Medicines & Supplements A to Z > Pyridostigmine


Last updated on 15/07/2021.

Overview   |   Dosage   |    Side Effects   |   Precautions  |   Tips  |   Where To Buy  

GENERIC NAME: Pyridostigmine




DRUG CLASS: Central nervous system agents

SUB CLASS: Acetylcholinesterase inhibitors

USED FOR: Myasthenia gravis

AVAILABLE DOSAGE FORMS: 10 mg, 60 mg (tablets)

What is Pyridostigmine for?

Pyridostigmine belongs to a class of medications called central nervous system agents inhibiting an enzyme acetylcholinesterase to slow down the breakdown of a neurotransmitter acetylcholine. Pyridostigmine is used for treating myasthenia gravis.

How to use it?

Pyridostigmine is only available as immediate-release oral tablets in Hong Kong. They should not be broken, crushed or chewed.

Myasthenia gravis
Adult and elderly
30-120 mg per dose, usually 5-6 doses, up to a total daily dose of 0.3-1.2 g.

Child below 12 years of age
30-360 mg in divided doses. For those who are below 6 years of age, start from 30 mg daily. For those who are 6-12 years of age, start from 60 mg daily.

What are the side effects of Pyridostigmine?

Common side effects of Pyridostigmine include abdominal pain, diarrhoea, dysmenorrhoea, muscle pain, twitching and confusion.

Who should not take Pyridostigmine?

– People allergic to Pyridostigmine, anticholinesterase agents or any component of the formulation.
– Patients with mechanical intestinal or urinary obstruction.

Pharmacist Tips:

– Adjust your eating routine based on when you have good muscle strength.
– Use safety precautions at home like railings.
– Choose the time when you have more energy to do your normal routine or other matters that require much energy.

Common dosing schedule:
Pyridostigmine is usually taken 5-6 times daily.

This schedule is for reference only, adjustments may be made according to individual needs. 

Some common medications Pyridostigmine may interact with:
– Beta-blockers, e.g. Bisoprolol, Metoprolol, Propranolol
– Anticholinergic agents, e.g. Atropine, Benztropine, Benzhexol
– Cholinergic agonists, e.g. Pilocarpine, Donepezil, Parathion
– Corticosteroids, e.g. Hydrocortisone, Dexamethasone, Prednisolone

Pyridostigmine may interact with many other medications. Please notify your doctor or pharmacist if you are taking the above medication, dosage adjustments might be needed.

Where to buy Pyridostigmine in Hong Kong?

In Hong Kong, Pyridostigmine is a prescription only medicine, and requires a prescription from a doctor to be purchased in a pharmacy. It can also be obtained from doctors. To find a pharmacy near you, refer to the list of pharmacies (“Authorized Sellers of Poisons”) from the Hong Kong Department of Health.

For more information about drug names and ingredients, you can visit Hong Kong’s Drug Office at

Need more information?

For detailed information about the use of Pyridostigmine in children, pregnancy and breastfeeding, and for questions about drug interactions, please check with your pharmacist or doctor.

Disclaimer: our goal is to provide you with the most relevant drug information and common dosage for Hong Kong. This information does not constitute medical advice. For specific treatment recommendations and advice, always discuss with your doctor or pharmacist, and follow the instructions included with your specific medicine.