Title: Myasthenia: medications to avoid - Armstrong Neurology
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Content: Caution should therefore be exercised. 3. Use the following oral antibiotics with caution: Quinolone antibiotics. There have been a number of cases of acute exacerbation with Ciprofloxacin and Norfloxacin. Caution should also be exercised with others in the family (e.g. Moxifloxacin) as it is thought that quinolones directly affect neuromuscular transmission. Macrolide antibiotics – Erythromycin / Azithromycin
There is one case report of a serious exacerbation with azithromycin requiring mechanical ventilation for 6 days. This patient also had an exacerbation from erythromycin. Tetracyclines (e.g. oral forms doxycycline, minocycline; IV form tigecycline)
Sulfonamides (e.g. Septrin™ Bactrim™)
Ampicillin
There is little evidence of problems with other penicillins.