vigabatrin at a glance
Medicine class
Antiseizure treatment; irreversible GABA-transaminase inhibitor
Licensed roles
Infantile spasms and resistant focal epilepsy
Specialist oversight
Treatment is started and followed by an epilepsy, neurology or paediatric neurology specialist
Important monitoring
Regular specialist eye assessment is required because peripheral vision loss may occur without noticeable symptoms
Food
May be taken before or after food
What is vigabatrin used for?
Licensed uses represented by the selected products are:
Used alone for infantile spasms, also called West syndrome.
Used with other antiseizure treatments for resistant focal epilepsy, with or without spread to both sides of the brain, when appropriate combinations have been inadequate or not tolerated.
Kigabeq soluble tablets are specifically licensed for infants and children from one month to under seven years within these indications.
How does vigabatrin work?
Vigabatrin permanently blocks GABA-transaminase, the enzyme that breaks down GABA. This raises levels of GABA, an inhibitory brain messenger, helping reduce excessive electrical activity that causes seizures. Its effect depends more on replacement of the blocked enzyme than on blood concentration.
vigabatrin preparations and strengths
Oral solution
Route: Oral
Strengths: 100 mg/mL, 500 mg
Tablet
Route: Oral
Strengths: 500 mg
How to take vigabatrin
Take vigabatrin exactly as prescribed and do not alter or stop it independently. It may be taken with or without food.
Measure ready-made oral solution with the supplied oral syringe. The measured liquid may be mixed with cold water, juice or milk as directed; wash the syringe with water afterwards.
Dissolve Kigabeq soluble tablets only in water and give the full mixture immediately. Rinse the glass with a little water and give that as well.
Kigabeq may be given through a suitable gastric tube when directed by the specialist.
The score on Sabril film-coated tablets is for easier swallowing, not for preparing equal portions.
vigabatrin side effects
Common or expected effects
- Sleepiness, tiredness or reduced concentration
- Headache, dizziness or tremor
- Agitation or excitation, particularly in children
- Mood or behavioural changes, including irritability or depression
- Nausea, vomiting or abdominal discomfort
- Weight gain
- Blurred or double vision
Get urgent medical advice
- Peripheral visual-field loss, which may be severe, unnoticed and irreversible
- Worsening seizures, new seizure types or status epilepticus
- Marked sedation, stupor, confusion or encephalopathy
- Suicidal thoughts or behaviour, psychosis or severe behavioural change
- Angioedema, including swelling of the face or throat
- New movement disorders, especially in infants treated for infantile spasms
vigabatrin in pregnancy
Information about vigabatrin in pregnancy remains limited, so harm cannot be confirmed or excluded. It may be continued or used when a specialist considers seizure-control benefits to outweigh possible risks. Anyone planning a pregnancy or becoming pregnant should obtain prompt specialist review and should not stop vigabatrin suddenly.
vigabatrin while breastfeeding
Vigabatrin passes into breast milk, but evidence about effects in breastfed infants is insufficient. The prescriber should weigh the importance of treatment against the benefits of breastfeeding and discuss options with the parent.
vigabatrin interactions
Vigabatrin has relatively few metabolic interactions, but clinically relevant combinations include:
Phenytoin
Vigabatrin can lower phenytoin blood concentrations; clinical response and levels may need review.
Clonazepam
The combination may increase sedation, so the need for concurrent use should be assessed.
Common questions about vigabatrin
Answers are fully visible for fast scanning and source review.
Why are eye tests needed?
Vigabatrin can narrow peripheral vision, sometimes severely, and many affected people notice no early symptoms. Specialist testing is needed before and throughout treatment.
Can vision loss be permanent?
Yes. Vigabatrin-associated visual-field loss is usually irreversible, even after treatment is stopped.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.