Dantrolene 💊

📖 About

Always check the BNF link here for up-to-date prescribing information.

• 💊 Alternative to baclofen for reducing muscle tone and spasticity.
• 🚨 Specific role in treating malignant hyperthermia (MH) and neuroleptic malignant syndrome (NMS).

⚙️ Mechanism of Action

• Acts directly on skeletal muscle.
• Blocks calcium release from the sarcoplasmic reticulum.
• Impairs excitation–contraction coupling → muscle relaxation.

🎯 Indications

• Spasticity in neurological conditions (alternative when baclofen poorly tolerated or ineffective).
• Malignant hyperthermia (anaesthetic emergency) 🛑.
• Neuroleptic malignant syndrome (antipsychotic emergency) ⚡.

💊 Dantrolene – Dosing

🔗 Interactions

• Concurrent oestrogens may increase risk of hepatotoxicity.
• Use caution with other hepatotoxic drugs.

⛔ Contraindications

• Active or previous liver disease (risk of hepatotoxicity).
• Pregnancy (safety not established).

⚠️ Side Effects

• Drowsiness, dizziness, weakness, vertigo 😵.
• GI upset: nausea, diarrhoea.
• Hepatotoxicity (dose-related, especially at >400 mg/day or with long-term use) ⚠️.
• Photosensitivity reactions (rare).

📚 References

• BNF – Dantrolene
• Oxford Handbook of Clinical Medicine.
• Anaesthesia textbooks – malignant hyperthermia management.