Two medicines, side by side
Erythromycin vs doxycycline
Erythromycin and doxycycline are both labeled for bacterial infections and acne. Drugs@FDA records approvals of erythromycin since 1964 and of doxycycline since 1967. Pharmacies paid $1.96 per erythromycin 250 mg tablet and $0.118 per doxycycline hyclate 100 mg tablet (NADAC, October 7, 2026); the strengths differ, so the two prices are not like for like. Doxycycline's other strengths are brand-only: $18.18 per Doryx mpc DR 60 mg tablet. In FDA's classes, erythromycin is a macrolide and doxycycline a tetracycline-class drug.
Check it at the source: the erythromycin FDA label on DailyMed (effective August 1, 2024); the doxycycline FDA label on DailyMed (effective July 25, 2025).
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
Highlights of the doxycycline record
Doxycycline (Vibramycin) · label of July 25, 2025
Used for
From the label: indicationsTo reduce the development of drug-resistant bacteria and maintain effectiveness of doxycycline capsules and other antibacterial drugs, doxycycline capsules 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
- December 5, 1967
- Generic labelers
- 83 labelers
- Pharmacy cost
- $0.118 per tablet
Supply and safety
- Shortage
- A presentation being discontinued
- Recalls
- 19
Source: FDA drug labels via openFDA (Erythromycin label of August 1, 2024, Doxycycline label of July 25, 2025); NDC Directory, Drugs@FDA, NADAC, FDA shortages and recalls (October 8, 2026)
How do erythromycin and doxycycline differ on the record?
In FDA's classes, erythromycin is a macrolide and doxycycline a tetracycline-class drug.
Generics: erythromycin since 1964; doxycycline since 1973 (Drugs@FDA).
| Erythromycin | Doxycycline | |
|---|---|---|
| Labeled for | Bacterial infections, Acne | Urinary tract infections, Bacterial infections, Acne |
| Pharmacologic class | Macrolide, Macrolide Antimicrobial | Tetracycline-class Drug |
| How it works (label) | n/a | n/a |
| Half-life (label) | n/a | 1.62 0.95 0.37 0.15 (μg/mL) Average Observed Values Maximum Concentration 3.61 μg/mL (± 0.9 sd) Time of Maximum Concentration 2.60 hr (± 1.10 sd) Elimination Rate Constant 0.049 per hr (± 0.030 sd) Half-Life 16.33 hr (± … |
| Earliest approval on file (Drugs@FDA) | June 25, 1964 | December 5, 1967 |
| First generic approved | June 24, 1964 | June 18, 1973 |
| Generic labelers (NDC) | 38 labelers | 83 labelers |
| Pharmacy cost (NADAC, each one's most listed form; strengths differ) | $1.96 per tablet (Erythromycin 250 mg tablet) | $0.118 per tablet (Doxycycline hyclate 100 mg tablet) |
| 12-month price change | +12% | -2% |
| Boxed warning | No | No |
| Shortage now | No current entry | A presentation being discontinued |
| Recalls recorded | 2 | 19 |
| FAERS reports (a report is not proof of cause; counts follow how widely a medicine is used) | 18,956 | 69,571 |
| 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 erythromycin
- every medicine labeled for the same conditions