Drug Information for CYLERT (pemoline) CS-IV (Abbott Laboratories): CLINICAL PHARMACOLOGY

CYLERT (pemoline) has a pharmacological activity similar to that of other known central nervous system stimulants; however, it has minimal sympathomimetic effects. Although studies indicate that pemoline may act in animals through dopaminergic mechanisms, the exact mechanism and site of action of the drug in man is not known.

There is neither specific evidence which clearly establishes the mechanism whereby CYLERT produces its mental and behavioral effects in children, nor conclusive evidence regarding how these effects relate to the condition of the central nervous system.

Pemoline is rapidly absorbed from the gastrointestinal tract. Approximately 50% is bound to plasma proteins. The serum half-life of pemoline is approximately 12 hours. Peak serum levels of the drug occur within 2 to 4 hours after ingestion of a single dose. Multiple dose studies in adults at several dose levels indicate that steady state is reached in approximately 2 to 3 days. In animals given radiolabeled pemoline, the drug was widely and uniformly distributed throughout the tissues, including the brain.

Pemoline is metabolized by the liver. Metabolites of pemoline include pemoline conjugate, pemoline dione, mandelic acid, and unidentified polar compounds. CYLERT is excreted primarily by the kidneys with approximately 50% excreted unchanged and only minor fractions present as metabolites.

CYLERT (pemoline) has a gradual onset of action. Using the recommended schedule of dosage titration, significant clinical benefit may not be evident until the third or fourth week of drug administration.