Mibefradil

Mibefradil

Mibefradil is a calcium channel blocker that was marketed under the brand name Posicor by Roche. It was used in the treatment of hypertension and angina pectoris. However, it was withdrawn from the market in 1998 due to drug interactions.

Pharmacology

Mibefradil is a tetralol derivative and acts as a T-type calcium channel blocker. It selectively inhibits T-type calcium channels over L-type calcium channels, which makes it different from other calcium channel blockers. This selectivity allows it to slow down the heart rate without decreasing the force of contraction of the heart.

Clinical Use

Mibefradil was approved by the Food and Drug Administration (FDA) in 1997 for the treatment of hypertension and chronic stable angina pectoris. It was marketed as a once-daily medication.

Withdrawal from the Market

In 1998, Roche decided to withdraw Mibefradil from the market. This decision was based on reports of severe drug interactions with other medications, including some that could potentially be life-threatening. The drug was found to inhibit the cytochrome P450 enzyme system, which is involved in the metabolism of many other drugs. This inhibition can lead to increased levels of these other drugs in the body, potentially causing toxicity.

See Also

• Calcium channel blocker
• Hypertension
• Angina pectoris
• Food and Drug Administration
• Cytochrome P450