Evaluation of the method for nifedipine administration for a rapid onset of clinical effect: A clinical study in normal volunteers

Nifedipine is frequently used for patients who require an immediate reducti on of blood pressure elevated temporarily by various administration techniq ues including sublingual route without administrating intravenous infusion of vasodilator. A cross-over clinical study was conducted to investigate th e optimal administration metho of nifedipine for rapid management of hypert ension. Four method of administering 10 mg nifedipine (the capsule was bitt en and swallowed, sublingually with a hole in it or the contents administer ed orally or intranasally with a syringe) were evaluated with regarded effi cacy, safety, and usefulness in 6 normal volunteers. Systolic and diastolic blood pressures were correlated with the nifedipine serum concentration in each method. Nifedipine pharmacokinetic parameters differed among the 4 ad ministration methods. Nifedipine was absorbed rapidly by not only intestina l mucosa but also the nasal or oral mucosa. The pharmacological effect of i ntranasal or sublingual administration was superior. However, mint oil whic h is present in nifedipine capsules stimulates nasal mucosa when administer ed intranasally. For clinical usage, nifedipine capsules in which a hole is made with a needle, administered sublingually, can be effectively and safe ly used for rapid management of systemic hypertension.