Table 3 Selected anti-epileptic drugs (and alternatives to valproate in the treatment of epilepsy), adapted from Schmidt and Schachter [10]

1st generation

Phenytoin

Sodium channel blocker

Enzyme inducer (hence interaction with other medications), skin hypersensitivity

First line for focal and generalised seizures with focal onset

Ethosuxamide

T-type calcium channel blocker

Gastrointestinal side effects, insomnia, psychosis

First line for absence seizures

2nd generation

Carbamazepine

Sodium channel blocker

Enzyme inducer, skin hypersensitivity

First line for focal and generalised seizures with focal onset

Valproate

GABA potentiation, blocks voltage gated sodium channels, epigenetically inhibits histone deacetylase

GI upset, weight gain, tremor, hair loss with curly regrowth, teratogenicity (see Table 4)

In women: polycystic ovarian syndrome, hyperandrogenism

Rare: fulminant liver failure

First line for focal and generalised seizures, no skin hypersensitivity, no newer drugs have been shown to have higher efficacy

3rd generation

Vigabatrin

GABA potentiation

Visual defects, weight gain, seizure aggravation, encephalopathy

Use in infantile spasms, adjunct in complex partial seizures

Lamotrigine

GABA potentiation, suppresses glutamate release, inhibits serotonin reuptake

Tremor, dizziness, tiredness, loss of co-ordination, menstrual disturbance, dry mouth, sleep problems

First line for focal and generalised seizures, lower efficacy than valproate for absence seizures

Oxcarbazepine

Sodium channel blocker

Enzyme inducer, hyponatraemia, skin hypersensitivity

First line for focal and generalised seizures with focal onset

Gabapentin

Calcium channel blocker

Weight gain, psychosis, seizure aggravation, tiredness, dizziness

Adjunctive use only, used in focal and generalised seizures with focal onset

Levetiracetam

SV2A modulation

Tiredness, dizziness, behavioural problems

First line in focal and generalised seizures with focal onset and myoclonic seizures.

Topiramate

GABA potentiation, glutamate inhibition, sodium/calcium channel blocker

Tiredness, dizziness, skin hypersensitivity, weight loss, teratogenicity

First line for focal and generalised seizures