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Pyridostigmine

Generic name: pyridostigmine

Brand names: Mestinon, Mestinon Timespan, Regonol

Last updated November 3, 2026 0 views
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What is pyridostigmine?

Pyridostigmine works on chemicals in the body that help with communication between nerve impulses and muscle movement.

Pyridostigmine is used to treat the symptoms of myasthenia gravis. It is also used for military personnel who have been exposed to nerve gas.

Pyridostigmine may also be used for reasons not mentioned in this medication guide.

This section was rewritten for readability and reviewed for meaning.

How should I take pyridostigmine?

Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.

Take this medicine with food or milk if it upsets your stomach.

Do not crush, chew, or break an extended-release tablet. Swallow it whole.

Measure liquid medicine with the dosing syringe provided, or with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one.

The amount and timing of this medicine is extremely important to the success of your treatment. Carefully follow your doctor's instructions about how much medicine to take and when to take it.

Your doctor may occasionally change your dose to make sure you get the best results. You may be asked to keep a daily record of when you took each dose and how long the effects lasted. This will help your doctor determine if your dose needs to be adjusted.

If you need surgery, tell the surgeon ahead of time that you are using pyridostigmine. You may need to stop using the medicine for a short time.

Store at room temperature away from moisture and heat.

Keep the tablets in their original container, along with the canister of moisture-absorbing preservative that comes with this medicine.

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Warnings

You should not use pyridostigmine if you have a bladder or bowel obstruction.

This section was rewritten for readability and reviewed for meaning.

Before taking this medicine

You should not use pyridostigmine if you are allergic to it, or if you have a bladder or bowel obstruction.

To make sure you can safely take pyridostigmine, tell your doctor if you have any of these other conditions:

  • asthma; or
  • kidney disease.

FDA pregnancy category C. It is not known whether pyridostigmine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using pyridostigmine.

It is not known whether pyridostigmine passes into breast milk or if it could harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

Pyridostigmine is not approved for use by anyone younger than 18 years old.

This section was rewritten for readability and reviewed for meaning.

Pyridostigmine side effects

Get emergency medical help if you notice any of these signs of an allergic reaction: hives; trouble breathing; swelling of your face, lips, tongue, or throat.

Stop using pyridostigmine and call your doctor right away if you experience any of these serious side effects:

  • extreme muscle weakness;
  • loss of movement in any part of your body;
  • weak or shallow breathing;
  • slurred speech, vision problems; or
  • worsening or no improvement in your symptoms of myasthenia gravis.

Common side effects of pyridostigmine may include:

  • stomach pain, nausea, vomiting, diarrhea;
  • muscle cramps, twitching;
  • sweating, increased salivation;
  • cough with mucus;
  • rash; or
  • blurred vision.

This is not a complete list of side effects, and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

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What happens if I miss a dose?

Take the missed dose as soon as you remember. If it is almost time for your next scheduled dose, skip the missed dose. Do not take extra medicine to make up for the missed dose.

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What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include nausea, vomiting, diarrhea, stomach cramps, sweating, blurred vision, drooling, and weak or shallow breathing.

Worsening muscle weakness, or no change in your myasthenia gravis symptoms, may also be signs of overdose.

This medication may cause blurred vision or impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert and able to see clearly.

Drinking alcohol can increase certain side effects of pyridostigmine.

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What other drugs will affect pyridostigmine?

Other drugs may interact with pyridostigmine, including prescription and over-the-counter medicines, vitamins, and herbal products. Inform each of your health care providers about all medicines you are currently using and any medicine you begin or stop using.

This section was rewritten for readability and reviewed for meaning.

Common questions about pyridostigmine

Can Mestinon be used to treat Postural Tachycardia Syndrome (POTS)?
Mestinon (pyridostigmine) has been used to treat postural tachycardia syndrome (POTS) and may improve symptoms such as a fast heart rate (tachycardia) and symptom burden (Raj et al., 2005). However, research that investigated the addition of Mestinon to standard beta-blocker treatment (propranolol or bisoprolol) found no additional advantage with the addition of Mestinon and suggested beta-blocker therapy alone to be the preferred option (Moon et al., 2018) Continue reading
How does Mestinon help with myasthenia gravis?
Mestinon is a prescription medicine that can help relieve symptoms of myasthenia gravis (MG) such muscle weakness, double vision, blurred vision, drooping eyelids, loss of facial expressions, and difficulties with talking, chewing food, swallowing and breathing. There is no cure for MG, but treatments can help with symptoms. Continue reading
Can I stop taking Mestinon (pyridostigmine)?
Mestinon is a common treatment for myasthenia gravis but 25% of all patients who take it discontinue it because of side effects, and many discontinue it because it does not make any difference to their symptoms. Because it is short-acting, it could theoretically be stopped without tapering it, but you should always talk to your doctor about stopping it before you do so. Continue reading
What's the mechanism for Mestinon (pyridostigmine)?
Mestinon (pyridostigmine) works by blocking an enzyme called acetylcholinesterase. This enzyme normally breaks down acetylcholine, a natural chemical that carries signals from your nerves to your muscles. By slowing that breakdown, Mestinon lets acetylcholine build up where nerves meet muscles, so the signal is stronger and muscles contract better. Continue reading
Is Mestinon an Immunosuppressant?
Mestinon is not an immunosuppressant it is an anticholinesterase inhibitor that slows the breakdown of acetylcholine in the space between nerves and muscles. This helps improve muscle strength by making the signal between nerves and muscles stronger. Mestinon does not affect your immune system, but it is used for autoimmune conditions, such as myasthenia gravis, a neuromuscular disease. It may be also be used off-label to treat postural orthostatic tachycardia syndrome (POTS). Continue reading

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Before you take this medicine: the information on this page is general and may not cover your personal circumstances. Read the label supplied with your medicine and ask a pharmacist or doctor if you are unsure, especially if you are pregnant, breastfeeding, taking other medicines or managing a long-term condition.
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Content is provided for education and is not medical advice. See our medical disclaimer.