The process of absorbing, digesting, and excreting a medicine or food is called metabolism. The way the body metabolizes a particular medicine affects how often it must be taken. It also determines whether it will interact with other medicines or be affected by conditions such as liver disease.
Keppra is not metabolized by the liver, and does not cause the liver to change how it metabolizes other drugs.
The tablets and the liquid form of Keppra take the same amount of time to be absorbed by the body. This time is a little longer if they are taken with food instead of on an empty stomach, but all the medicine is absorbed either way.
The half-life of Keppra (the amount of time it takes for the blood level to fall by 50%) is generally 6 to 8 hours. Keppra is usually taken two times a day.
The body eliminates Keppra through the kidneys, so people with poor kidney function usually need to take less Keppra and may take it less often, because it stays in their body longer.
How well does Keppra work?
Keppra (levetiracetam) is generally used as add-on (adjunctive) therapy for partial seizures in adults whose seizures are not well controlled by other medications.
In a number of tests in which Keppra was compared to a pill with no active medicine (a placebo), Keppra was significantly more effective than the placebo for people with frequent partial seizures. Between 21% and almost 40% of those who took Keppra as add-on therapy reduced their seizure frequency by half or more, without excessive side effects. The rate of side effects was lower than reported for most other seizure medicines.
No single combination of seizure medicines is perfect for everyone. Sometimes, a series of combinations must be tried before finding what is best for the individual. Because Keppra doesn't interact with other medicines, dosages don't need to be changed when it is given as add-on therapy for seizures or when medicines are taken for other disorders.
At least one study has found that Keppra also may be effective when used alone to treat partial seizures. Keppra was first given as add-on therapy, and the other seizure medicines were gradually stopped if the person's seizure frequency was reduced by at least half. More than half of these people continued to have at least 50% fewer seizures with Keppra alone.
