Presentation and Status in Health Basket
Film Coated Tablets
100 X 500 mg
Sabrilan treatment may only be initiated by a specialist in epiletology, neurology or pediatric neurology. Follow up should be carried out under the supervision of a specialist in epileptology, neurology or paediatric neurology.
Sabrilan is intended for oral administration once or twice daily and may be taken before or after meals. The tablets should be swallowed with half a glass of water.
If there is no clinically significant improvement in epileptic symptoms following wellconducted initial treatment, Sabrilan must not be continued. Sabrilan should gradually be withdrawn under close medical supervision.
Tablets are not suitable for children under the age of 6 years, because of the risk of false passage.
Adults: Maximal efficacy is usually obtained with a daily dose of 2 to 3 g. A starting dose of 1 g daily should be added to the patient’s current anti-epileptic drug regimen. The daily dose must then be increased in 0.5 g increments at weekly intervals depending on clinical response and tolerability. The maximum recommended dose is 3g/ day.
There is no correlation between the plasma concentrations and efficacy. The duration of action of the drug is dependent on the rate of GABA-T resynthesis rather than plasma drug concentrations.
Children: The recommended starting dose in children is 40 mg/kg/day. Recommendations in relation to bodyweight for maintenance treatment are as follows:
10-15 kg: 0.5-1 g/day
15-30 kg: 1-1.5 g/day
30-50 kg: 1.5-3 g/day
> 50 kg: 2-3 g/day
The maximum recommended dose in each of these bodyweight categories must not be exceeded.
Elderly subjects and patients with renal insufficiency: Since vigabatrin is eliminated via the kidney, caution should be exercised when administering the drug to the elderly and more particularly in patients with creatinine clearance less than 60 ml/min. Adjustment of dose or frequency of administration must be
considered. These patients may respond to a low maintenance dose. Patients must be closely monitored for possible, undesirable effects such as sedation or confusion.
Hypersensitivity to vigabatrin or to any of the constituents of the medicinal product. Pregnancy, psychoses, behavioral disturbances.
Should not be initiated as monotherapy. Concentric constriction of the visual field of both eyes which is irreversible even after the discontinuation of vigabatrin. All patients should have ophthalmological consultations with visual field examination before the initiation of treatment. If a visual field constriction is observed during follow-up, consideration should be given to gradual discontinuation of therapy. Should not be used concomitantly with other retinotoxic drugs.
Pediatric use: Perimetry is seldom possible in children less than 9 years of developmental age. The risk of treatment must be very carefully weighed against possible benefit.
It is recommended that patients are closely observed for adverse effects on neurological function. As with other antiepileptic drugs, abrupt withdrawal may lead to rebound seizures. History of psychosis, depression or behavioral problems. Patients with a creatinine clearance of less than 60 ml/min and elderly patients should be closely monitored for undesirable effects such as sedation and confusion.
Special care should be taken by patients driving, operating machinery or performing any hazardous task.
For full details see prescribing information.
Visual field defects, usually after months to years of therapy. Increase in seizure frequency. Excitation and agitation, headache, weight gain, tremor. Dizziness, paresthesia, disturbance of concentration and memory. Agitation, aggression, nervousness, irritability, depression, thought disturbance, paranoid reaction. Nausea, abdominal pain, blurred vision, diplopia, nystagmus.
Uncommon: Ataxia, hypomania, mania, psychosis, and rash.
Rare: Encephalopatic symptoms, suicide attempt, retinal disorder, optic neuritis, and optic atrophy. May increase the amount of amino acids in the urine, possibly leading to a false positive test for certain rare genetic metabolic disorders (e.g., elpha aminoadipic aciduria).
A gradual reduction in the plasma concentrations of phenytoin has been observed. May lead to a decrease in measured plasma activity of alanine aminotransferase (ALT) and to a a lesser extent, aspartate aminotransferase (AST). The magnitude of suppression for ALT varies between 30%-100%.
For full details see prescribing information.
Pregnancy and Lactation
Pregnancy: Vigabatrin should only be used during pregnancy if absolutely necessary. Based on data on a limited number of pregnancies where mothers were exposed to vigabatrin, available from spontaneous reports, abnormal outcomes (spontaneous abortions or congenital abnormalities) have been reported in the offspring of mothers taking vigabatrin. Due to limited available data and concomitant administration of other antiepileptic medication during the reported pregnancies, no definitive conclusion can be drawn regarding a possible teratogenic effect of vigabatrin when taken during pregnancy.
The risk of congenital abnormalities is increased 2 to 3 fold in children whose mothers were treated with an antiepileptic. The most frequently reported defects are cleft lip, cardiovascular and neural tube defects. Polytherapy with antiepileptic drugs may be associated with a higher risk of congenital malformation than monotherapy. If a patient becomes pregnant, treatment should be re-assessed. Sudden interruption of effective antiepileptic treatment may lead to worsening of the mother’s condition which can
be detrimental to the fetus. There is no data on the possibility of a visual field defect occurring in children exposed to vigabatrin in utero.
Women of child bearing potential – contraception: Appropriate advice should be given to all women wishing to become pregnant or of childbearing age. The need for antiepileptic treatment must be re-evaluated when a patient is considering pregnancy.
Fertility: Studies in animals have demonstrated that vigabatrin has reproductive toxicity.
Lactation: Vigabatrin is excreted in breast milk. Breast-feeding is not recommended during vigabatrin treatment.
Symptoms: Vigabatrin overdose has been reported. When provided, doses were most commonly between 7.5 to 30 g: however, overdoses up to 90 g have been reported. Nearly half of the cases involved multiple-drug overdose. The most commonly reported symptoms include drowsiness or comma. Other symptoms were less frequently reported and included dizziness, headache, psychosis, respiratory depressin or apnea, bradycardia, hypotension, agitation, irritability, confusion, behavioural disorders and speech disorders. None of the cases of
overdose were fatal.
Management: There is no specific antidote. The usual symptomatic measures should be employed.
Measures to remove unabsorbed drug should be considered. In an in vitro study, activated charcoal was shown not to significantly absorb vigabtrin. The effectiveness of hemodialysis in the treatment of vigabtrin overdose is unknown. In isolated case reports in renal insufficiency patients receiving therapeutic doses of vigabtrin, hemodialysis reduced plasma vigabtrin concentrations by 40% to 60%.