Ciprofloxacin vs Amoxicillin: side-by-side comparison
Ciprofloxacin (Fluoroquinolone antibiotic) and Amoxicillin (Aminopenicillin antibiotic) belong to different therapeutic classes and are rarely substitutes for each other. The comparison is useful when a single patient is weighing both options for adjacent or overlapping needs.
| Property | Ciprofloxacin | Amoxicillin |
|---|---|---|
| Therapeutic class | Fluoroquinolone antibiotic | Aminopenicillin antibiotic |
| CAS | 85721-33-1 | 26787-78-0 |
| ATC | J01MA02 | J01CA04 |
| Molecular weight | 331.34 g/mol | 365.40 g/mol |
| Brands with this active ingredient | 1 | 2 |
What they share
Ciprofloxacin and Amoxicillin share the common regulatory framework for prescription active ingredients, bioequivalence standards for generics, and pharmacist oversight. Beyond that, points in common are limited.
Key differences
Ciprofloxacin acts by a different mechanism than Amoxicillin, with indications that barely overlap. Comparing the two is useful when a clinician has mentioned both in the same context or the patient wants to understand why one was prescribed instead of the other.
Mechanisms compared
Ciprofloxacin: Ciprofloxacin inhibits bacterial DNA gyrase (topoisomerase II) and topoisomerase IV, enzymes essential for DNA replication, transcription and repair. Amoxicillin: Amoxicillin inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins, which prevents the cross-linking of peptidoglycan layers and triggers bacterial autolysis.
Indications compared
Ciprofloxacin: Ciprofloxacin is approved in adults for the treatment of complicated urinary tract infections, acute pyelonephritis, prostatitis, gastrointestinal infections including travellers' diarrhoea, selected respiratory and skin… Amoxicillin: Amoxicillin is approved in adults and children for the treatment of bacterial infections of the upper and lower respiratory tract, urinary tract, ear, nose and throat, dental infections, skin and soft tissue infections…
Safety profile
Ciprofloxacin: Common adverse effects include gastrointestinal symptoms, headache, dizziness and rash. Amoxicillin: Amoxicillin is generally well tolerated.
Frequently asked questions
Is Ciprofloxacin better than Amoxicillin? ▾
Ciprofloxacin and Amoxicillin are not "better or worse" — they treat different things. The sensible question is which fits your specific need.
Can Ciprofloxacin and Amoxicillin be combined? ▾
Whether they can be combined depends on the indications and the interaction profile of each. If both are in a single prescription, the prescriber has weighed it; in self-medication they should never be combined.
Do they have the same side-effect profile? ▾
No — they belong to different classes and have distinct side-effect profiles. Each has its own prescribing information.
Products with Ciprofloxacin
Products with Amoxicillin
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.