An erection happens when blood fills the penis. Some blood vessels open wide to let blood flow into the penis. Other blood vessels shrink to keep the blood from leaving the penis. The change in the blood vessels is controlled by nerves.
ED may be caused by:
Blood vessel injury or disease. These can change blood flow.
Harm to nerves that control blood vessels or feeling in the penis.
Stress that change how the nerves work—This is more likely in men with sudden ED.
Hormone problems such as low testosterone or thyroid disease.
Certain medicines such as those that treat high blood pressure, mental health problems, or heart rhythm problems.
Structural problems caused by Peyronie disease, hypospadias, or penile fracture.
The doctor will ask about your symptoms and health past. A physical exam will be done. This will include a genital and rectal exam.
The doctor will ask about the quality of erections. This may include questions about the time of day, how rigid the erection is, and how long it lasts. The doctor may also ask about your mental state, desire, arousal, ejaculation, and orgasms. The answers can help point to the source of the problem.
A nocturnal penile tumescence test will check for erections while you sleep. If you have normal erections during sleep the cause may be psychological. If you have problems with an erection, even while you sleep, the cause may be physical.
Other tests to find a cause may include:
Blood tests—to check for health problems such as diabetes or high cholesterol, or look at testosterone levels
ultrasound—to check blood flow in the penis
Erectile dysfunction. National Institute of Diabetes and Digestive and Kidney Diseases website. Available at:
https://www.niddk.nih.gov/health-information/urologic-diseases/erectile-dysfunction. Accessed July 17, 2019.
Erectile dysfunction. Urology Care Foundation website. Available at: ...(Click grey area to select URL) Accessed July 17, 2019.
Shamloul R, Ghanem H. Erectile dysfunction. Lancet. 2013;381(9861):153-165.
Last reviewed June 2019 by EBSCO Medical Review Board Adrienne Carmack, MD Last Last updated: 10/2/2019