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CEPHALEXIN
Cephalexin is a cephalosporin antibacterial drug.
Cephalexin, a first-generation cephalosporin antibiotic, is marketed by various companies and is indicated for treating a range of bacterial infections. It works by inhibiting bacterial cell wall synthesis. Key approved indications include respiratory tract infections, otitis media, skin and skin structure infections, bone infections, and genitourinary tract infections. Cephalexin is differentiated by its broad-spectrum activity and oral administration, making it a convenient option for outpatient treatment. Despite being a generic drug, it remains significant in primary care settings due to its efficacy and safety profile.
At a glance
| Generic name | CEPHALEXIN |
|---|---|
| Also known as | cefalexin |
| Drug class | First-generation cephalosporin |
| Target | Penicillin-binding proteins (PBPs) |
| Modality | Small molecule |
| Therapeutic area | Immunology |
| Phase | FDA-approved |
| First approval | 1971 |
Mechanism of action
Cephalexin is a first-generation cephalosporin that works by inhibiting the synthesis of the bacterial cell wall. It does this by binding to penicillin-binding proteins (PBPs), which are enzymes responsible for cross-linking peptidoglycan chains in the cell wall. By blocking these enzymes, cephalexin weakens the bacterial cell wall, leading to cell lysis and death. This mechanism makes cephalexin effective against a wide range of Gram-positive and some Gram-negative bacteria.
Approved indications
- Respiratory tract infections
- Otitis media
- Skin and skin structure infections
- Bone infections
- Genitourinary tract infections
Pipeline indications
- Chronic urinary tract infection — Phase 2
- Tuberculosis — Phase 2
- Acute uncomplicated cystitis — Phase 2
Common side effects
- Diarrhea
- Nausea
- Vomiting
- Dyspepsia
- Abdominal pain
- Genital candidiasis
- Vaginitis
- Vaginal discharge
- Dizziness
- Fatigue
- Headache
- Agitation
Drug interactions
- Metformin
- Probenecid
- Laboratory or Diagnostic Testing
Key clinical trials
- The Effect of Losartan on Cephalexin (PHASE1)
- Utility of Single-dose Oral Antibiotic Prophylaxis in Prevention of Surgical Site Infection in Dermatologic Surgery (PHASE4)
- Optimizing the Diagnostic Approach to Cephalosporin Allergy Testing (PHASE2)
- Microbiome and Association With Implant Infections (PHASE2)
- Effects of Treatments on Atopic Dermatitis (PHASE2)
- Gram-Negative Bloodstream Infection Oral Antibiotic Therapy Trial (NA)
- Oral Antimicrobial Treatment vs. Outpatient Parenteral for Infective Endocarditis (PHASE4)
- A Clinical Trial of Extended (High) Treatment Dose Antibiotics in Combination With Methenamine Hippurate Compared to the Standard of Care (Either Prophylactic (Low) Dose Antibiotic Treatment or Methenamine Hippurate) in Females With Chronic Urinary Tract Infection (PHASE2)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| FDA label | Mechanism, indications, dosing, boxed warnings, drug interactions |
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- CEPHALEXIN CI brief — competitive landscape report
- CEPHALEXIN updates RSS · CI watch RSS