Cialis is a phosphodiesterase inhibitor. It works by helping to increase blood flow into the penis during sexual stimulation. This helps you to achieve and maintain an erection.
Do NOT use Cialis if:
* you are allergic to any ingredient in Cialis
* you have severe kidney problems and will be taking Cialis daily
* you have severe liver problems or certain hereditary degenerative eye problems (eg, retinitis pigmentosa)
* you have certain heart problems (eg, unstable angina, angina during sexual intercourse, severe heart failure, uncontrolled irregular heartbeat), low blood pressure, or uncontrolled high blood pressure
* you have had a heart attack within the past 90 days or a stroke within the past 6 months
* you are taking nitrates (eg, isosorbide, nitroglycerin) in any form (eg, tablet, capsule, patch, ointment) or nitroprusside
* you have been advised by your doctor to avoid sexual activity because of heart problems
* you use certain recreational drugs called “poppers” (eg, amyl nitrate, butyl nitrate)
Contact your doctor or health care provider right away if any of these...