Metoprolol overdose.

We report the first two documented cases of the deliberate metoprolol overdose occurring in the United States, one of which eventually proved fatal. The potentially lethal cardiotoxic effects of this drug are illustrated and correlated with the blood and tissue levels of metoprolol. We emphasize the often sudden and rapid clinical deterioration which excessive ingestion of this drug may produce, and the need for close, careful supervision and monitoring of these patients.