Viagra is not for use by females. Remove the syringe from the bottle. However, the dose is usually not more than 80 mg 3 times a day. They’re often the first line of treatment for trouble getting or keeping an erection, called erectile dysfunction ED. Please expect up to 4 to 6 weeks for reimbursement. For erectile dysfunction, it’s best to take sildenafil on an empty stomach.If you have these symptoms, stop taking VIAGRA and contact a doctor right away. have or have had heart problems such as a heart attack, irregular heartbeat, angina, chest pain, narrowing of the aortic valve, or heart failure. have had heart surgery within the last 6 months. have pulmonary hypertension. have had a stroke. Examples of Viagra’s more commonly reported side effects include: headache. flushing (temporary warmth, redness, or deepening of skin color) stuffy nose. indigestion (upset stomach) mild vision.  · Below are details about Viagra dosages commonly used to treat erectile dysfunction (ED).. Viagra form. Viagra comes as tablets that you swallow. Viagra strengths. Viagra tablets are available in.