Generic
Topiramate
16 brands available in the market
At a glance
Topiramate is used to treat epilepsy (seizures) and to prevent migraines. It is also used in the treatment of Lennox-Gastaut syndrome. It controls seizures by decreasing abnormal and excessive activity of nerve cells in the brain.
Description
Topiramate is a sulfamate-substituted monosaccharide with precise mechanism of action unknown. It may block voltage-dependent sodium channels, augment GABA-A receptor activity, antagonize AMPA/kainate glutamate receptors, and inhibit carbonic anhydrase.
Indications
- Epilepsy/Seizures
- Prevention of migraine
- Lennox-Gastaut syndrome
Therapeutic class
Adjunct anti-epileptic drugs
Pharmacological class
Antiepileptic
Pharmacology
Topiramate stimulates GABA-A receptor activity and reduces glutamate activity at AMPA and kainate receptors. It also blocks voltage-dependent sodium channels. These actions decrease neuronal excitability, preventing seizures and migraines.
Mechanism of action
Decreases neuronal excitability, preventing seizures and migraines.
Dosage
Adult Dose (Oral):
- Epilepsy monotherapy: 25 mg nightly initially; increase by 50 mg/day weekly; up to 200 mg twice daily
- Epilepsy adjunctive therapy: 25-50 mg/day initially; 100-200 mg twice daily
- Migraine prophylaxis: 25 mg nightly for 1 week; titrate to 50 mg twice daily over 4 weeks
- Renal impairment: Halve the dose
Administration
- May be taken with or without food
- Swallow whole; do not chew, crush or break
- Take at the same time each day
Missed dose
If you miss a dose, take it as soon as possible; if almost time for next dose, skip it; do not double the dose.
Side effects
Common Side Effects:
- Abdominal pain
- Diarrhea
- Dizziness
- Fatigue
- Fever
- Loss of appetite
- Memory impairment
- Nausea
- Sleepiness
- Weight loss
Precautions & warnings
- May decrease alertness; do not drive
- Regular monitoring of serum bicarbonate levels required
- Drink plenty of fluids to reduce risk of kidney stones
- Do not stop medication suddenly
- Report sudden mood changes or suicidal thoughts
Contraindications
- Hypersensitivity to any component
Drug interactions
- Antiepileptic drugs (phenytoin, carbamazepine, phenobarbital): decreased topiramate plasma concentration
- Carbonic anhydrase inhibitors (acetazolamide): increased risk of renal stone formation
- CNS depressants and alcohol: increased risk of CNS depression
- Valproic acid: increased risk of hyperammonemia and encephalopathy
- Combined oral contraceptives: increased risk of contraceptive failure
Food interactions
It is unsafe to consume alcohol with Topiramate.
Use in pregnancy
Use in Pregnancy: Unsafe; definite evidence of risk to the developing baby; consult your doctor.
Pregnancy Category: C — always consult a doctor before taking during pregnancy.
Use in lactation
Use in Lactation: Probably unsafe; may pass into breast milk and harm the baby; consult your doctor.
Pediatric use
Safety and efficacy not established in children
Geriatric use
Caution required in elderly patients
Renal / hepatic impairment
Renal Impairment: Moderate to severe: halve the dose; hemodialysis: supplemental dose
Hepatic Impairment: Dose adjustment may be needed
Overdose effects
Symptoms: Severe metabolic acidosis.
Treatment: Gastric lavage, activated charcoal, supportive care; hemodialysis is effective.
Storage conditions
Keep below 30°C, away from light and moisture; keep out of reach of children.