Neomycin

{{Short description|Type of antibiotic}} {{Use dmy dates|date=August 2025}} {{cs1 config|name-list-style=vanc|display-authors=6}} {{Infobox drug | Verifiedfields = changed | Watchedfields = changed | verifiedrevid = 462259305 | IUPAC_name = (2''RS'',3''S'',4''S'',5''R'')-5-Amino-2-(aminomethyl)-6-((2''R'',3''S'',4''R'',5''S'')-5-((1''R'',2''R'',5''R'',6''R'')-3,5-diamino-2-((2''R'',3''S'',4''R'',5''S'')-3-amino-6-(aminomethyl)-4,5-dihydroxytetrahydro-2''H''-pyran-2-yloxy)-6-hydroxycyclohexyloxy)-4-hydroxy-2-(hydroxymethyl)tetrahydrofuran-3-yloxy)tetrahydro-2''H''-pyran-3,4-diol | image = Neomycin B C.svg | image_class = skin-invert-image | image2 = Neomycin ball-and-stick.png | image_class2 = bg-transparent  | tradename = Neo-rx | Drugs.com = {{drugs.com|monograph|neomycin-sulfate}} | MedlinePlus = a682274 | pregnancy_US = D | legal_US = Rx-only | legal_US_comment = but OTC in Neosporin and similar ointments | routes_of_administration = Topical, oral  | bioavailability = None | protein_bound = N/A | metabolism = N/A | elimination_half-life = 2 to 3 hours  | CAS_number_Ref = {{cascite|correct|??}} | CAS_number = 1404-04-2 | ATC_prefix = A01 | ATC_suffix = AB08 | ATC_supplemental = {{ATC|A07|AA01}}, {{ATC|B05|CA09}}, {{ATC|D06|AX04}}, {{ATC|J01|GB05}}, {{ATC|R02|AB01}}, {{ATC|S01|AA03}}, {{ATC|S02|AA07}}, {{ATC|S03|AA01}} | PubChem = 8378 | IUPHAR_ligand = 709 | DrugBank_Ref = {{drugbankcite|correct|drugbank}} | DrugBank = DB00994 | ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}} | ChemSpiderID = 8075 | UNII_Ref = {{fdacite|correct|FDA}} | UNII = I16QD7X297 | KEGG_Ref = {{keggcite|correct|kegg}} | KEGG = D08260 | ChEBI_Ref = {{ebicite|correct|EBI}} | ChEBI = 7508 | ChEMBL_Ref = {{ebicite|changed|EBI}} | ChEMBL = 449118 | synonyms =  | C=23 | H=46 | N=6 | O=13 | smiles = O([C@H]3[C@H](O[C@@H]2O[C@H](CO)[C@@H](O[C@H]1O[C@@H](CN)[C@@H](O)[C@H](O)[C@H]1N)[C@H]2O)[C@@H](O)[C@H](N)C[C@@H]3N)[C@H]4O[C@@H]([C@@H](O)[C@H](O)[C@H]4N)CN | StdInChI_Ref = {{stdinchicite|changed|chemspider}} | StdInChI = 1S/C23H46N6O13/c24-2-7-13(32)15(34)10(28)21(37-7)40-18-6(27)1-5(26)12(31)20(18)42-23-17(36)19(9(4-30)39-23)41-22-11(29)16(35)14(33)8(3-25)38-22/h5-23,30-36H,1-4,24-29H2/t5-,6+,7+,8?,9+,10+,11-,12+,13+,14-,15+,16-,17+,18-,19+,20-,21+,22-,23-/m0/s1 | StdInChIKey_Ref = {{stdinchicite|changed|chemspider}} | StdInChIKey = PGBHMTALBVVCIT-DPNHOFNISA-N }}

'''Neomycin''', also known as '''framycetin''', is an aminoglycoside antibiotic that displays bactericidal activity against Gram-negative aerobic bacilli and some anaerobic bacilli where resistance has not yet arisen. It is generally not effective against Gram-positive bacilli and anaerobic Gram-negative bacilli. Neomycin comes in oral and topical formulations, including creams, ointments, and eyedrops. Neomycin belongs to the aminoglycoside class of antibiotics that contain two or more amino sugars connected by glycosidic bonds.

Neomycin was discovered in 1949 by microbiologist Selman Waksman and his student Hubert Lechevalier at Rutgers University. Neomycin received approval for medical use in 1952.<ref name=Fis2006>{{cite book | vauthors = Fischer J, Ganellin CR |title=Analogue-based Drug Discovery |date=2006 |publisher=John Wiley & Sons |isbn=9783527607495 |page=507 |url=https://books.google.com/books?id=FjKfqkaKkAAC&pg=PA507 |language=en |access-date=25 May 2020 |archive-date=1 August 2020 |archive-url=https://web.archive.org/web/20200801185612/https://books.google.com/books?id=FjKfqkaKkAAC&pg=PA507 |url-status=live }}</ref> Rutgers University was granted the patent for neomycin in 1957.<ref>{{Cite patent | country = US | number = 2799620 | title = Neomycin and process of preparation | inventor = Waksman SA, Lechevalier HA | assign1 = Rutgers Research and Educational Foundation | gdate = 18 July 1957 | postscript = . }}</ref>

==Discovery== Neomycin was discovered in 1949 by the microbiologist Selman Waksman and his student Hubert Lechevalier at Rutgers University. It is produced naturally by the bacterium ''Streptomyces fradiae''.<ref>{{cite web|url=http://nobelprize.org/nobel_prizes/medicine/laureates/1952/waksman-bio.html|title=The Nobel Prize in Physiology or Medicine 1952|publisher=Nobel Foundation|access-date=29 October 2008|archive-date=19 June 2018|archive-url=https://web.archive.org/web/20180619213821/https://www.nobelprize.org/nobel_prizes/medicine/laureates/1952/waksman-bio.html|url-status=live}}</ref> Synthesis requires specific nutrient conditions in either stationary or submerged aerobic conditions. The compound is then isolated and purified from the bacterium.<ref>{{cite book | chapter = Neomycin | title = Pharmaceutical Manufacturing Encyclopedia | edition = 3rd | volume = 3 | date = 2007 | pages = 2415–2416 }}</ref>

==Medical uses== Neomycin is typically applied as a topical preparation, such as Neosporin (neomycin/polymyxin B/bacitracin). The antibiotic can also be administered orally, in which case it is usually combined with other antibiotics. Neomycin is not absorbed from the gastrointestinal tract and has been used as a preventive measure for hepatic encephalopathy and hypercholesterolemia. By killing bacteria in the intestinal tract, Neomycin keeps ammonia levels low and prevents hepatic encephalopathy. Due to its poor GI tract absorption, orally administered neomycin has also been used to reduce the risk of post operative infection following gastrointestinal surgery.<ref>{{cite journal | pmc=3686946 | date=2002 | last1=Lewis | first1=R. T. | title=Oral versus systemic antibiotic prophylaxis in elective colon surgery: A randomized study and meta-analysis send a message from the 1990s | journal=Canadian Journal of Surgery. Journal Canadien de Chirurgie | volume=45 | issue=3 | pages=173–180 | pmid=12067168 }}</ref>

Waksman and Lechevalier originally noted that neomycin was active against streptomycin-resistant bacteria as well as ''Mycobacterium tuberculosis'', the causative agent for tuberculosis.<ref name="Waksman_1949b" /> Neomycin has also been used to treat small intestinal bacterial overgrowth. Neomycin is not administered via injection, as it is extremely nephrotoxic (damaging to kidney function) even when compared to other aminoglycosides. The exception is when neomycin is included, in small quantities, as a preservative in some vaccines – typically 25 μg per dose.<ref>{{cite journal | vauthors = Heidary N, Cohen DE | title = Hypersensitivity reactions to vaccine components | journal = Dermatitis | volume = 16 | issue = 3 | pages = 115–20 | date = September 2005 | pmid = 16242081 | doi = 10.1097/01206501-200509000-00004 | s2cid = 31248441 }}</ref>

In 2023, the combination of neomycin with dexamethasone and polymyxin B was the 260th most commonly prescribed medication in the United States, with more than 1{{nbsp}}million prescriptions.<ref>{{cite web | title=The Top 300 of 2023 | url=https://clincalc.com/DrugStats/Top300Drugs.aspx | website=ClinCalc | access-date=17 August 2025 | archive-date=17 August 2025 | archive-url=https://web.archive.org/web/20250817043812/https://clincalc.com/DrugStats/Top300Drugs.aspx | url-status=live }}</ref><ref>{{cite web | title = Dexamethasone; Neomycin; Polymyxin B Drug Usage Statistics, United States, 2014 - 2023 | website = ClinCalc | url = https://clincalc.com/DrugStats/Drugs/DexamethasoneNeomycinPolymyxinB | access-date = 17 August 2025 }}</ref>

===Spectrum=== Similar to other aminoglycosides, neomycin has excellent activity against Gram-negative bacteria and is partially effective against Gram-positive bacteria. It is relatively toxic to humans, with allergic reactions noted as a common adverse reaction (see: hypersensitivity).<ref>{{DermNet|dermatitis/neomycin-allergy}}</ref> Physicians sometimes recommend using antibiotic ointments without neomycin, such as Polysporin.<ref>{{cite web |url=http://www.dermadoctor.com/article_Your-Medicine-Cabinet_43.html |title=Your Medicine Cabinet |publisher=DERMAdoctor.com, Inc. |access-date=19 October 2008 |url-status=dead |archive-url=https://web.archive.org/web/20090709093022/http://www.dermadoctor.com/article_Your-Medicine-Cabinet_43.html |archive-date=9 July 2009}}</ref> The following represents minimum inhibitory concentration (MIC) susceptibility data for a few medically significant Gram-negative bacteria.<ref>{{cite web |url=http://www.toku-e.com/Assets/MIC/Neomycin%20sulfate%20EP.pdf |title=Neomycin sulfate, EP Susceptibility and Minimum Inhibitory Concentration (MIC) Data |publisher=TOKU-E |access-date=31 March 2014 |archive-date=22 December 2015 |archive-url=https://web.archive.org/web/20151222095539/http://www.toku-e.com/Assets/MIC/Neomycin%20sulfate%20EP.pdf |url-status=live }}</ref> * ''Enterobacter cloacae'': >16 μg/ml * ''Escherichia coli'': 1 μg/ml * ''Proteus vulgaris'': 0.25 μg/ml

==Side effects== In 2005–06, Neomycin was the fifth-most-prevalent allergen in patch test results (10.0%).<ref>{{cite journal | vauthors = Zug KA, Warshaw EM, Fowler JF, Maibach HI, Belsito DL, Pratt MD, Sasseville D, Storrs FJ, Taylor JS, Mathias CG, Deleo VA, Rietschel RL, Marks J | display-authors = 6 | title = Patch-test results of the North American Contact Dermatitis Group 2005-2006 | journal = Dermatitis | volume = 20 | issue = 3 | pages = 149–60 | year = 2009 | pmid = 19470301 | doi = 10.2310/6620.2009.08097 | s2cid = 24088485 }}</ref> It was named Allergen of the Year in 2010.<ref>McNamara, Damian. (2010). [http://www.edermatologynews.com/shared/shared-articles/neomycin-is-named-contact-allergen-of-the-year/4d105dda2788039dae9d166eac96393b.html Neomycin Is Named Contact Allergen of the Year] {{Webarchive|url=https://archive.today/20150422003106/http://www.edermatologynews.com/shared/shared-articles/neomycin-is-named-contact-allergen-of-the-year/4d105dda2788039dae9d166eac96393b.html|date=22 April 2015}}</ref> Neomycin is also a known GABA ''gamma''-Aminobutyric acid antagonist and can be responsible for seizures and psychosis.<ref name="pmid219730">{{cite journal | vauthors = Lee C, de Silva AJ | title = Interaction of neuromuscular blocking effects of neomycin and polymyxin B | journal = Anesthesiology | volume = 50 | issue = 3 | pages = 218–20 | date = March 1979 | pmid = 219730 | doi = 10.1097/00000542-197903000-00010 | s2cid = 13551808 }}</ref> Like other aminoglycosides, neomycin has been shown to be ototoxic, causing tinnitus, hearing loss, and vestibular problems in a small number of patients. Neomycin affects the cochlea, which is found in the inner ear.<ref name="Langman, A 1994">Langman, A. Neomycin ototoxicity. Otolaryngology Head and Neck Surgery 1994, 110, 441-444.</ref> Hearing loss is caused by ear hair cell death, which occurs in response to treatment with neomycin.<ref name="Langman, A 1994"/> Patients with existing tinnitus or sensorineural hearing loss are advised to speak with a healthcare practitioner about the risks and side effects prior to taking this medication.{{citation needed|date=March 2023}}

==Molecular biology==

===Activity=== Neomycin's antibacterial activity stems from its binding to the 30S subunit of the prokaryotic ribosome, where it inhibits prokaryotic translation of mRNA.<ref>{{cite journal | vauthors = Mehta R, Champney WS | title = Neomycin and paromomycin inhibit 30S ribosomal subunit assembly in Staphylococcus aureus | journal = Current Microbiology | volume = 47 | issue = 3 | pages = 237–43 | date = September 2003 | pmid = 14570276 | doi = 10.1007/s00284-002-3945-9 | s2cid = 23170091 }}</ref>

Neomycin also exhibits a high binding affinity for phosphatidylinositol 4,5-bisphosphate (PIP2), a phospholipid component of cell membranes.<ref name="pmid2537103">{{cite journal | vauthors = Gabev E, Kasianowicz J, Abbott T, McLaughlin S | title = Binding of neomycin to phosphatidylinositol 4,5-bisphosphate (PIP2) | journal = Biochimica et Biophysica Acta (BBA) - Biomembranes | volume = 979 | issue = 1 | pages = 105–12 | date = February 1989 | pmid = 2537103 | doi = 10.1016/0005-2736(89)90529-4 }}</ref>

===Resistance=== Neomycin resistance is conferred by either one of two kanamycin kinase genes.<ref>{{cite web |url= http://www.bio.net/bionet/mm/methods/1999-March/073912.html |title= G418/neomycin-cross resistance? |access-date= 19 October 2008 |archive-date= 25 June 2009 |archive-url= https://web.archive.org/web/20090625211444/http://www.bio.net/bionet/mm/methods/1999-March/073912.html |url-status= live }}</ref> Genes conferring neomycin-resistance are commonly included in DNA plasmids used to establish stable mammalian cell lines expressing cloned proteins in culture. Many commercially available protein expression plasmids contain a ''neo''-resistance gene as a selectable marker. Currently, research is being performed to understand if derivatives of neomycin have the same antibiotic effects while still being effective against neomycin-resistant bacteria.<ref>Bera, S.; Zhanel, G.; Schweizer, F. Design, Synthesis, and Antibacterial Activities of Neomycin−Lipid Conjugates: Polycationic Lipids with Potent Gram-Positive Activity | Journal of Medicinal Chemistry. Journal of Medicinal Chemistry 2003, 51, 6160-6164.</ref>

==Biosynthetic pathway== Neomycin was first isolated from the ''Streptomyces fradiae'' and ''Streptomyces albogriseus'' in 1949 (NBRC 12773).<ref name = "Waksman_1949">{{cite journal | vauthors = Waksman SA, Lechevalier HA, Harris DA | title = Neomycin—Production and Antibiotic Properties 123 | journal = The Journal of Clinical Investigation | volume = 28 | issue = 5 Pt 1 | pages = 934–9 | date = September 1949 | pmid = 16695766 | pmc = 438928 | doi = 10.1172/JCI102182 }}</ref> Neomycin is a mixture of neomycin B (framycetin); and its epimer neomycin C, the latter component accounting for some 5–15% of the mixture. It is a basic compound that is most active with an alkaline reaction.<ref name="Waksman_1949b" /> It is also thermostable and soluble in water (while insoluble in organic solvents).<ref name="Waksman_1949b">{{cite journal | vauthors = Waksman SA, Lechevalier HA | title = Neomycin, a New Antibiotic Active against Streptomycin-Resistant Bacteria, including Tuberculosis Organisms | journal = Science | location = New York, N.Y. | volume = 109 | issue = 2830 | pages = 305–7 | date = March 1949 | pmid = 17782716 | doi = 10.1126/science.109.2830.305 | bibcode = 1949Sci...109..305W }}</ref> Neomycin has good activity against Gram-positive and Gram-negative bacteria, but is ototoxic. Its use is thus restricted to the oral treatment of intestinal infections.<ref>{{cite book | vauthors = Dewick M |title=Medicinal natural products: a biosynthetic approach|date=March 2009|publisher=John Wiley and Sons Ltd. |location=The Atrium, Southern Gate, Chichester, West Sussex, United Kingdom |isbn=978-0-470-74168-9 |pages=508, 510, 511 |edition=3rd }}</ref>

Neomycin B is composed of four linked moieties: D-neosamine, 2-deoxystreptamine (2-DOS), D-ribose, and L-neosamine.{{citation needed|date=March 2023}}

Neomycin A, also called neamine, contains D-neosamine and 2-deoxystreptamine. Six genes are responsible for neamine biosynthesis: DOIS gene (btrC, neo7); L-glutamine:DOI aminotransferase gene (btrS, neo6); a putative glycosyltransferase gene (btrM, neo8); a putative aminotransferase (similar to glutamate-1-semialdehyde 2,1-aminomutase) gene (btrB, neo18); a putative alcohol dehydrogenase gene (btrE, neo5); and another putative dehydrogenase (similar to chorine dehydrogenase and related flavoproteins) gene (btrQ, neo11).<ref>{{cite journal | vauthors = Kudo F, Yamamoto Y, Yokoyama K, Eguchi T, Kakinuma K | title = Biosynthesis of 2-deoxystreptamine by three crucial enzymes in Streptomyces fradiae NBRC 12773 | journal = The Journal of Antibiotics | volume = 58 | issue = 12 | pages = 766–74 | date = December 2005 | pmid = 16506694 | doi = 10.1038/ja.2005.104 | doi-access = free }}</ref> A deacetylase acting to remove the acetyl group on N-acetylglucosamine moieties of aminoglycoside intermediates (Neo16) remains to be clarified (sequence similar to BtrD).<ref>{{cite journal | vauthors = Park JW, Park SR, Nepal KK, Han AR, Ban YH, Yoo YJ, Kim EJ, Kim EM, Kim D, Sohng JK, Yoon YJ | display-authors = 6 | title = Discovery of parallel pathways of kanamycin biosynthesis allows antibiotic manipulation | journal = Nature Chemical Biology | volume = 7 | issue = 11 | pages = 843–52 | date = October 2011 | pmid = 21983602 | doi = 10.1038/nchembio.671 }}</ref>

Next is the attachment of the D-ribose via ribosylation of neamine, using 5-phosphoribosyl-1-diphosphate (PRPP) as the ribosyl donor (BtrL, BtrP);<ref>{{cite journal | vauthors = Kudo F, Fujii T, Kinoshita S, Eguchi T | title = Unique O-ribosylation in the biosynthesis of butirosin | journal = Bioorganic & Medicinal Chemistry | volume = 15 | issue = 13 | pages = 4360–8 | date = July 2007 | pmid = 17482823 | doi = 10.1016/j.bmc.2007.04.040 }}</ref> glycosyltransferase (potential homologues RibF, LivF, Parf) gene (Neo15).<ref>{{cite journal | vauthors = Fan Q, Huang F, Leadlay PF, Spencer JB | title = The neomycin biosynthetic gene cluster of Streptomyces fradiae NCIMB 8233: genetic and biochemical evidence for the roles of two glycosyltransferases and a deacetylase | journal = Organic & Biomolecular Chemistry | volume = 6 | issue = 18 | pages = 3306–14 | date = September 2008 | pmid = 18802637 | doi = 10.1039/B808734B | s2cid = 29942953 }}</ref>

Neosamine B (L-neosamine B) is most likely biosynthesized in the same manner as the neosamine C (D-niosamine) in neamine biosynthesis, but with an additional epimerization step required to account for the presence of the epimeric neosamine B in neomycin B.<ref>{{cite journal | vauthors = Llewellyn NM, Spencer JB | title = Biosynthesis of 2-deoxystreptamine-containing aminoglycoside antibiotics | journal = Natural Product Reports | volume = 23 | issue = 6 | pages = 864–74 | date = December 2006 | pmid = 17119636 | doi = 10.1039/B604709M }}</ref>

thumb|Neomycin B Neomycin B and C are 23-carbon molecules with a four-ring structure. Three of the rings are six-membered, and one is five-membered.<ref name="pubchem.ncbi.nlm.nih.gov">National Center for Biotechnology Information Neomycin. https://pubchem.ncbi.nlm.nih.gov/compound/8378 (accessed 5 November 2023).</ref> Neomycin B and Neomycin C are stereoisomers of each other and differ by only one stereocenter one giving the R conformation and the other giving the S conformation.<ref name="pubchem.ncbi.nlm.nih.gov"/> Neomycin C can undergo enzymatic synthesis from ribostamycin.<ref name="pmid19713992">{{cite journal | vauthors = Kudo F, Kawashima T, Yokoyama K, Eguchi T | title = Enzymatic preparation of neomycin C from ribostamycin | journal = The Journal of Antibiotics | volume = 62 | issue = 11 | pages = 643–6 | date = November 2009 | pmid = 19713992 | doi = 10.1038/ja.2009.88 | doi-access = free }}</ref>

==Composition== Standard grade neomycin is composed of several related compounds including neomycin A (neamine), neomycin B (framycetin), neomycin C, and a few minor compounds found in much lower quantities. Neomycin B is the most active component in neomycin followed by neomycin C and neomycin A. Neomycin A is an inactive degradation product of the C and B isomers.<ref>{{cite book | vauthors = Cammack R, Attwood TK, Campbell PN, Parish JH, Smith AD, Stirling JL, Vella F | title = Oxford Dictionary of Biochemistry and Molecular Biology | edition = 2nd | chapter = neomycin | publisher = Oxford University Press | date = 2006 | pages = 453 }}</ref> The quantities of these components in neomycin vary from lot-to-lot depending on the manufacturer and manufacturing process.<ref>{{cite journal | vauthors = Tsuji K, Robertson JH, Baas R, McInnis DJ | title = Comparative study of responses to neomycins B and C by microbiological and gas-liquid chromatographic assay methods | journal = Applied Microbiology | volume = 18 | issue = 3 | pages = 396–8 | date = September 1969 | pmid = 4907002 | pmc = 377991 | doi = 10.1128/AEM.18.3.396-398.1969 }}</ref>

==DNA binding== Aminoglycosides such as neomycin are known for their ability to bind to duplex RNA with high affinity.<ref>{{cite journal | vauthors = Jin Y, Watkins D, Degtyareva NN, Green KD, Spano MN, Garneau-Tsodikova S, Arya DP | title = Arginine-linked neomycin B dimers: synthesis, rRNA binding, and resistance enzyme activity | journal = MedChemComm | volume = 7 | issue = 1 | pages = 164–169 | date = January 2016 | pmid = 26811742 | pmc = 4722958 | doi = 10.1039/C5MD00427F }}</ref> The association constant for neomycin with A-site RNA is in the 109 M−1 range.<ref>{{cite journal | vauthors = Kaul M, Pilch DS | title = Thermodynamics of aminoglycoside-rRNA recognition: the binding of neomycin-class aminoglycosides to the A site of 16S rRNA | journal = Biochemistry | volume = 41 | issue = 24 | pages = 7695–706 | date = June 2002 | pmid = 12056901 | doi = 10.1021/bi020130f }}</ref> However, more than 50 years after its discovery, its DNA-binding properties were still unknown. Neomycin has been shown to induce thermal stabilization of triplex DNA, while having little or almost no effect on the B-DNA duplex stabilization.<ref>{{cite journal | vauthors = Arya DP, Coffee RL | title = DNA triple helix stabilization by aminoglycoside antibiotics | journal = Bioorganic & Medicinal Chemistry Letters | volume = 10 | issue = 17 | pages = 1897–9 | date = September 2000 | pmid = 10987412 | doi = 10.1016/S0960-894X(00)00372-3 }}</ref> Neomycin was also shown to bind to structures that adopt an A-form structure, triplex DNA being one of them. Neomycin also includes DNA:RNA hybrid triplex formation.<ref>{{cite journal | vauthors = Arya DP, Coffee RL, Charles I | title = Neomycin-induced hybrid triplex formation | journal = Journal of the American Chemical Society | volume = 123 | issue = 44 | pages = 11093–4 | date = November 2001 | pmid = 11686727 | doi = 10.1021/ja016481j | bibcode = 2001JAChS.12311093A }}</ref>

== References == {{Reflist}}

{{Stomatological preparations}} {{Antidiarrheals, intestinal anti-inflammatory and anti-infective agents}} {{Antibiotics and chemotherapeutics for dermatological use}} {{Protein synthesis inhibitor antibiotics}} {{Throat preparations}} {{Otologicals}} {{Portal bar | Medicine}} {{Authority control}}

Category:Aminoglycoside antibiotics Category:Cell culture reagents Category:DNA-binding substances Category:Otologicals Category:Over-the-counter drugs in the United States Category:Antibiotics