1.
EPILEPSY
Asiya Naaz
Pharm.D

2.
TREATMENT
GENERAL APPROACH
The treatment of choice depends on the type of epilepsy and on drug-specific adverse effects and patient preferences.is a
suggested algorithm for treatment of epilepsy.
• Begin with monotherapy; about 50% to 70% of patients can be maintained on one antiepileptic drug (AED), but all are not
seizure free.
• Up to 60% of patients with epilepsy are noncompliant, and this is the most common reason for treatment failure.
• Drug therapy may not be indicated in patients who have had only one seizure or those whose seizures have minimal impact on
their lives. Patients who have had two or more seizures should generally be started on AEDs.
• Factors favoring successful withdrawal of AEDs include a seizure-free period of 2 to 4 years, complete seizure control within 1
year of onset, an onset of seizures after age 2 years and before age 35 years, and a normal EEG.
• Poor prognostic factors include a history of a high frequency of seizures, repeated episodes of status epilepticus, a
combination of seizure types, and development of abnormal mental functioning. A 2-year, seizure-free period is suggested for
absence and rolandic epilepsy, while a 4-year, seizure-free period is suggested for simple partial, CP, and absence associated
with tonic-clonic seizures.
According to the American Academy of Neurology guidelines, discontinuation of AEDs may be considered if the patient is seizure
free for 2 to 5 years, if there is a single type of partial seizure or primary GTC seizures, if the neurologic examination and IQ are
normal, and if the EEG normalized with treatment. AED withdrawal should always be done gradually.

3.
MECHANISM OF ACTION
• The mechanism of action of most AEDs includes effects on ion
channels (sodium and Ca), inhibitory neurotransmission (increasing
CNS GABA),or excitatory neurotransmission (decreasing or
antagonizing glutamate and aspartate).
• AEDs that are effective against GTC and partial seizures probably
work by delaying recovery of sodium channels from activation.
• Drugs that reduce corticothalamic T-type Ca currents are effective
against generalized absence seizures.

4.
Drugs of Choice for Specific Seizure Disorders

5.
THE ROLE OF SERUM CONCENTRATION MONITORING
• Seizure control may occur before the “minimum” of the accepted therapeutic
serum range is reached, and some patients may need serum concentrations
beyond the “maximum.”
• The therapeutic range for AEDs may be different for different seizure types (e.g.,
higher for CP seizures than for GTC seizures).
• Clinicians should determine the optimal serum concentration for each patient.
• Serum concentrations can be useful to document lack of or loss of efficacy, to
establish noncompliance, and to guide therapy in patients with renal and/or
hepatic disease and patients taking multiple drugs, as well as in women who are
pregnant or taking oral contraceptives.