Precautions

Drug information provided by: IBM Micromedex

It is important that your doctor check your progress at regular visits to make sure that this medicine is working properly and to check for unwanted effects.

Do not take avanafil (Stendra®), riociguat (Adempas®), sildenafil (Viagra®), tadalafil (Cialis®), or vardenafil (Levitra®) while you are using this medicine. Using these medicines together may cause blurred vision, severe dizziness, lightheadedness, or fainting. If you are taking these medicines and you experience an angina attack, you must go to the hospital right away.

Dizziness, lightheadedness, or faintness may occur, especially when you get up quickly from a lying or sitting position. Getting up slowly may help.

Dizziness, lightheadedness, or fainting is also more likely to occur if you drink alcohol, stand for long periods of time, exercise, or if the weather is hot. While you are taking this medicine, be careful to limit the amount of alcohol you drink. Also, use extra care during exercise or hot weather or if you must stand for long periods of time.

Call your doctor right away if you have chest pain, fever, joint pain, or unusual tiredness or weakness. These may be symptoms of an autoimmune disease called systemic lupus erythematosus.

This medicine may cause nerve problems. Call your doctor right away if you have burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings.