A man's penis becomes erect when one of his senses—sight, sound,
taste, touch, or smell—is stimulated and he becomes aroused. His central
nervous system sends nerve impulses that increase blood flow to his penis. As
blood flows into the penis, the penis gets larger and
harder. The blood vessels that drain blood from the penis are blocked enough so
that blood stays in the penis, maintaining the erection.
For a man to have a normal erection, he needs to have an intact
nervous system that receives external stimulus signals and sends arousal
signals to the penis and an intact system of arteries and veins (vascular
system) that allows blood to flow in and out of the penis.
Most
erection problems are caused by a combination of both
physical and psychological factors.
Physical causes of erection problems
Physical causes of erection problems may include illnesses,
injuries, or complications of surgery (such as removal of the
prostate for cancer) that interfere with nerve
impulses or blood flow to the penis. When the nervous system cannot transmit
arousal signals, or when the blood vessels in the penis cannot fill or stay
filled with blood, a man cannot have an erection.
Physical causes of erection problems include:
- Problems with the blood vessels (vascular
problems).
- Problems with the nerves (neurological problems),
such as with
diabetes,
multiple sclerosis, or after a
stroke.
- Problems with the structure of the
penis or surrounding tissues.
- Medicine side effects, such as from
medicines taken for
high blood pressure or
depression.
- Hormone
problems.
- A zinc deficiency.
- Age, particularly being
older than age 50.
Psychological causes of erection problems
Psychological causes of erection problems include depression,
anxiety, stress, grief, and problems with relationships. They interfere with
the erection process by distracting the man from things that would normally
arouse him or by lessening the effect they normally have on him.
Psychological issues account for about 40% of erection problems.
Erection problems in men younger than 50 are more likely to be caused by
psychological issues. Psychological causes of erection problems include the
following:
- Relationship problems
- A man who loses sexual interest in or
desire for a particular partner may develop erection problems.
- A
man who has been widowed recently may have erection problems.
- Some men may have difficulty having sexual
intercourse with their partner after she has given birth.
Erectile dysfunction
Erectile dysfunction (impotence) refers to a man's inability to
achieve or maintain an erection that is sufficient to have sexual intercourse.
It does not mean lack of sexual interest or desire, and the man may or may not
be able to have orgasms or ejaculate. Erectile dysfunction can occur at any
age. Occasional episodes are considered normal and often do not mean there is a
serious problem. Health professionals prefer the term erectile dysfunction over
impotence.
Erectile dysfunction can also be related to another medical
condition, such as:
- Diabetes.
- Heart
disease.
- High blood pressure
(hypertension).
- Liver or kidney disease.
- Alcohol or
drug abuse or withdrawal.
- Pelvic injury or surgery.
Many medicines can cause erectile dysfunction.
Medicines used for erection problems
Medicines that cause an erection may be used for erectile
dysfunction from physical problems. They also may be used along with
counselling to treat erection problems that have psychological causes. Most men
do not have serious side effects from these medicines. However, if you have an
erection that lasts longer than 4 hours after taking a medicine, call your
health professional immediately.