Evaluation of two nitroglycerin dosage forms: a metered spray and a soft gelatin capsule.

Two studies were performed to evaluate two nitroglycerin dosage forms. The dosage forms of main interest were a metered 0.4 mg nitroglycerin spray and a soft gelatin capsule containing 0.8 mg nitroglycerin solution. Each of these two dosage forms was evaluated in a separate study, versus both a placebo and an equivalent sublingual nitroglycerin tablet dose. The studies employed the digital plethysmographic methodology for evaluation of organic nitrate antianginal dosage forms. The results indicated that all the nitroglycerin dose treatments generated significantly greater digital plethysmographic activity versus the placebo. Also, the metered spray and soft gelatin capsule treatments were as effective, or more effective, than the respective sublingual tablet treatment in generating a digital plethysmographic response. Several implications and applications of these results are discussed.