Health Library

The Health Library is a collection of health and wellness resources created for learning and accessibility. Select a topic below for related health information or search for a topic in the search bar for more information on other medical conditions.

Spanish Translation

Blood supply to the penis during an erection

Side view of flaccid penis and erect penis, showing changes in major blood vessels and corpus cavernosa 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 swelling blocks the veins, which traps the blood and maintains the erection.

An erection goes away when the normal blood flow to the penis is restored. The swelling goes down, letting the veins drain the extra blood back to the body. The penis returns to its normal size and becomes soft. This can happen after ejaculation or when someone is no longer sexually aroused.

Current as of: April 30, 2024

Author: Ignite Healthwise, LLC Staff
Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

Current as of: April 30, 2024

Author: Ignite Healthwise, LLC Staff

Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.

This information does not replace the advice of a doctor. Ignite Healthwise, LLC, disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Learn how we develop our content.