Melatonin and epileptic seizures in patients with acute intermittent porphyria.

The objective of this study was to assess melatonin production in patients with acute intermittent porphyria (AIP), with and without known epileptic seizures, as a guide to whether melatonin may have anti-convulsive or pro-convulsive effects in AIP. Melatonin concentration in urine, sampled over eight hours on two consecutive nights, was analysed in eight AIP patients with epileptic seizures and in 14 AIP relatives without epilepsy. The AIP patients with epileptic seizures had a significantly lower urinary excretion of melatonin, compared with their AIP relatives without epilepsy, which may indicate that melatonin has a protective effect on seizures.