei |last3=Ye |first3=Yanqi |last4=Lei |first4=Yang |last5=Islam |first5=Rehmat |last6=Tan |first6=Sumin |last7=Tong |first7=Rongsheng |last8=Miao |first8=Yang-Bao |last9=Cai |first9=Lulu |date=2023-11-03 |title=Smart nanoparticles for cancer therapy |journal=Signal Transduction and Targeted Therapy |language=en |volume=8 |issue=1 |page=418 |doi=10.1038/s41392-023-01642-x |issn=2059-3635 |pmc=10622502 |pmid=37919282}}</ref> Additionally, the use of biocompatible materials and switching the nanoparticle surfaces have improved their accuracy and release of delivery systems.<ref>{{Cite journal |last1=Hong |first1=Liquan |last2=Li |first2=Wen |last3=Li |first3=Yang |last4=Yin |first4=Shouchun |date=2023-07-12 |title=Nanoparticle-based drug delivery systems targeting cancer cell surfaces |journal=RSC Advances |language=en |volume=13 |issue=31 |pages=21365–21382 |doi=10.1039/D3RA02969G |pmid=37465582 |pmc=10350659 |bibcode=2023RSCAd..1321365H |issn=2046-2069}}</ref>

Advances in design have also made it possible to create multi-functional nanoparticles that are capable of handling tough challenges like multi-drug resistance in cancer. These systems can carry more than one type of drug, targeting specific molecules, which helps to deliver a stronger punch to tumor tissues. Altogether, these breakthroughs point to a potential for nanoparticle-based controlled-release therapies in the fields of cancer therapy and personalized medicine.<ref>{{Cite journal |last1=Zhang |first1=Jiaxin |last2=Wang |first2=Siyuan |last3=Zhang |first3=Daidi |last4=He |first4=Xin |last5=Wang |first5=Xue |last6=Han |first6=Huiqiong |last7=Qin |first7=Yanru |date=2023-08-03 |title=Nanoparticle-based drug delivery systems to enhance cancer immunotherapy in solid tumors |journal=Frontiers in Immunology |language=English |volume=14 |article-number=1230893 |doi=10.3389/fimmu.2023.1230893 |doi-access=free |pmid=37600822 |pmc=10435760 |issn=1664-3224}}</ref>

=== Advancements in Smart Polymers and Hydrogels === In recent years, advances in smart polymers and hydrogels have brought major improvements to how drugs are delivered in controlled-released systems.<ref name="ReferenceA"/> These materials are unique in that they can respond to changes inside the body, like shifts in pH, temperature, and glucose levels, making it possible to fine-tune when and how much of a drug is released. For example, some hydrogels are designed to expand or contract based on these internal signals, which helps regulate the speed of drug release. This kind of precision helps improves therapeutic treatment and reduces side effects. These responsive materials are useful for managing chronic condition like diabetes, where glucose-responsive hydrogels can adjust insulin release based on blood sugar levels.<ref>{{Cite journal |last1=Priya James |first1=Honey |last2=John |first2=Rijo |last3=Alex |first3=Anju |last4=Anoop |first4=K. R. |date=2014-04-01 |title=Smart polymers for the controlled delivery of drugs – a concise overview |journal=Acta Pharmaceutica Sinica B |volume=4 |issue=2 |pages=120–127 |doi=10.1016/j.apsb.2014.02.005 |doi-access=free|pmid=26579373 |pmc=4590297 |issn=2211-3835}}</ref>

=== Modulated drug release and zero-order drug release === Many scientists worked to create oral formulations that could maintain a constant drug level because of the ability of drug release at a zero-order rate blood's concentration. However, a few physiological restrictions made it challenging to create such oral formulations. First, because the lower parts of the intestine have a decreased capacity for absorption, the medication absorption typically declines as an oral formulation moves from the stomach to the intestine. The decreased drug amount released from the formulation over time frequently made this condition worse. Phenylpropanolamine HCl release from was the only instance of sustaining consistent blood concentration for roughly 16 hours.<ref>J.-C. Liu, M. Farber, Y.W. Chien, Comparative release of phenylpropanolamine HCl from long-acting appetite suppressant products: Acutrim vs, Dexatrim. Drug Develop. and Indus. Pharm. 10 (1984) 1639–1661.</ref>

=== Delivery of biologic drugs === Delivering biological drugs such as peptides, proteins, antibodies, and genetic material, comes with unique challenges. Because of their large size and electrical charges, these molecules are often poorly absorbed and easily broken down by enzymes in the body.<ref name=":1" /><ref name=":3" /> To overcome these hurdles, scientists have been developing advanced delivery methods using tools like liposomes, nanoparticles, fusion proteins, and protein-based nanocages. Some strategies take inspiration from how toxins naturally enter cells by adapting those mechanisms for therapeutic use.<ref name=":1" /><ref>{{Cite journal|last=Strohl|first=William R.|date=January 2018|title=Current progress in innovative engineered antibodies|url= |journal=Protein & Cell|language=en|volume=9|issue=1|pages=86–120|doi=10.1007/s13238-017-0457-8|issn=1674-800X|pmc=5777977|pmid=28822103}}</ref><ref>{{Cite journal|last1=Marschall|first1=Andrea L J|last2=Frenzel|first2=André|last3=Schirrmann|first3=Thomas|last4=Schüngel|first4=Manuela|last5=Dübel|first5=Stefan|date=2011|title=Targeting antibodies to the cytoplasm|journal=mAbs|volume=3|issue=1|pages=3–16|doi=10.4161/mabs.3.1.14110|issn=1942-0862|pmc=3038006|pmid=21099369}}</ref><ref>{{cite journal | vauthors = Uchida M, Maier B, Waghwani HK, Selivanovitch E, Pay SL, Avera J, Yun E, Sandoval RM, Molitoris BA, Zollman A, Douglas T, Hato, T | title = The archaeal Dps nanocage targets kidney proximal tubules via glomerular filtration | journal = Journal of Clinical Investigation | volume = 129 | pages = 3941–3951 | date = September 2019 | issue = 9 | doi = 10.1172/JCI127511 | pmid = 31424427 | pmc = 6715384 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Ruschig M, Marschall Andrea LJ | title = Targeting the Inside of Cells with Biologicals: Toxin Routes in a Therapeutic Context | journal = BioDrugs | year = 2023 | volume = 37 | issue = 2 | pages = 181–203 | doi = 10.1007/s40259-023-00580-y | pmid = 36729328 | pmc = 9893211 | doi-access = free }}</ref>

Among the macromolecules studied, RNA delivery has made progress, especially with the success of RNA-based COVID-19 vaccines. While protein and DNA delivery have shown progress, proteins in live animals and DNA in lab settings, delivering these large molecules, still remain a complex task.<ref>{{Cite journal |last1=Zuris |first1=John A |last2=Thompson |first2=DB |last3=Shu |first3=Y |last4=Guilinger |first4=JP |last5=Bessen |first5=JL |last6=Hu |first6=JH |last7=Maeder |first7=ML |last8=Joung |first8=JK |last9=Chen |first9=ZY |last10=Liu |first10=DR |date=Jan 2015 |title=Cationic lipid-mediated delivery of proteins enables efficient protein-based genome editing in vitro and in vivo |journal=Nat Biotechnol |volume=33 |issue=1 |pages=73–80 |doi=10.1038/nbt.3081 |pmid=25357182 |pmc=4289409}}</ref><ref>{{Cite journal |last1=Schoenmaker |first1=Linde |last2=Witzigmann |first2=D |last3=Kulkarni |first3=JA |last4=Verbeke |first4=R |last5=Kersten |first5=G |last6=Jiskoot |first6=W |last7=Crommelin |first7=DJA |date=April 2021 |title=mRNA-lipid nanoparticle COVID-19 vaccines: Structure and stability |journal=Int J Pharm |volume=601 |article-number=120586 |doi=10.1016/j.ijpharm.2021.120586 |pmc=8032477 |pmid=33839230}}</ref><ref>{{Cite journal|last1=Marschall|first1=Andrea L J|date=October 2021|title=Targeting the Inside of Cells with Biologicals: Chemicals as a Delivery Strategy|journal=BioDrugs|volume=25|issue=6|pages=643–671|doi=10.1007/s40259-021-00500-y|pmc=8548996|pmid=34705260}}</ref> Although oral administration is generally preferred by patients for convenience, it's rarely effective for biologics due to poor absorption. That being said, innovative technologies such as enzyme inhibitors, permeation enhancers, lipid-based nanoparticles, and microneedles are being used to improve oral bioavailability for these drugs.<ref>{{cite journal|last1= Haddadzadegan |first1=S|last2= Dorkoosh |first2=F | last3=Bernkop-Schnürch|first3=A|title= Oral delivery of therapeutic peptides and proteins: Technology landscape of lipid-based nanocarriers |journal= Adv Drug Deliv Rev |date=2022|volume=182|article-number=114097 |doi=10.1016/j.addr.2021.114097|pmid=34999121|s2cid=245820799|doi-access=free}}</ref><ref>{{cite journal | vauthors = Bordbar-Khiabani A, Gasik M | title = Smart hydrogels for advanced drug delivery systems | journal = International Journal of Molecular Sciences | year = 2022 | volume = 23 | issue = 7 | page = 3665 | doi = 10.3390/ijms23073665 | pmid = 35409025 | pmc = 8998863 | doi-access = free }}</ref>

One of the recent developments that has been successful is the use of lipid nanoparticles (LNPs) to deliver messenger RNA (mRNA). LNPs protect fragile mRNA from degradation and escape from endosomes so it can reach the cytoplasm and produce proteins.<ref>{{Cite journal |last1=Hou |first1=Xucheng |last2=Zaks |first2=Tal |last3=Langer |first3=Robert |last4=Dong |first4=Yizhou |date=2021-08-10 |title=Lipid nanoparticles for mRNA delivery |journal=Nature Reviews Materials |language=en |volume=6 |issue=12 |pages=1078–1094 |doi=10.1038/s41578-021-00358-0 |issn=2058-8437 |pmc=8353930 |pmid=34394960 |bibcode=2021NatRM...6.1078H}}</ref> This delivery method gained worldwide recognition during COVID-19 pandemic with the approval of mRNA vaccines from Pfizer-BioTech and Moderna. The rapid rollout of these vaccines proved that LNPs are not only effective but also scalable for mass production and global use.<ref>{{Cite journal |last1=Pardi |first1=Norbert |last2=Hogan |first2=Michael J. |last3=Porter |first3=Frederick W. |last4=Weissman |first4=Drew |date=April 2018 |title=mRNA vaccines — a new era in vaccinology |journal=Nature Reviews Drug Discovery |language=en |volume=17 |issue=4 |pages=261–279 |doi=10.1038/nrd.2017.243 |issn=1474-1776 |pmc=5906799 |pmid=29326426}}</ref>

Looking beyond vaccines, mRNA therapies are now being explored for a range of therapeutic applications including cancer immunotherapy, genetic disorders, and other infectious diseases. Researchers are also testing alternative delivery systems, like exosomes and new types of nanoparticles, to make mRNA therapies safer and more efficient.<ref>{{Cite journal |last1=Lu |first1=Ruei-Min |last2=Hsu |first2=Hsiang-En |last3=Perez |first3=Ser John Lynon P. |last4=Kumari |first4=Monika |last5=Chen |first5=Guan-Hong |last6=Hong |first6=Ming-Hsiang |last7=Lin |first7=Yin-Shiou |last8=Liu |first8=Ching-Hang |last9=Ko |first9=Shih-Han |last10=Concio |first10=Christian Angelo P. |last11=Su |first11=Yi-Jen |last12=Chang |first12=Yi-Han |last13=Li |first13=Wen-Shan |last14=Wu |first14=Han-Chung |date=2024-09-10 |title=Current landscape of mRNA technologies and delivery systems for new modality therapeutics |journal=Journal of Biomedical Science |language=en |volume=31 |issue=1 |page=89 |doi=10.1186/s12929-024-01080-z |doi-access=free |issn=1423-0127 |pmc=11389359 |pmid=39256822}}</ref> However, challenges remain, as mRNA is highly sensitive to environmental conditions. To address this, ongoing research is expanding into new administration routes including inhalable or oral mNRA formulations. This could reduce production costs and make these therapies more accessible to the world.<ref>{{Cite journal |last1=Sahin |first1=Ugur |last2=Muik |first2=Alexander |last3=Derhovanessian |first3=Evelyna |last4=Vogler |first4=Isabel |last5=Kranz |first5=Lena M. |last6=Vormehr |first6=Mathias |last7=Baum |first7=Alina |last8=Pascal |first8=Kristen |last9=Quandt |first9=Jasmin |last10=Maurus |first10=Daniel |last11=Brachtendorf |first11=Sebastian |last12=Lörks |first12=Verena |last13=Sikorski |first13=Julian |last14=Hilker |first14=Rolf |last15=Becker |first15=Dirk |date=2020-10-22 |title=COVID-19 vaccine BNT162b1 elicits human antibody and TH1 T cell responses |journal=Nature |language=en |volume=586 |issue=7830 |pages=594–599 |doi=10.1038/s41586-020-2814-7 |pmid=32998157 |issn=0028-0836|doi-access=free }}</ref>

=== Nanoparticle drug delivery === Delivering medications to the brain has long been a significant challenge in treating neurological diseases. The main reason lies in the blood-brain barrier (BBB), a highly selective, protective layer that shields the brain from toxins and pathogens in the bloodstream. While the BBB is crucial for maintaining brain health, it also makes it difficult for most therapeutic drugs to reach their target, especially in conditions like Alzheimer's and Parkinson's disease.<ref>{{Cite journal |last=Pardridge |first=William M |date=2012-11-01 |title=Drug Transport across the Blood–Brain Barrier |journal=Journal of Cerebral Blood Flow & Metabolism |language=EN |volume=32 |issue=11 |pages=1959–1972 |doi=10.1038/jcbfm.2012.126 |issn=0271-678X |pmc=3494002 |pmid=22929442}}</ref> As a result, conventional drug delivery methods often fall short, either causing unwanted side effects or failing to deliver a high enough concentration to be effective.<ref>{{Cite journal |last1=Zha |first1=Shuai |last2=Liu |first2=Haitao |last3=Li |first3=Hengde |last4=Li |first4=Haolan |last5=Wong |first5=Ka-Leung |last6=All |first6=Angelo Homayoun |date=2024-01-23 |title=Functionalized Nanomaterials Capable of Crossing the Blood-Brain Barrier |journal=ACS Nano |volume=18 |issue=3 |pages=1820–1845 |doi=10.1021/acsnano.3c10674 |issn=1936-086X |pmc=10811692 |pmid=38193927 |bibcode=2024ACSNa..18.1820Z }}</ref>

To address this, researchers have turned to nanoparticles, tiny engineered carriers designed to sneak past the BBB and deliver drugs directly to the brain tissue These particles can be tailored to take advantage of the body's own transport systems. For example, by attaching certain molecules to their surfaces, nanoparticles can trigger receptor-mediated transcytosis, a natural process that allows them to pass through cells lining the BBB and enter the brain.<ref>{{Cite journal |last1=Jones |first1=Angela R. |last2=Shusta |first2=Eric V. |date=2007-08-01 |title=Blood–Brain Barrier Transport of Therapeutics via Receptor-Mediation |journal=Pharmaceutical Research |language=en |volume=24 |issue=9 |pages=1759–1771 |doi=10.1007/s11095-007-9379-0 |pmid=17619996 |issn=0724-8741|pmc=2685177 }}</ref><ref>{{Cite journal |last1=Tang |first1=Kaicheng |last2=Tang |first2=Zhongjie |last3=Niu |first3=Miaomiao |last4=Kuang |first4=Zuyin |last5=Xue |first5=Weiwei |last6=Wang |first6=Xinyu |last7=Liu |first7=Xinlong |last8=Yu |first8=Yang |last9=Jeong |first9=Seongdong |last10=Ma |first10=Yifan |last11=Wu |first11=Annette |last12=Kim |first12=Betty Y. S. |last13=Jiang |first13=Wen |last14=Yang |first14=Zhaogang |last15=Li |first15=Chong |date=2025-04-10 |title=Allosteric targeted drug delivery for enhanced blood-brain barrier penetration via mimicking transmembrane domain interactions |journal=Nature Communications |language=en |volume=16 |issue=1 |article-number=3410 |doi=10.1038/s41467-025-58746-x |pmid=40210849 |issn=2041-1723|pmc=11986143 |bibcode=2025NatCo..16.3410T }}</ref> This kind of targeted delivery helps reduce the drug's exposure to the rest of the body, lowering the risk of side effects and increasing concentration where it matters most. So far, this strategy has shown promise in delivering treatments to the brain for conditions like Alzheimer's and Parkinson's disease.<ref>{{Cite journal |last1=Tiwari |first1=Gaurav |last2=Tiwari |first2=Ruchi |last3=Bannerjee |first3=SaurabhK |last4=Bhati |first4=L |last5=Pandey |first5=S |last6=Pandey |first6=P |last7=Sriwastawa |first7=Birendra |date=2012 |title=Drug delivery systems: An updated review |journal=International Journal of Pharmaceutical Investigation |language=en-US |volume=2 |issue=1 |pages=2–11 |doi=10.4103/2230-973x.96920 |doi-access=free |issn=2230-973X |pmc=3465154 |pmid=23071954}}</ref><ref>{{Cite journal |last1=Hersh |first1=Andrew M. |last2=Alomari |first2=Safwan |last3=Tyler |first3=Betty M. |date=2022-04-09 |title=Crossing the Blood-Brain Barrier: Advances in Nanoparticle Technology for Drug Delivery in Neuro-Oncology |journal=International Journal of Molecular Sciences |language=en |volume=23 |issue=8 |page=4153 |doi=10.3390/ijms23084153 |doi-access=free |issn=1422-0067 |pmc=9032478 |pmid=35456971}}</ref>

Several types of nanoparticles are being studied for this purpose. Liposomes, for instance, are small vesicles that can carry drugs and be modified to circulate longer or home in on specific brain regions.<ref>{{Cite journal |last=Kreuter |first=Jörg |date=2014-05-01 |title=Drug delivery to the central nervous system by polymeric nanoparticles: What do we know? |url=https://www.sciencedirect.com/science/article/abs/pii/S0169409X13001919 |journal=Advanced Drug Delivery Reviews |series=2014 Editor's Collection |volume=71 |pages=2–14 |doi=10.1016/j.addr.2013.08.008 |pmid=23981489 |issn=0169-409X}}</ref><ref>{{Cite journal |last1=Sercombe |first1=Lisa |last2=Veerati |first2=Tejaswi |last3=Moheimani |first3=Fatemeh |last4=Wu |first4=Sherry Y. |last5=Sood |first5=Anil K. |last6=Hua |first6=Susan |date=2015-12-01 |title=Advances and Challenges of Liposome Assisted Drug Delivery |journal=Frontiers in Pharmacology |language=English |volume=6 |page=286 |doi=10.3389/fphar.2015.00286 |doi-access=free |pmid=26648870 |pmc=4664963 |issn=1663-9812}}</ref> Dendrimers, with their tree-like structure, can hold multiple drug molecules and targeting agents at once. Polymeric nanoparticles, made from biodegradable materials like polylactic acid (PLA) or polylactic-co-glycolic acid (PLGA), can be engineered to release drugs over time in a controlled way. Solid lipid nanoparticles offer another alternative, combining biocompatibility with the ability to cross barriers more efficiently. Altogether, these advances are paving the way for more effective and precise treatments for a range of neurological disorders.<ref>{{Cite journal |last1=Koo |first1=Yong-Eun Lee |last2=Reddy |first2=G. Ramachandra |last3=Bhojani |first3=Mahaveer |last4=Schneider |first4=Randy |last5=Philbert |first5=Martin A. |last6=Rehemtulla |first6=Alnawaz |last7=Ross |first7=Brian D. |last8=Kopelman |first8=Raoul |date=2006-12-01 |title=Brain cancer diagnosis and therapy with nanoplatforms |url=https://www.sciencedirect.com/science/article/abs/pii/S0169409X06001797 |journal=Advanced Drug Delivery Reviews |series=Particulate Nanomedicines |volume=58 |issue=14 |pages=1556–1577 |doi=10.1016/j.addr.2006.09.012 |pmid=17107738 |issn=0169-409X}}</ref>

Nanotechnology helps to transfer medicine to specific places in the body. Drug delivery in new forms with the assistance of minute particles, like liposomes or polymeric micelles. These particles support the drugs by preventing disintegration and enhancing functionality (Islam et al., 2025).<ref name=":10">{{Cite journal |last1=Islam |first1=Safiul |last2=Ahmed |first2=Md Mir Shakib |last3=Islam |first3=Mohammad Aminul |last4=Hossain |first4=Nayem |last5=Chowdhury |first5=Mohammad Asaduzzaman |date=2025-05-01 |title=Advances in nanoparticles in targeted drug delivery–A review |url=https://www.sciencedirect.com/science/article/pii/S2666845925001163 |journal=Results in Surfaces and Interfaces |volume=19 |article-number=100529 |doi=10.1016/j.rsurfi.2025.100529 |issn=2666-8459}}</ref> An example would be, they can distribute cancer drugs to the tumors, which reduce the side effects. Researchers also come up with particles, which release drugs when going through certain conditions like heat or light. Despite the nature of this technology, it remains expensive and needs further safety studies. In the near future researchers say there will be a more advanced strategies of treatment such as the use nanomedicine and technology like artificial intelligence (Islam et al., 2025).<ref name=":10" />

'''Drug Delivery: Developing Countries'''

The drug delivery mechanisms have the potential to enhance the health of all parts of the world despite the fact that most of the advanced systems are quite costly to the poor nations. Simple system, orals or skin patch, is more feasible in low resource countries. Most countries have used vaccines that are administered orally to combat such diseases as polio (Yenet et al., 2023).<ref>{{Cite journal |last1=Yenet |first1=Aderaw |last2=Nibret |first2=Getinet |last3=Tegegne |first3=Bantayehu Addis |date=2023-06-13 |title=Challenges to the Availability and Affordability of Essential Medicines in African Countries: A Scoping Review |url=https://www.dovepress.com/challenges-to-the-availability-and-affordability-of-essential-medicine-peer-reviewed-fulltext-article-CEOR |journal=ClinicoEconomics and Outcomes Research |language=English |volume=15 |pages=443–458 |doi=10.2147/CEOR.S413546 |doi-access=free }}</ref> The government and the hospital organizations need to collaborate in order to reduce the cost and offer the new means of drug distribution that will allow giving the new medications everywhere.

'''Ethical and Safety Issues'''

Emerging drug delivery devices such as nanoparticles or gene therapies are highly dangerous in terms of safety and equity. For example, we should make sure that the treatments would not negatively affect the environment or cause any incidental side effects. The regulation of other agencies such as FDA are applied in the process of ensuring the safety of new practices but vary across countries (World Health Organization, 2024).<ref>{{Cite web |title=Largest number of regulatory agencies for medical products approved as WHO Listed Authorities |url=https://www.who.int/news/item/20-05-2024-largest-number-of-regulatory-agencies-for-medical-products-approved-as-who-listed-authorities |access-date=2025-10-15 |website=www.who.int |language=en}}</ref> The government has the mandate of making sure that medicine is not only affordable to the wealthy members of the society, but also to the vulnerable ones as well.

The issue of drug delivery has raised a number of ethical concerns with respect to patients and healthcare systems. One common concern is the accessibility of specific medications within a health organization. Advanced delivery systems such as gene therapies, nanoparticles, or implants have been costly, and therefore, only patients within wealthy countries can afford them. This indicates that healthcare no longer considers equality and fairness. Another ethical concern is the issue of privacy. Digital tools have been used to determine and track patient medical adherence. Although these tools may help improve patient welfare, they may also be used to expose patient data, and there are increasing insecurities regarding patients' personal information.

== References == {{Reflist}}

== External links == * [http://pubs.acs.org/cen/coverstory/8034/8034drugdelivery.html Article in Chemical and Engineering News]

Category:Medical equipment