Pyridostigmine 💊

⚠️ Important: Pyridostigmine increases acetylcholine at the neuromuscular junction. In excess, it can cause a cholinergic crisis (depolarising block), which may mimic worsening myasthenia. Avoid in patients with severe asthma.

📖 About

• Check full details in the BNF here.
• Often useful for patients who are weakest on waking (short-term symptomatic relief).

⚙️ Mode of Action

• Reversible acetylcholinesterase inhibitor → ↑ acetylcholine at neuromuscular junction.
• Less potent than neostigmine but longer duration of action.
• In excess, may worsen weakness (cholinergic crisis).

💊 Dose Range (monitor LFTs)

🔗 Interactions

• See BNF for full details (many possible interactions).

⚠️ Cautions

• Asthma (extreme caution)
• Bradycardia, arrhythmias, recent MI
• Epilepsy, hypotension, parkinsonism
• Peptic ulcer disease, hyperthyroidism

🚫 Contraindications

• Bowel obstruction
• Urinary obstruction

❗ Side Effects

• Excess muscarinic activity: sweating, colic, diarrhoea, salivation, gastric hypersecretion, bradycardia.
• Effects can be reversed with atropine-like drugs.

📚 References

• BNF Online: Pyridostigmine Bromide
• Clinical Pharmacology texts