First Time User? Sign Up Now
First Time User? Enroll now.
Home > Health Library > Blood supply to the penis during an erection
Arteries and veins carry blood to and from the penis. These blood vessels play an important role in erections.
During an erection, the arteries expand to increase blood flow to the penis. The blood fills two tubes of spongy tissue in the penis (corpus cavernosa). This causes them to swell, making the penis larger and stiff, so it angles out from the body. The veins narrow, which traps the blood and maintains the erection.
After the man ejaculates or is no longer sexually aroused, the veins expand and the trapped blood flows back to the body. The penis returns to its normal size and becomes soft (flaccid).
Current as ofMay 28, 2019
Author: Healthwise StaffE. Gregory Thompson, MD - Internal MedicineAdam Husney, MD - Family MedicineChristopher G. Wood, MD, FACS - Urology
Current as of:
May 28, 2019
Medical Review:E. Gregory Thompson, MD - Internal Medicine & Adam Husney, MD - Family Medicine & Christopher G. Wood, MD, FACS - Urology
To learn more about Healthwise, visit Healthwise.org.
© 1995-2019 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
UNC Medical Center
101 Manning Drive
Chapel Hill, NC 27514
UNC Health Care Citrix
UNC Medical Center Intranet
Copyright 2019 UNC Health Care. All rights reserved.