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 reduction of blood pressure elevated temporarily by various administration techniques including sublingual route without administrating intravenous infusion of vasodilator. A cross-over clinical study was conducted to investigate the optimal administration method of nifedipine for rapid management of hypertension. Four method of administering 10 mg nifedipine (the capsule was bitten and swallowed, sublingually with a hole in it or the contents administered orally or intranasally with a syringe) were evaluated with regarded efficacy, 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 administration methods. Nifedipine was absorbed rapidly by not only intestinal mucosa but also the nasal or oral mucosa. The pharmacological effect of intranasal or sublingual administration was superior. However, mint oil which is present in nifedipine capsules stimulates nasal mucosa when administered intranasally. For clinical usage, nifedipine capsules in which a hole is made with a needle, administered sublingually, can be effectively and safely used for rapid management of systemic hypertension.