Phenytoin drug level

Phenytoin is a key drug in managing epilepsy, and accurate dosing is essential for the success of therapy. At IntroLab, we offer accurate and reliable tests for measuring phenytoin levels, supporting your healthcare.

What is phenytoin?

Phenytoin is an antiepileptic drug used to control seizures in patients with epilepsy. It works by slowing down excessive electrical activity in the brain that causes seizures. Precise dosing of phenytoin is crucial as it varies from person to person, and regular testing of phenytoin levels in the blood is necessary.

Important notes on phenytoin therapy

As a patient taking phenytoin, it is important to understand all aspects of this treatment. Below are some additional details that may be significant for your experience with this drug:

• Drug interactions: Phenytoin can interact with numerous other medications, which can affect its effectiveness or cause adverse effects.
• Side effects: Nausea, dizziness, coordination problems, or mental changes. If you experience any of these symptoms, you should consult your doctor immediately.
• Consistency in therapy: Phenytoin should be taken exactly as prescribed. Skipping doses or changing the time of medication can lead to problems, including an increased risk of seizures.
• Pregnancy and breastfeeding: Phenytoin can affect fetal development and can be excreted in breast milk. Women who are pregnant, planning a pregnancy, or breastfeeding should talk to their doctor before starting phenytoin therapy.

When and why is the test done?

The phenytoin test is usually performed when starting phenytoin therapy when the dose is changed, or when the patient shows symptoms of overdose or inefficacy of the drug. The goal is to ensure that the phenytoin level in the blood remains within the therapeutic range—high enough to control seizures but not so high as to cause adverse effects.

Preparation for the test

No special preparation is usually required to test phenytoin levels in the blood. However, you should inform your doctor about all the medications you are currently taking, as some drugs can affect phenytoin levels in the blood. The test is usually done before taking the morning dose of the medication.