Safety, tolerability and pharmacokinetics of an intravenous bolus of sildenafil in patients with pulmonary arterial hypertension.

To assess pharmacokinetics and pharmacodynamics of a 10 mg intravenous sildenafil bolus in pulmonary arterial hypertension (PAH) patients stabilized on 20 mg sildenafil orally three times daily. Pharmacokinetic parameters were calculated using noncompartmental analysis. After an acute increase, plasma concentrations stabilized within the range reported previously for a 20 mg oral tablet. At 0.5 h, mean ± SD changes from baseline were -8.4 ± 11.7 mmHg (systolic pressure), -2.6 ± 7.3 mmHg (diastolic pressure) and -3.5 ± 10.4 beats min(-1) (heart rate). There was no symptomatic hypotension. Although further research is warranted, a 10 mg sildenafil intravenous bolus appears to provide similar exposure, tolerability and safety to the 20 mg tablet. © 2011 The Authors. British Journal of Clinical Pharmacology © 2011 The British Pharmacological Society. Show more