Levetiracetam: Levetiracetam
has been recently (1999) approved by the FDA for use as adjunctive
therapy in the treatment of partial-onset seizures with or without
secondary generalisation. It is recommended in individuals above
the age of 16 years; safety in children has not been established.
Levetiracetam is started as 500mg twice a day and can be increased
to a maximum dose of 1500 mg twice a day. Care has to be taken while
prescribing the drug to individuals with liver and kidney diseases.
Most common side-effects observed with levetiracetam include excessive
sleep (somnolence) and headache.
Oxcarbazepine: Approved
in 2000, oxcarbazepine is recommended for monotherapy as well as
adjunctive therapy in adults, and as adjunctive therapy in children
aged four years or older, with partial seizures with or without
secondary generalisation. Oxcarbazepine is started at 600mg/day
(8-10 mg/kg) divided twice a day with increases of 300 mg/day weekly
to a target dose of 1200mg/day. Common side-effects of oxcarbazepine
include headache, somnolence, fatigue, dizziness, nausea; some individuals
can experience slowing of thought, difficulty with concentration,
speech and language problems and coordination difficulties. Oxcarbazepine
is contraindicated in individuals with hypersensitivity to carbamazepine
or oxcarbazepine; pregnancy and lactation.and should be used cautiously
in elderly and individuals with hyponatremia, kidney or liver dysfunction.
Zonisamide: Zonisamide was approved
by the FDA in 2000 and is recommended as adjunctive therapy in individuals
with partial epilepsy. Zonisamide is started as 100 mg/day and is
increased every two weeks; effective doses range from 100-600 mg/day.
Zonisamide is contra-indicated in individuals with hypersensitivity
to sulfa drugs. Safety of zonisamide in individuals below the
age of 16 years has not been established. The most commonly observed
side-effects with the medication include somnolence, anorexia, dizziness,
headache, nausea and irritability. A recent study reported increased
incidence of renal calculi; some patients also complain of slowness
in thinking, skin rashes and blood dyscrasias.
Gamma Knife Surgery:
Gamma Knife Radiosurgery
offers a non-invasive alternative for patients in whom traditional
brain surgery is not an option. The procedure involves stereotactic
delivery of radiation in the form of beams of gamma radiation programmed
to target the offending lesion. Over time, these lesions slowly
decrease in size and dissolve. There is however a long delay of
approximately 12-36 months for optimal results. Gamma-knife surgery
involves reduced hospitalization, is non-invasive and involves lower
risk of infection and bleeding. In some individuals, there is a
transient increase in seizure frequency after the procedure.
Currently, gamma-knife surgery is being evaluated
in epilepsy associated with:
2004