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licence for patients aged 12 years and older but as adjunctive therapy from two years.
Vigabatrin has a monotherapy licence for use in the management of children with infantile
spasms (West syndrome) in the UK. Topiramate now has a licence for use as monotherapy in
children aged six years and above. The licence for levetiracetam is currently as monotherapy
for patients aged four years and above; this drug also has a licence as adjunctive therapy for
treating focal seizures from one month of age and myoclonic seizures in adults and adolescents
12 years of age and older with juvenile myoclonic epilepsy (JME). Pregabalin, zonisamide and
lacosamide have licences for use as adjunctive therapy in people aged 18 years and above.
Perampanel has a license for adjunctive therapy of focal seizures over the age of 12 years. Of
these new AEDs, lamotrigine, topiramate and levetiracetam would appear to have the broadest
spectrum of action, being effective against many generalised and focal seizure types, and
relatively free of serious side effects, other than lamotrigine producing an allergic or
idiosyncratic rash, that rarely develops into Stevens-Johnson syndrome7,8. Lamotrigine can be
effective in controlling typical absence seizures9 but not as effective in suppressing myoclonic
seizures. Levetiracetam also has a broad spectrum of action against different seizure types and
its safety profile would appear to be relatively impressive, with hostility/aggression as the only
significant and possibly drug-limiting side effects.

Vigabatrin is also a very effective drug in the treatment of infantile spasms10 to the point where
it is recognised as a drug of first choice,11,12, particularly when the underlying cause is tuberous
sclerosis13-15. Vigabatrin is also useful for focal seizures, with or without secondary
generalisation, and appears to be particularly effective in children who have an underlying
structural lesion such as focal cortical dysplasia or even low-grade tumours. However, the drug
may exacerbate myoclonic and typical absence seizures16-20. The drug also appears to have a
relatively impressive short-term safety profile. Rarely, however, behavioural effects may
occur, which manifest as either agitation or a change in muscle tone and an increased appetite;
these effects are transient and resolve once the dose is reduced or the drug withdrawn.
However, the peripheral visual field constriction reported to occur in up to 40% of adult
patients treated with vigabatrin21 is clearly of concern and, consequently, this drug is now only
rarely (possibly never) prescribed to adults or older children for focal seizures. At the current
time, visual field defects have been reported in children but it is not known whether children
are likely to be at a higher or lower risk of developing a visual field defect and also whether
any visual field constriction is more or less likely to be reversible than in adults. The reported
incidence is 2025% and has been derived from older children treated with this drug for focal
seizures but this figure may be higher or lower because it is often very difficult to accurately
obtain formal visual field assessment (perimetry) in children with a cognitive age of <9 years.

Limited data also suggest the occurrence to be related to dose and duration of treatment22.
The drug should only be prescribed in children after careful consideration of the risk:benefit

ratio.

Efficacy and safety data on the use of gabapentin in children are limited, although it does appear
to be effective in focal seizures23-25. Of all the new AEDs, gabapentin appears to be the least
potent in treating focal seizures in children and the one with the lowest chance of rendering
children seizure free24. In adults the drug is effective in focal seizures with and without
evolution to bilaterally convulsive seizures26,27; there is little information on generalised tonic-
clonic seizures, although it would appear to have no effect (beneficial or detrimental) in typical
absences28. Adverse events appear to be both mild and infrequent with gabapentin, and there
are no known drug interactions. Unfortunately, it often has to be administered three times a
day (which has implications for some school children), and as yet there is only a capsule
formulation that restricts its use in children. A ‘mixed fruit’-flavoured suspension is available
in the US.

Topiramate is effective in focal onset seizures and also in the Lennox-Gastaut syndrome29-33
(tonic and atonic seizures seem to respond best). Topiramate may also be effective as