MESTINON(pyridostigmine bromide) 60MG Tabs 200`S

Pyridostigmine is a reversible inhibitor of acetylcholinesterase — the enzyme that breaks down acetylcholine (ACh) at neuromuscular junctions. By inhibiting this enzyme, pyridostigmine increases the concentration and duration of ACh at the neuromuscular junction, improving muscle strength in conditions where the signal between nerve and muscle is impaired.

It is used to treat:

•       Myasthenia gravis (MG) — the primary symptomatic treatment for muscle weakness caused by autoimmune destruction of acetylcholine receptors at the neuromuscular junction.

•       Reversal of non-depolarising neuromuscular blockade — in anaesthesia (usually IV neostigmine is used for this purpose; pyridostigmine is the oral formulation for chronic use).

The dose is individualised to each patient's level of muscle weakness. Typical starting dose: 30–60 mg every 4–6 hours. Usual maintenance: 60 mg 3–5 times daily; maximum 1.5 g/day. Take with food or milk to reduce GI upset. Do not crush or chew. The 200-tablet pack supports approximately 3–8 weeks of treatment at typical doses.

Pyridostigmine is contraindicated in: mechanical obstruction of the GI or urinary tract; known hypersensitivity to pyridostigmine or other anticholinesterase agents; and perioperative management in certain settings.

Use with caution in: bronchial asthma (increases secretions/bronchospasm); bradycardia or AV block; recent MI; epilepsy; and pregnancy (neonatal myasthenia possible if mother is on high doses).

•       Aminoglycosides, polymyxins, tetracyclines (in high IV doses): can worsen neuromuscular blockade — avoid in MG.

•       Beta-blockers: additive bradycardia and bronchospasm risk.

•       Corticosteroids (used in MG immunotherapy): can transiently worsen MG at initiation — monitor closely.

•       Atropine / anticholinergic drugs: antagonise pyridostigmine effects — may be used therapeutically to manage side effects.

•       Depolarising neuromuscular blockers (suxamethonium): prolonged neuromuscular blockade when given to patients on pyridostigmine — inform anaesthetist.

Store below 25°C, away from moisture. Original container — exposure to air and humidity degrades the tablets. Keep out of reach of children.

Pyridostigmine improves muscle strength in myasthenia gravis but does not treat the underlying autoimmune cause. Most patients also require immunotherapy (prednisolone, azathioprine, or other agents) to achieve lasting remission.

The relationship between dose and benefit is not linear — too much pyridostigmine is as dangerous as too little. Never exceed the dose prescribed without consulting your neurologist. Learn to recognise the difference between a myasthenic crisis (too weak — need more medicine) and a cholinergic crisis (too much medicine — symptoms include extreme secretions, very small pupils, diarrhoea). Both are emergencies requiring hospitalisation.

Carry a medical alert card or bracelet identifying yourself as having myasthenia gravis, and carry an emergency card listing your neurologist's contact and treatment plan.

The 200-tablet pack of 60 mg tablets supports approximately 3–5 weeks of treatment at typical doses (180–300 mg/day in 3–5 divided doses). Dose titration in MG is highly individualised based on symptom severity, muscle groups affected, and daily activities. Patients often require higher doses during stress, infection, or surgery.

Slow-release pyridostigmine (Mestinon Timespan 180 mg) is available for overnight use to prevent nocturnal worsening. MG patients must carry a list of drugs to avoid — including many antibiotics (aminoglycosides, fluoroquinolones), cardiac drugs, and anaesthetics. Alert all healthcare providers.

What is myasthenia gravis, and how does pyridostigmine help?

MG is an autoimmune condition where antibodies attack the junction between nerves and muscles, causing progressive weakness. Pyridostigmine prevents the enzyme that breaks down acetylcholine (the nerve-muscle signal molecule) from working, so more acetylcholine accumulates at the junction and muscle strength improves.

What if I become very weak and have trouble breathing?

Call emergency services immediately — this is a myasthenic crisis. Go directly to hospital. Tell the ambulance team you have myasthenia gravis.

Why do I have so much saliva and stomach cramps?

These are cholinergic side effects of the medicine — it stimulates all cholinergic pathways, not just at the neuromuscular junction. Taking pyridostigmine with food reduces GI effects. Your neurologist may prescribe an anti-secretory medicine (e.g., propantheline) to manage excessive secretions.

Does pyridostigmine cause any heart effects?

It can slightly slow the heart rate (bradycardia). If you notice an unusually slow pulse, light-headedness, or chest discomfort, inform your neurologist.

I am having surgery — does my anaesthetist need to know about this medicine?

Yes — absolutely. Pyridostigmine significantly alters how anaesthetic muscle relaxants (neuromuscular blockers) work. Your anaesthetist must know you are taking pyridostigmine before any surgery.