Symptoms of erection problems (erectile dysfunction) include being unable to:

• Have an erection at any time, either with masturbation or with a sex partner.
• Maintain an erection firm enough for sexual intercourse.
• Maintain an erection long enough to complete sexual intercourse.

Even with an erection problem, a man may still have sexual desire and be able to have an orgasm and to ejaculate.

When a man becomes aroused, his brain sends nerve impulses that increase blood flow to his penis. The blood fills the spongy chambers (corpora cavernosa) in the penis, causing it to expand and become rigid. The veins that would normally drain blood from the penis constrict, trapping the blood inside and maintaining the erection.

After ejaculation or when the man is no longer sexually aroused, the arteries narrow, the veins expand, and the blood drains out of the penis. The penis returns to its normal size and is no longer rigid.