Gabapentin is indicated for- Epilepsy Neuropathic pain (e.g. postherpetic neuralgia) and other pain conditions Bipolar disorder Headache syndrome Spasticity in multiple sclerosis and spinal cord diseases Others indication are: Alcohol withdrawal Schizoaffective disorder Post-traumatic stress disorder Agitation and behavioural disturbances associated with dementia Lesch-Nyhan syndrome Essential tremor Restless legs syndrome Brachioradial pruritus Hemichorea/hemiballismus Hot Flashes
Adjunct anti-epileptic drugsa
Gabapentin is an anti-convulsant. It is a structural analog of gamma-amino-butyric-acid (GABA). All pharmacological actions following administration of Gabapentin are due to the activity of parent compound. Gabapentin binds with the alpha-2-delta subunit of voltage gated L-type Calcium channel, and inhibits branched chain amino acid transferase & probably inhibits neurotransmitter release of excitatory amino acid.
Neuropathic pain: 300 mg on day-1, then 300 mg twice on day-2, then 300 mg thrice on day-3, then increase the dose according to response in steps of 300 mg daily to maximum 1800 mg daily in three divided doses. Partial seizure/epilepsy: 300 mg on day-1, then 300 mg twice on day-2, then 300 mg thrice on day-3, then increase the dose according to response in steps of 300 mg daily to maximum 2400 mg daily in three divided doses. In case of children: For 3-12 years: 10 to 15 mg/kg, Incase of titration 25-35 mg/kg daily in 3 divided doses. Maintenance dose is 900 mg daily (body weight 26-36 Kg) or 1.2 gm daily (body weight 37-50 Kg). Gabapentin can be taken orally with or without food.
Antacids may reduce the bioavailability of Gabapentin by up to 20%. Cimetidine may alter its reanal excretion. Gabapentin does not interact with other anti-epileptic drug or with oral contraceptive preparations.
Gabapentin is contraindicated in patients who have known hypersensitivity to the drug.
Generally Gabapentin is well tolerated but a few side effects like fatigue, dizziness , ataxia, weight gain, peripheral edema, dry mouth and somnolence, may occur. Rarely it may cause fulminate hepatic failure, or aplasticanemia.
Pregnancy: Gabapentin is a pregnancy category C drug; it should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Lactation: Gabapentin may be secreted through the breast milk like many other drugs , so it should be used in women who are nursing, only if the benefits clearly outweigh the risks.
Patients should be instructed to take Gabapentin only as prescribed. While using Gabapentin patients should be instructed either not to drive a car or to operate other complex machinery until they have gained sufficient experiences about Gabapentin whether or not it affects their mental and/or motor performance adversely.
Tablets should be stored below 258 C and protected from light & moisture