Studies on improvement of pharmaceutical preparations prescribed in hospitals. V. Nifedipine hollow type suppository

Nifedipine is a calcium antagonist used for the treatment of hypertension and angina pectoris. However, commercial nifedipine preparations are only available in forms suitable for oral administration, e.g. soft capsules and tablets. Therefore, we developed a suppository form in which the drug was incorporated into a hollow type suppository. The suppository preparation was administered to humans for evaluation of the clinical and commercial usefulness. It was as fast-acting as the soft capsule, but the blood concentration of nifedipine immediately after administration was lower than that seen with the soft capsule. It was considered to be superior to the soft capsule and similar to the tablet in terms of its long-acting effect. Thus, the hollow type suppository form of nifedipine should have useful clinical applications.