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Also known as: [Often referred to by brand name (see MedlinePlus Drug Information)]
Formal name: Phenobarbital

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At a Glance

Why Get Tested?

To monitor the phenobarbital level in your blood to ensure a therapeutic level while avoiding toxic side effects

When to Get Tested?

At the start of therapy and at a regular intervals during treatment; when someone has signs and symptoms of toxicity or is experiencing seizures

Sample Required?

A blood sample drawn from a vein in your arm

Test Preparation Needed?