Side effects

Side effects of oral ED medicines are often mild. Common ones include:

• Flushing of the skin.
• Headache.
• Upset stomach.
• Visual changes, such as blue tinge to vision, sensitivity to light or blurred sight.
• Stuffy or runny nose.
• Back pain.
• Dizzy feeling.

Rarely, more-serious side effects can happen, including:

• Hearing loss or vision loss. Some people have suddenly lost some of their hearing or vision after taking one of these medicines. But it isn't clear whether these side effects were caused by the medicine or by health conditions that the people already had. Get medical care right away if you take oral ED medicine and have sudden loss of hearing or vision.
• An erection that doesn't go away on its own. Called priapism, this rare condition can be painful. You need to get treatment for it as soon as possible to help prevent damage to your penis. If you have an erection that lasts more than four hours, call your care team right away.