There are 4 generic side effects
- Allergic reactions (rash, pruritus, anaphylaxis)
- Gastrointestinal disturbances (nausea, vomiting, diarrhoea, abdominal pain)
- Superinfection, including
- Thrush (Candida albicans)
- C. difficile-associated diarrhea
- Thrombophlebitis at the infusion site (for IV dosing)
Here are the common side effects associated with each of the listed antibiotic classes:
- Fluoroquinolones (Moxifloxacin, Ciprofloxacin, Norfloxacin):
- Tendonitis and tendon rupture
- QT prolongation
- Photosensitivity
- Central nervous system effects (headache, dizziness, insomnia, and rarely seizures)
- Macrolides (Clarithromycin, Erythromycin, Azithromycin):
- Abnormal liver function tests and hepatotoxicity
- QT prolongation and arrhythmias
- Eosinophilia
- Hearing impairment (especially with higher doses)
- Cephalosporins (Cefuroxime, Cephalexin, Ceftriaxone):
- Alteration in blood clotting (with some cephalosporins)
- Renal toxicity (particularly with higher doses or prolonged use)
- Oral and vaginal candidiasis (thrush)
- Aminoglycosides (Gentamicin, Neomycin):
- Nephrotoxicity
- Ototoxicity (hearing loss, balance disturbance)
- Neuromuscular blockade
- Penicillins (Penicillin, Flucloxacillin, Amoxicillin):
- Interstitial nephritis (rare)
- Tetracyclines (Doxycycline):
- Discoloration of teeth and inhibition of bone growth in children
- Photosensitivity
- Heartburn
- Hepatotoxicity (rare)
- Vestibular disturbances (dizziness, vertigo)
- Glycopeptides (Vancomycin):
- Nephrotoxicity
- Ototoxicity
- “Red man syndrome” (flushing, rash, pruritus, hypotension, and tachycardia, usually related to rapid infusion)
- Lincosamides (Clindamycin):
- Rarely, blood disorders (leukopenia, neutropenia)
- Nitroimidazoles (Metronidazole):
- Metallic taste in mouth
- Disulfiram-like reaction with alcohol (flushing, tachycardia, nausea)
- Dark urine discoloration
- Neurological disturbances (headache, dizziness, peripheral neuropathy with prolonged use)