• Metabolism: Hepatic Half Life: 20-23 hours
• Uses/Sources: For use only in those patients who respond inadequately to alternative treatments and whose epilepsy is so severe that a substantial risk of aplastic anemia and/or liver failure is deemed acceptable in light of the benefits conferred by its use.
• Health Effects: May cause a potentially dangerous rash that may develop into Stevens Johnson syndrome, an extremely rare but potentially fatal skin disease.
• Treatment: General supportive measures should be employed if overdosage occurs. It is not known if felbamate is dialyzable. (L1712)
• Route of Exposure: Oral. >90%

• Carcinogenicity: No indication of carcinogenicity to humans (not listed by IARC).
• Toxicity: LD50: 5000 mg/kg (Oral, Rat) (A308)

The mechanism by which felbamate exerts its anticonvulsant activity is unknown, but in animal test systems designed to detect anticonvulsant activity, felbamate has properties in common with other marketed anticonvulsants. <i>In vitro</i> receptor binding studies suggest that felbamate may be an antagonist at the strychnine-insensitive glycine-recognition site of the N-methyl-D-aspartate (NMDA) receptor-ionophore complex. Antagonism of the NMDA receptor glycine binding site may block the effects of the excitatory amino acids and suppress seizure activity. Animal studies indicate that felbamate may increase the seizure threshold and may decrease seizure spread. It is also indicated that felbamate has weak inhibitory effects on GABA-receptor binding, benzodiazepine receptor binding.