No

Anticonvulsant, Miscellaneous

Adjunctive therapy in adults and children greater than or equal to 12 years of age in the treatment of partial seizures

C

Hypersensitivity to tiagabine or any of its ingredients

Anticonvulsants should not be discontinued abruptly because of the possibility of increasing seizure frequency; tiagabine should be withdrawn gradually to minimize the potential of increased seizure frequency, unless safety concerns require a more rapid withdrawal. Rarely, nonconvulsive status epilepticus has been reported following abrupt discontinuation or dosage reduction.

>10%:

Central nervous system: Dizziness, somnolence

Gastrointestinal: Nausea

Neuromuscular & skeletal: Weakness

1% to 10%:

Central nervous system: Nervousness, difficulty with concentration, insomnia, ataxia, confusion, speech disorder, depression, emotional lability, abnormal gait, hostility

Dermatologic: Rash, pruritus

Gastrointestinal: Diarrhea, vomiting, increased appetite

Neuromuscular & skeletal: Tremor, paresthesia

Respiratory: Pharyngitis, cough

Ocular: Nystagmus

Otic: Hearing impairment

Somnolence, impaired consciousness, agitation, confusion, speech difficulty, hostility, depression, weakness, myoclonus, and seizures may occur. Treatment is supportive.

CYP2D6 and 3A3/4 enzyme substrate

Valproate increased free tiagabine concentrations by 40%

The exact mechanism by which tiagabine exerts antiseizure activity is not definitively known; however, in vitro experiments demonstrate that it enhances the activity of gamma aminobutyric acid (GABA), the major neuroinhibitory transmitter in the nervous system; it is thought that binding to the GABA uptake carrier inhibits the uptake of GABA into presynaptic neurons, allowing an increased amount of GABA to be available to postsynaptic neurons; based on in vitro studies, tiagabine does not inhibit the uptake of dopamine, norepinephrine, serotonin, glutamate, or choline

Absorption: Rapid (within 1 hour); food prolongs absorption

Protein binding: 96%

Half-life: 6.7 hours

Children >12 years and Adults: Oral: Starting dose: 4 mg once daily; the total daily dose may be increased in 4 mg increments beginning the second week of therapy; thereafter, the daily dose may be increased by 4-8 mg/day until clinical response is achieved, up to a maximum of 32 mg/day; the total daily dose at higher levels should be given in divided doses, 2-4 times/day

A reduction in seizure frequency is indicative of therapeutic response to tiagabine in patients with partial seizures. Complete blood counts, renal function tests, liver function tests, and routine blood chemistry should be monitored periodically during therapy.

Maximal plasma level after a 24 mg/dose: 552 ng/mL

No information available to require special precautions

No effects or complications reported

Take exactly as directed (do not increase dose or frequency or discontinue without consulting prescriber). While using this medication, do not use alcohol and other prescription or OTC medications (especially pain medications, sedatives, antihistamines, or hypnotics) without consulting prescriber. Maintain adequate hydration (2-3 L/day of fluids unless instructed to restrict fluid intake). You may experience drowsiness, dizziness, disturbed concentration, or blurred vision (use caution when driving or engaging in tasks requiring alertness until response to drug is known); nausea, vomiting, or loss of appetite (small frequent meals, frequent mouth care, chewing gum, or sucking lozenges may help). Wear identification of epileptic status and medications. Report behavioral or CNS changes; skin rash; muscle cramping, weakness, tremors, changes in gait; vision difficulties; persistent GI distress (cramping, pain, vomiting); chest pain, irregular heartbeat, or palpitations; cough or difficulty breathing; worsening of seizure activity, or loss of seizure control. Pregnancy/breast-feeding precautions: Inform prescriber if you are or intend to be pregnant. Breast-feeding is not recommended.

Tablet: 4 mg, 12 mg, 16 mg, 20 mg

Adkins JC and Noble S, "Tiagabine. A Review of Its Pharmacodynamic and Pharmacokinetic Properties and Therapeutic Potential in the Management of Epilepsy," Drugs, 1998, 55(3):437-60.

Dodrill CB, Arnett JL, Sommerville KW, et al, "Cognitive and Quality of Life Effects of Differing Dosages of Tiagabine in Epilepsy," Neurology, 1997, 48(4):1025-31.

Gustavson LE, Boellner SW, Granneman GR, et al, "A Single-Dose Study to Define Tiagabine Pharmacokinetics in Pediatric Patients With Complex Partial Seizures," Neurology, 1997, 48(4):1032-7.

Kalviainen R, Brodie MJ, Duncan J, et al, "A Double-Blind, Placebo-Controlled Trial of Tiagabine Given Three-Times Daily as Add-On Therapy for Refractory Partial Seizures. Northern European Tiagabine Study Group," Epilepsy Res, 1998, 30(1):31-40.

Leach JP and Brodie MJ, "Tiagabine," Lancet, 1998, 351(9097):203-7.

Patsalos PN and Sander JW, "Newer Antiepileptic Drugs: Towards an Improved Risk-Benefit Ratio," Drug Saf, 1994, 11(1):37-67.

Samara EE, Gustavson LE, El-Shourbagy T, et al, "Population Analysis of the Pharmacokinetics of Tiagabine in Patients With Epilepsy," Epilepsia, 1998, 39(8):868-73.

Uthman BM, Rowan AJ, Ahmann PA, et al, "Tiagabine for Complex Partial Seizues: A Randomized, Add-On, Dose-Response Trial," Arch Neurol, 1998, 55(1):56-62.