Table 1 Medications that may exacerbate weakness in myasthenia gravis

D-penicillamine

Curare and related drugs

Selected antibiotics including aminoglycosides (tobramycin, gentamycin, kanamycin, neomycin, streptomycin), macrolides (erythromycin, azithromycin, telithromycin [Ketek^®]), and fluoroquinolones (ciprofloxacin, norfloxacin, ofloxacin, pefloxacin)

Quinine, quinidine or procainamide

Beta-blockers

Calcium channel blockers

Magnesium salts (milk of magnesia, some antacids, tocolytics)

Botulinum toxin