Two medicines, side by side
Cephalexin vs clarithromycin
Cephalexin and clarithromycin are both labeled for bacterial infections. Drugs@FDA records approvals of cephalexin since 1971 and of clarithromycin since 1991. Pharmacies paid $0.120 per cephalexin 500 mg capsule and $0.466 per clarithromycin 500 mg tablet (NADAC, October 7, 2026). In FDA's classes, cephalexin is a cephalosporin antibacterial and clarithromycin a macrolide antimicrobial.
Check it at the source: the cephalexin FDA label on DailyMed (effective December 31, 2020); the clarithromycin FDA label on DailyMed (effective April 9, 2026).
Highlights of the cephalexin record
Cephalexin (Keflex) · label of December 31, 2020
Used for
From the label: indicationsCephalexin is a cephalosporin antibacterial drug indicated for the treatment of the following infections caused by susceptible isolates of designated bacteria: Respiratory tract infection ( 1.1 ) Otitis media ( 1.2 ) Skin and skin structure infections ( 1.3 ) Bone infections ( 1.4 ) Genitourinary tract infections ( 1.5 ) To reduce the development of drug-resistant bacteria and maintain the effectiveness of […]
On the market
- Earliest approval on file
- January 4, 1971
- Generic labelers
- 35 labelers
- Pharmacy cost
- $0.120 per capsule
Supply and safety
- Shortage
- No current entry
- Recalls
- 22
Highlights of the clarithromycin record
Clarithromycin (Biaxin) · label of April 9, 2026
Used for
From the label: indicationsClarithromycin is a macrolide antimicrobial indicated for mild to moderate infections caused by designated, susceptible bacteria in the following: Acute Bacterial Exacerbation of Chronic Bronchitis in Adults (1.1) Acute Maxillary Sinusitis (1.2) Community-Acquired Pneumonia (1.3) Pharyngitis/Tonsillitis (1.4) Uncomplicated Skin and Skin Structure Infections (1.5) Acute Otitis Media in Pediatric Patients (1.6) […]
On the market
- Earliest approval on file
- October 31, 1991
- Generic labelers
- 26 labelers
- Pharmacy cost
- $0.466 per tablet
Supply and safety
- Shortage
- No current entry
- Recalls
- 3
Source: FDA drug labels via openFDA (Cephalexin label of December 31, 2020, Clarithromycin label of April 9, 2026); NDC Directory, Drugs@FDA, NADAC, FDA shortages and recalls (October 8, 2026)
How do cephalexin and clarithromycin differ on the record?
In FDA's classes, cephalexin is a cephalosporin antibacterial and clarithromycin a macrolide antimicrobial.
How each works, in its label's words: Cephalexin, “Cephalexin is a cephalosporin antibacterial drug [see Microbiology ( 12.4 )].”; Clarithromycin, “Clarithromycin is a macrolide antimicrobial drug [see Microbiology (12.4) ].”
Generics: cephalexin since 1976; clarithromycin since 2004 (Drugs@FDA).
| Cephalexin | Clarithromycin | |
|---|---|---|
| Labeled for | Bacterial infections, Urinary tract infections | Bacterial infections, Acid reflux and ulcers |
| Pharmacologic class | Cephalosporin Antibacterial | Macrolide Antimicrobial |
| How it works (label) | Cephalexin is a cephalosporin antibacterial drug [see Microbiology ( 12.4 )]. | Clarithromycin is a macrolide antimicrobial drug [see Microbiology (12.4) ]. |
| Half-life (label) | n/a | The elimination half-life of clarithromycin was about 3 hours to 4 hours with 250 mg administered every 12 hours but increased to 5 hours to 7 hours with 500 mg administered every 8 hours to 12 hours. |
| Earliest approval on file (Drugs@FDA) | January 4, 1971 | October 31, 1991 |
| First generic approved | April 26, 1976 | May 25, 2004 |
| Generic labelers (NDC) | 35 labelers | 26 labelers |
| Pharmacy cost (NADAC, each one's most listed form; strengths differ) | $0.120 per capsule (Cephalexin 500 mg capsule) | $0.466 per tablet (Clarithromycin 500 mg tablet) |
| 12-month price change | -6% | +6% |
| Boxed warning | No | No |
| Shortage now | No current entry | No current entry |
| Recalls recorded | 22 | 3 |
| FAERS reports (a report is not proof of cause; counts follow how widely a medicine is used) | 21,515 | 34,134 |
| 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 cephalexin
- every medicine labeled for the same conditions