What is the therapeutic range for Phenytoin (Dilantin) levels in mcg/mL?

The therapeutic range for Phenytoin (Dilantin) is 10-20 mcg/mL. This range is crucial to achieving the desired anticonvulsant effect while minimizing toxicity. Levels below 10 mcg/mL may not adequately control seizures, potentially leading to breakthrough seizures, while levels above 20 mcg/mL can increase the risk of side effects and toxicity.

Understanding this range is essential in clinical practice to guide therapeutic drug monitoring and ensure patient safety. Phenytoin's pharmacokinetics can be complex, as it exhibits zero-order kinetics at higher doses, making proper dosing and monitoring even more critical. This information helps healthcare providers maintain efficacy in seizure control while safeguarding against the adverse effects associated with elevated levels.