Vancomycin is NOT contraindicated in myasthenia gravis
Vancomycin can be safely used in patients with myasthenia gravis, as it is not listed among the medications that worsen neuromuscular transmission. The FDA label for vancomycin lists only hypersensitivity as a contraindication, with no mention of myasthenia gravis 1.
Key Evidence
What the Guidelines Say About MG and Antibiotics
The 2018 ASCO guideline on immune-related adverse events specifically addresses myasthenia gravis management and lists medications to avoid: β-blockers, IV magnesium, fluoroquinolones, aminoglycosides, and macrolides 2. Notably, vancomycin is absent from this list.
Clinical Use in MG Patients
Real-world evidence supports vancomycin's safety in MG:
- A case report documented successful vancomycin treatment in a patient with both myasthenia gravis and diabetes mellitus for a prosthetic joint infection, with no reported MG exacerbation 3
- Multiple infectious disease guidelines recommend vancomycin as standard therapy for various serious infections without restrictions for MG patients 4, 5, 6
Antibiotics to Actually Avoid in MG
The medications that CAN worsen myasthenia gravis include:
- Aminoglycosides (gentamicin, tobramycin) - interfere with neuromuscular transmission
- Fluoroquinolones (ciprofloxacin, levofloxacin) - can exacerbate weakness
- Macrolides (azithromycin, erythromycin) - affect neuromuscular junction
- β-blockers - impair neuromuscular transmission
- IV magnesium - blocks acetylcholine release
Clinical Considerations
When treating infections in MG patients:
- Vancomycin remains a first-line option for MRSA and serious gram-positive infections
- Monitor for standard vancomycin adverse effects (nephrotoxicity, ototoxicity) but not MG exacerbation
- Be vigilant about MG deterioration during any infection, as the infection itself—not vancomycin—can worsen MG 7
- Hospitalization may be necessary during infections due to risk of respiratory insufficiency from MG deterioration 7
The bottom line: Use vancomycin when clinically indicated in MG patients without hesitation, but avoid the specific antibiotic classes listed above.