Medications · Brain & nerves

Myasthenia Gravis Medicines & Surgery

Myasthenia gravis (MG) doesn't usually stop you having surgery — but it does need careful anesthesia planning. The most important thing you can do is make sure your anesthesia team knows about it as early as possible.

Medically reviewed by Dr. Saurabh Shukla, MBBS, DNB Anesthesiology · Last updated June 2026

Quick answer

Keep taking your myasthenia medicine (pyridostigmine / Mestinon) as normal, usually including the morning of surgery — though your neurologist may fine-tune the timing. The key safety point is that MG makes you much more sensitive to the muscle-relaxant drugs used in anesthesia, and your breathing muscles can be weaker afterward. So your team plans carefully and may watch you for longer. Tell them you have myasthenia well ahead of the day.

Why it matters

MG affects the junction between nerves and muscles. People with MG are often very sensitive to non-depolarizing muscle relaxants (so much smaller doses are used, or they're avoided) and may react unusually to the others. Your anesthesiologist tailors the whole plan around this — which is why early notice matters.

Your breathing and swallowing muscles can be weaker after surgery, so some people need closer monitoring or a short stay in a high-dependency/ICU bed, especially after bigger operations or if your MG isn't well controlled. This is precaution, not alarm.

Pyridostigmine is usually continued. Steroids (like prednisolone) and immune-suppressing medicines (azathioprine, mycophenolate) are generally continued too — and steroids may need an extra 'stress dose' for surgery. Don't stop any of these on your own.

Some other medicines can worsen muscle weakness in MG — certain antibiotics (aminoglycosides, some others), magnesium, and a few heart drugs. Magnesium is the sneaky one: it's in many over-the-counter supplements, antacids and laxatives, and is given by drip during some pregnancy care — so mention any you take. Your team knows the full list; your job is just to make sure 'myasthenia gravis' is on your record and said out loud.

Do not stop without instruction

Don't stop your pyridostigmine, steroids, or immune medicines to 'prepare' for surgery — stopping can worsen your myasthenia. Any change to timing is decided with your neurologist and anesthesiologist together.

What to ask your doctor

  • I have myasthenia gravis — can we discuss the anesthesia plan before the day? (Tell them early.)
  • Should I take my pyridostigmine on the morning of surgery, and at what time?
  • Might I need closer monitoring or an HDU/ICU bed afterward?
  • Do any of my other medicines (or planned drugs) need avoiding because of my MG?

Red flags — call your team

Red flags — call your team

  • Worsening muscle weakness, drooping eyelids, double vision, or — most importantly — difficulty breathing or swallowing before or after surgery. Tell staff at once; this can be a myasthenic crisis.
  • Feeling suddenly much weaker after a change in your pyridostigmine — both too little and too much medicine can cause weakness, so it needs review.

References

  • Myasthenia Gravis Foundation of America — surgery and anaesthesia guidance. myasthenia.org
  • BJA Education — anaesthesia for the patient with myasthenia gravis. bjaed.org
  • OpenAnesthesia — myasthenia gravis and neuromuscular blockade. openanesthesia.org

Frequently asked questions

Do I take my pyridostigmine (Mestinon) on the day of surgery?

Usually yes — pyridostigmine is normally continued, often including the morning dose, though your neurologist may adjust the exact timing. The most important step is telling your anesthesia team you have myasthenia gravis ahead of time so they plan the right anesthetic.

Is anesthesia safe if I have myasthenia gravis?

Yes — people with myasthenia have anesthesia safely, but it needs planning. The team uses much smaller doses of muscle-relaxant drugs (or avoids them), and may monitor your breathing more closely afterward. Giving them early notice is the single most helpful thing you can do.

Why might I need to stay in intensive care after surgery?

Because the breathing muscles can be weaker with myasthenia, some people — especially after major surgery or if their MG isn't well controlled — are watched in a high-dependency or intensive care bed for a short time as a precaution. It's planned ahead, not a sign something went wrong.

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