Felbamate
Class: Antiepileptic (carbamate derivative)
Indications
- Adjunctive or monotherapy for refractory partial seizures
- Lennox–Gastaut syndrome (severe childhood epilepsy)
- Reserved for patients unresponsive to other antiepileptics due to toxicity risks
Mechanism of Action
- Blocks NMDA receptor (glutamate-mediated excitatory transmission)
- Modulates GABAergic function
- Blocks voltage-gated sodium channels
Dosage
- Adults: Start 1200 mg/day orally in 3–4 divided doses; increase by 600–1200 mg every 1–2 weeks up to 3600 mg/day (max)
- Children: 15 mg/kg/day in 3–4 doses; increase gradually to 30–45 mg/kg/day
Major Side Effects
- Insomnia, headache, dizziness
- GI upset (anorexia, nausea, vomiting)
- Weight loss
- Severe: Aplastic anemia (rare but often fatal)
- Severe: Hepatic failure
Contraindications
- History of aplastic anemia
- History of hepatic dysfunction or liver failure
- Hypersensitivity to felbamate
Compatible Solvent / Administration
- Oral tablets or suspension
- Administer with or without food
Special Precautions
- Requires written informed consent due to risk of aplastic anemia and hepatic failure
- Monitor CBC and liver function tests frequently
- Reserved only for severe refractory epilepsy cases
Key Point: Felbamate is effective in refractory seizures and Lennox–Gastaut syndrome but is rarely used due to life-threatening risks of aplastic anemia and hepatic failure.