Basic Neuroscience · Neuropharmacology
Drugs to Avoid in Myasthenia
Medications that can worsen myasthenia gravis, grouped by class and drug family. Individual drug names are listed (rather than drug classes) so the page can be printed and handed to the patient as a reference. Verify before prescribing.
| Category | Medications to avoid — grouped by drug family |
|---|---|
| Antibiotics |
Fluoroquinolones: Ciprofloxacin, Levofloxacin, Ofloxacin, Moxifloxacin, Gemifloxacin, Delafloxacin Macrolides: Erythromycin, Azithromycin, Clarithromycin Ketolide: Telithromycin (contraindicated — boxed warning) Aminoglycosides: Gentamicin, Tobramycin, Amikacin, Kanamycin, Neomycin, Streptomycin Polymyxins: Colistin (colistimethate), Polymyxin B Lincosamide: Clindamycin (low evidence) Penicillins: Ampicillin, Amoxicillin, Penicillin G (rare/relative) Carbapenem: Imipenem |
| Immune checkpoint inhibitors |
PD-1: Pembrolizumab, Nivolumab, Cemiplimab, Dostarlimab, Retifanlimab, Tislelizumab, Toripalimab PD-L1: Atezolizumab, Durvalumab, Avelumab CTLA-4: Ipilimumab, Tremelimumab LAG-3: Relatlimab Can trigger or unmask MG — often severe/fulminant; may overlap with myositis & myocarditis |
| Heart medications |
Class Ia antiarrhythmics: Quinidine, Procainamide, Disopyramide Beta-blockers: Atenolol, Metoprolol, Propranolol, Nadolol, Labetalol, Esmolol, Carvedilol, Bisoprolol, Nebivolol, Sotalol, Pindolol, Acebutolol Calcium-channel blockers: Amlodipine, Nifedipine, Felodipine, Verapamil, Diltiazem Statins: all statins |
| Anesthesia |
Depolarizing NMB: Succinylcholine Nondepolarizing NMBs: Rocuronium, Vecuronium, Pancuronium, Atracurium, Cisatracurium (marked sensitivity — use reduced doses) Inhaled anesthetics: Sevoflurane, Desflurane, Isoflurane |
| Brain / Nerve |
Mood stabilizer: Lithium Anticonvulsants: Phenytoin, Gabapentin, Carbamazepine (reported) Neurotoxin: Botulinum toxin Muscle relaxant: Methocarbamol |
| Rheumatology |
Chelator (DMARD): D-Penicillamine Antimalarials: Hydroxychloroquine, Chloroquine, Quinine (contraindicated) |
| Others |
Ophthalmic β-blockers: Timolol, Betaxolol, Levobunolol, Carteolol (eye drops) Corticosteroids: transient worsening at initiation Contrast: Iodinated contrast Electrolyte: Magnesium (IV / high-dose) Immunomodulators: Interferon-alpha & -beta |
Most listed drugs are relative cautions rather than absolute contraindications — risk is dose-dependent and many can be used with monitoring if needed. Highest-risk / avoid where possible: telithromycin (contraindicated), aminoglycosides, fluoroquinolones, IV magnesium, D-penicillamine, and immune checkpoint inhibitors. Corticosteroids are a mainstay of MG treatment but can cause transient worsening at initiation.
Neuro.Wiki by Ahmed Koriesh, MD — Educational only, not a substitute for clinical judgement