API

Magnesium Valproate (400mg)

Drug classification

Anticonvulsant; specifically, a valproate derivative (magnesium salt of valproic acid).

Dosage form

Film-coated extended-release tablet

API strength per dosage

Dose

Standard dosing of magnesium valproate varies by indication and patient factors. In adults, dosing is individualized and titrated to clinical response and serum valproate levels. Use with caution in hepatic impairment; contraindicated in significant liver dysfunction. Paediatric dosing requires specialist guidance. Dose adjustments may be needed in renal impairment. Always refer to local guidelines and monitor for adverse effects.

Mechanism of action

Magnesium valproate increases brain gamma-aminobutyric acid (GABA) levels by inhibiting GABA transaminase and succinic semialdehyde dehydrogenase, reducing neuronal excitability. It also blocks voltage-gated sodium channels and T-type calcium channels, stabilizing neuronal membranes and suppressing abnormal electrical activity, thereby exerting anticonvulsant effects.

Indications

Epilepsy/SeizuresPrevention of Migraine Bipolar disorder

Side effects

Headache Dizziness Blurred vision Loss of appetite Nausea Vomiting Sleepiness Hair loss Weight gain Double vision Diarrhea Impaired coordination Tremors Weakness Stomach pain Increased appetite

Pregnancy category

Magnesium valproate may cause fetal harm; use in pregnancy only if benefits clearly outweigh risks. Effective contraception and specialist consultation are recommended.

Precautions

Monitor liver function, platelet count, serum ammonia, and pancreatic enzymes; use caution in hepatic impairment, mitochondrial disorders, pregnancy, and elderly; watch for signs of hepatotoxicity, pancreatitis, thrombocytopenia, and CNS depression; avoid abrupt discontinuation; assess for drug interactions and hypersensitivity reactions.

Contraindications

Hypersensitivity to valproate or excipients, hepatic dysfunction, significant hepatic impairment, urea cycle disorders, known mitochondrial disorders, especially POLG mutations, porphyria, pancreatitis, pregnancy for migraine prophylaxis.