Two medicines, side by side
Gentamicin vs erythromycin
Gentamicin and erythromycin are both labeled for bacterial infections. Drugs@FDA records approvals of gentamicin since 1970 and of erythromycin since 1964. Pharmacies paid $1.30 per mL (Gentamicin 80 mg/2 mL vial) and $1.96 per erythromycin 250 mg tablet (NADAC, October 7, 2026); the strengths differ, so the two prices are not like for like. In FDA's classes, gentamicin is an aminoglycoside antibacterial and erythromycin a macrolide.
Check it at the source: the gentamicin FDA label on DailyMed (effective July 22, 2024); the erythromycin FDA label on DailyMed (effective August 1, 2024).
Highlights of the gentamicin record
Gentamicin (Garamycin) · label of July 22, 2024
Used for
From the label: indicationsGentamicin sulfate ophthalmic solution is indicated in the topical treatment of ocular bacterial infections including conjunctivitis, keratitis, keratoconjunctivitis, corneal ulcers, blepharitis, blepharoconjunctivitis, acute meibomianitis, and dacryocystitis, caused by susceptible strains of the following microorganisms: Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pyogenes, Streptococcus pneumoniae, Enterobacter aerogenes, Escherichia coli, Haemophilus influenzae, Klebsiella pneumoniae, Neisseria gonorrhoeae, Pseudomonas aeruginosa, and Serratia marcescens. […]
On the market
- Earliest approval on file
- June 19, 1970
- Generic labelers
- 24 labelers
- Pharmacy cost
- $1.30 per mL
Supply and safety
- Shortage
- No current entry
- Recalls
- 9
Highlights of the erythromycin record
Erythromycin (Erythrocin) · label of August 1, 2024
Used for
From the label: indicationsTo reduce the development of drug-resistant bacteria and maintain the effectiveness of erythromycin tablets and other antibacterial drugs, erythromycin tablets should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. […]
On the market
- Earliest approval on file
- June 25, 1964
- Generic labelers
- 38 labelers
- Pharmacy cost
- $1.96 per tablet
Supply and safety
- Shortage
- No current entry
- Recalls
- 2
Source: FDA drug labels via openFDA (Gentamicin label of July 22, 2024, Erythromycin label of August 1, 2024); NDC Directory, Drugs@FDA, NADAC, FDA shortages and recalls (October 8, 2026)
How do gentamicin and erythromycin differ on the record?
In FDA's classes, gentamicin is an aminoglycoside antibacterial and erythromycin a macrolide.
Generics: gentamicin since 1966; erythromycin since 1964 (Drugs@FDA).
| Gentamicin | Erythromycin | |
|---|---|---|
| Labeled for | Bacterial infections | Bacterial infections, Acne |
| Pharmacologic class | Aminoglycoside Antibacterial | Macrolide, Macrolide Antimicrobial |
| How it works (label) | n/a | n/a |
| Half-life (label) | n/a | n/a |
| Earliest approval on file (Drugs@FDA) | June 19, 1970 | June 25, 1964 |
| First generic approved | March 15, 1966 | June 24, 1964 |
| Generic labelers (NDC) | 24 labelers | 38 labelers |
| Pharmacy cost (NADAC, each one's most listed form; strengths differ) | $1.30 per mL (Gentamicin 80 mg/2 mL vial) | $1.96 per tablet (Erythromycin 250 mg tablet) |
| 12-month price change | -21% | +12% |
| Boxed warning | No | No |
| Shortage now | No current entry | No current entry |
| Recalls recorded | 9 | 2 |
| FAERS reports (a report is not proof of cause; counts follow how widely a medicine is used) | 15,709 | 18,956 |
| DEA schedule | none | none |
Source: Drugs@FDA, FDA NDC Directory, CMS NADAC of October 7, 2026, FDA shortages and recalls, FAERS via openFDA (FDA files October 8, 2026)
What next?
- Alternatives to gentamicin
- every medicine labeled for the same conditions