You should not use vardenafil if you are allergic to it, or if you take other medicines to treat pulmonary arterial hypertension, such as riociguat (Adempas).

Vardenafil is not approved for men younger than 18 years old.

Do not take vardenafil if you are also using a nitrate drug for chest pain or heart problems. This includes nitroglycerin, isosorbide dinitrate, and isosorbide mononitrate. Nitrates are also found in some recreational drugs such as amyl nitrate or nitrite (“poppers”). Taking vardenafil with nitrate medicine can cause a sudden and serious decrease in blood pressure.

Tell your doctor if you have ever had:

• heart disease, heart rhythm problems;
• a heart attack, stroke, or congestive heart failure;
• long QT syndrome (in you or a family member);
• high or low blood pressure;
• seizures;
• liver disease, kidney disease (or if you are on dialysis);
• a blood cell disorder such as sickle cell anemia, multiple myeloma, or leukemia;
• a bleeding disorder such as hemophilia;
• a stomach ulcer;
• hearing or vision problems, vision loss;
• an eye disorder such as retinitis pigmentosa (an inherited condition of the eye);
• a physical deformity of the penis (such as Peyronie’s disease); or
• if you have been told you should not have sexual intercourse for health reasons.

Vardenafil can decrease blood flow to the optic nerve of the eye, causing sudden vision loss. This has occurred in a small number of people, most of whom also had heart disease, diabetes, high blood pressure, high cholesterol, or certain pre-existing eye problems, and in those who smoked or were over 50 years old. It is not clear whether vardenafil is the actual cause of vision loss.

Staxyn may contain phenylalanine. Talk to your doctor before using this form of vardenafil if you have phenylketonuria (PKU).

Vardenafil is not for use in women, and the effects of this medicine during pregnancy or in breastfeeding women are unknown.