Klonopin (clonazepam) belongs to a class of medications called benzodiazepines, which lower brain activity. As a result, common symptoms include:

• tiredness
• dizziness
• unsteadiness
• impaired attention and memory
• irritability
• hyperactivity (in children)
• drooling (in children)
• depression (usually in adults)
• nausea
• loss of appetite

Scientific studies show that about half of people treated for seizures with Klonopin experience drowsiness and about 30% have problems with coordination. In some cases, these problems diminish with time.

About 25% have behavior problems such as hyperactivity in children. Problems with thinking and behavior are greater with Klonopin than with seizure medicines like Tegretol, Dilantin, and Depakote.

If these problems do not go away within several days, or are really bothersome, call the doctor. Sometimes the doctor can help with these side effects by changing the prescription:

• reducing the overall amount of Klonopin
• changing the amount taken at certain times, such as taking a greater proportion of the Klonopin at bedtime to reduce daytime sleepiness
• prescribing smaller doses, to be taken more often

No one should stop taking Klonopin or change the amount they take or when they take it without their doctor's guidance.

People who have just started taking Klonopin (or who have just started taking a larger amount) should be careful during activities that might be dangerous, until they know whether they are having any side effects.

Reviewed February 2004 by Steven C. Schachter, MD, epilepsy.com Editorial Board.