warnings
WARNINGS Cardiovascular effects General: Physicians should consider the cardiovascular status of their patients, since there is a degree of cardiac risk associated with sexual activity. In men for whom sexual activity is not recommended because of their underlying cardiovascular status, any treatment for erectile dysfunction, including LEVITRA, generally should not be used. Left Ventricular Outflow Obstruction: Patients with left ventricular outflow obstruction, e.g., aortic stenosis and idiopathic hypertrophic subaortic stenosis, can be sensitive to the action of vasodilators including Type 5 phosphodiesterase inhibitors. Blood Pressure Effects: LEVITRA has systemic vasodilatory properties that resulted in transient decreases in supine blood pressure in healthy volunteers (mean maximum decrease of 7 mmHg systolic and 8 mmHg diastolic) (see CLINICAL PHARMACOLOGY , Pharmacodynamics ). While this normally would be expected to be of little consequence in most patients, prior to prescribing LEVITRA, physicians should carefully consider whether their patients with underlying cardiovascular disease could be affected adversely by such vasodilatory effects. Effect of Co-administration of Potent CYP3A4 Inhibitors Long-term safety information is not available on the concomitant administration of vardenafil with HIV protease inhibitors. Concomitant administration with ritonavir or indinavir substantially increases plasma concentrations of vardenafil. Because ritonavir prolongs LEVITRA elimination half-life (5 to 6-fold), no more than a single 2.5 mg dose of LEVITRA should be taken in a 72-hour period by patients also taking ritonavir. Patients taking indinavir, saquinavir, atazanavir or other potent CYP3A4 inhibitors such as clarithromycin, ketoconazole 400 mg daily, or itraconazole 400 mg daily should not exceed a dose of LEVITRA 2.5 mg once daily. For patients taking ketoconazole 200 mg daily or itraconazole 200 mg daily, a single dose of 5 mg LEVITRA should not be exceeded in a 24-hour period (see PRECAUTIONS , Drug Interactions and DOSAGE AND ADMINISTRATION ). Other Effects There have been rare reports of prolonged erections greater than 4 hours and priapism (painful erections greater than 6 hours in duration) for this class of compounds, including vardenafil. In the event that an erection persists longer than 4 hours, the patient should seek immediate medical assistance. If priapism is not treated immediately, penile tissue damage and permanent loss of potency may result. Patient Subgroups Not Studied in Clinical Trials There are no controlled clinical data on the safety or efficacy of LEVITRA in the following patients; and therefore its use is not recommended until further information is available. unstable angina; hypotension (resting systolic blood pressure of <90 mmHg); uncontrolled hypertension (>170/110 mmHg); recent history of stroke, life-threatening arrhythmia, or myocardial infarction (within the last 6 months); severe cardiac failure severe hepatic impairment (Child-Pugh C) end stage renal disease requiring dialysis known hereditary degenerative retinal disorders, including retinitis pigmentosa