Felbamate

Oral
Monotherapy or adjunct in refractory partial seizures with or without secondary generalisation

Reduce initial and maintenance doses by 50%.

Contraindicated.

History of blood disorders. Active liver disease or history of hepatic impairment.

Avoid abrupt withdrawal. Renal impairment. Childn. Pregnancy and lactation.

Nervous: Headache, dizziness, anorexia, insomnia, somnolence, anxiety.
GI: Nausea, vomiting, dyspepsia, constipation or diarrhoea.
Resp: Upper resp tract infection, rhinitis.
Hepatic: Increased SGPT.
Genitourinary: UTI, intramenstrual bleeding.
Ophthalmologic: Diplopia.
Otic: Otitis media.
Dermatologic: Photosensitivity, acne, rash, facial oedema.
Others: Fatigue, decreased wt, hypophosphataemia.
Potentially Fatal: Acute hepatic failure, aplastic anaemia.

PO: C

Avoid exposure to UV radiation.

Perform CBC and LFT prior to and during treatment. Monitor for suicidality (e.g. depression, suicidal thoughts, mood/behavioural changes).

Enhanced metabolism w/ enzyme inducers (e.g. phenobarbital, carbamazepine, phenytoin). Prolonged half-life w/ gabapentin.

Description: Felbamate is a carbamate w/ unknown mechanism of action, but has properties similar to other anticonvulsants. It has weak inhibitory effects on GABA-receptor binding, benzodiazepine receptor binding, and is devoid of activity at the MK-801 receptor binding site of the NMDA receptor-ionophore complex.
Pharmacokinetics:
Absorption: Well absorbed from the GI tract. Bioavailability: ≥80%. Time to peak plasma concentration: 1-6 hr.
Distribution: Enters breast milk. Volume of distribution: 0.76 L/kg. Plasma protein binding: Approx 22-25%, mainly to albumin.
Metabolism: Partly metabolised in the liver via hydroxylation and conjugation to inactive metabolites.
Excretion: Mainly via urine (40-50% as unchanged drug, 40% as inactive metabolites); faeces (<5%). Terminal elimination half-life: 16-23 hr.

Source: National Center for Biotechnology Information. PubChem Database. Felbamate, CID=3331, https://pubchem.ncbi.nlm.nih.gov/compound/Felbamate (accessed on Jan. 20, 2020)

Store between 20-25°C.

Anticonvulsants

N03AX10 - felbamate ; Belongs to the class of other antiepileptics.

Anon. Felbamate. Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 20/02/2017.

Buckingham R (ed). Felbamate. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 20/02/2017.

Felbamate Tablet (Amneal Pharmaceuticals LLC). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/. Accessed 20/02/2017.

McEvoy GK, Snow EK, Miller J et al (eds). Felbamate. AHFS Drug Information (AHFS DI) [online]. American Society of Health-System Pharmacists (ASHP). https://www.medicinescomplete.com. Accessed 20/02/2017.