A Textbook of Clinical Pharmacology and Therapeutics

134 ANTI-EPILEPTICS

• Are there remediable or reversible factors that aggravate
  the epilepsy or precipitate individual attacks?


• Is there a clinically important risk if the patient is left
  untreated?


• What type of epilepsy is present?

The ideal anti-epileptic drug would completely suppress
all clinical evidence of epilepsy, while producing no immedi-
ate or delayed side effects. This ideal does not exist (the British
National Formulary currently lists 23 anti-epileptic drugs),
and the choice of drug depends on the balance between effi-
cacy and toxicity and the type of epilepsy being treated. Table
22.1 summarizes the most common forms of seizure and their
drug treatment.
Control should initially be attempted using a single drug
which is chosen on the basis of the type of epilepsy. The dose is
increased until either the seizures cease or the blood drug con-
centration (see Chapter 8) is in the toxic range and/or signs of
toxicity appear. It should be emphasized that some patients
have epilepsy which is controlled at drug blood concentrations
below the usual therapeutic range, and others do not manifest
toxicity above the therapeutic range. Thus, estimation of drug
plasma concentration is to be regarded as a guide, but not an

Is it true epilepsy?

Yes No

No Yes

No Yes

Yes No

Is it secondary to an

underlying CNS or

generalized abnormality?

Are these reversible or

precipitating factors?

Are seizures frequent

and/or likely to present

risk to patients?

Drug treatment

(see Table 22.1)

No drug treatment

Investigate for other

disorder

• Syncope


• dysrhythmia


• pseudo-epilepsy


• metabolic disturbance
  (e.g. hypoglycaemia)


• drug withdrawal


• other
  Consider underlying
  disorder


• brain tumour


• brain abscess


• stroke


• alcohol withdrawal


• other

Address these:

• flashing lights


• stress


• alcohol/alcohol withdrawal


• drugs

Figure 22.1:Pathway for the management of epilepsy.

Table 22.1:Choice of drug in various forms of seizure

Form of seizure First line Second line

Partial seizures with Valproate Phenytoin

or without secondary Carbamazepine Topiramate

generalized tonic–clonic Lamotrigine Tiagabine

seizures

Generalized seizures

Primary (tonic–clonic) Valproate Clonazepam/

Lamotrigine clobazam

Topiramate

Phenytoin

Absence seizures Ethosuximide Lamotrigine

Valproate Clobazam/

clonazepam

Myoclonic jerks Valproate Lamotrigine

Clonazepam

Other anti-epileptics not listed above may be useful. Refer to National

Institute for Clinical Excellence (NICE) guidelines.