THERAPEUTICS

Brands

• Sabril

Generic?

• No

Class

• Antiepileptic drug (AED)

Commonly Prescribed for

(FDA approved in bold)

• Refractory complex partial seizures in patients ≥ 10 years of age, as adjunctive therapy in patients who have responded inadequately to several alternative treatments

• Infantile spasms: monotherapy in infants 1 month to 2 years of age

• Panic disorder

• Cocaine or methamphetamine dependence

How the Drug Works

• Inhibits catabolism of GABA by inhibiting GABA transaminase (GABA-T). This increases synaptic levels of GABA but does not act directly on GABA receptors. May decrease levels of excitatory neurotransmitters (glutamate, aspartate, glutamine) in the brain

How Long Until It Works

• Seizures: by 2 weeks

If It Works

• Seizures: goal is the remission of seizures. Continue as long as effective and well tolerated

• Monitor vision every 3–6 months

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

• Often used in combination with other AEDs. Lack of significant drug interactions makes it easier to use than many other AEDs

Tests

• No regular blood tests are recommended

ADVERSE EFFECTS (AEs)

How the Drug Causes AEs

• CNS AEs are probably caused by changes in GABA levels

Notable AEs

• Somnolence, fatigue, weight gain, headache, dizziness, anxiety, depression, ataxia, hyperactivity (children), psychosis (adults), upper respiratory tract infection

Life-Threatening or Dangerous AEs

• Retinal atrophy and visual field defects in about one-third of patients, peaking at 1 year but occurring as soon as a few weeks. Visual field loss may be irreversible

Weight Gain

• Not unusual

Sedation

• Not unusual