THERAPEUTICS

Brands

• Gabitril

Generic?

• Yes

Class

• Antiepileptic drug (AED)

Commonly Prescribed for

(FDA approved in bold)

• Adjunctive for partial seizures in adults and children age 12 or older

• Temporal lobe epilepsy (children and adults)

• Panic disorder

How the Drug Works

• Enhances activity of GABA by binding to sites associated with GABA uptake into presynaptic neurons, allowing more GABA to be available to bind to receptors on postsynaptic cells

How Long Until It Works

• Seizures: should decrease by 2 weeks

If It Works

• Seizures: goal is the remission of seizures. Continue as long as effective and well tolerated. Consider tapering and slowly stopping after 2 years without seizures

If It Doesn't Work

• Increase to highest tolerated dose

• Epilepsy: consider changing to another agent, adding a second agent, using a medical device, or a referral for epilepsy surgery evaluation. When adding a second agent, keep drug interactions in mind

Best Augmenting Combos for Partial Response or Treatment-Resistance

• Epilepsy: titration and combination regimen depends on whether the patients are on an enzyme-inducing drug or not

Tests

• No regular blood tests are recommended

ADVERSE EFFECTS (AEs)

How the Drug Causes AEs

• CNS AEs are probably caused by excess GABA effect

Notable AEs

• Confusion, stuttering, muscle tremor, dizziness, sedation, paresthesias (usually doses > 8mg/day), abdominal pain

• Less commonly, behavioral symptoms such as amnesia, extreme confusion, or seizures or seizure-like symptoms

Life-Threatening or Dangerous AEs

• Can precipitate seizure in some patients (rare)

• Severe rash (rare) including Stevens- Johnson syndrome

• Falls producing accidental injury

Weight Gain

• Common

Sedation

• Common

What to Do About AEs

• Decreasing dose may reduce CNS AEs, especially weakness and sedation

• Titrate more slowly