To understand more about the possible causes of erectile dysfunction (ED) it is useful to understand how erections occur.
Erections
When you become sexually aroused, your brain sends signals to the nerves in your penis. The nerves increase the blood flow to your penis, causing the tissue to expand and harden. Therefore, anything that interferes with your nervous system or your blood circulation could lead to ED.
Anything that affects your libido (level of sexual desire) can also cause ED because a reduced libido makes it more difficult for your brain to trigger an erection. Psychological (mental) factors, such as depression, can reduce your libido, as can changes in your hormone levels (chemicals that are produced by the body).
Physical causes
There are four main types of health conditions that can cause physical problems resulting in ED. These are:
- vasculogenic - conditions that affect the flow of blood to your penis
- neurogenic - conditions that affect your nervous system, which is made up of your brain, nerves and spinal cord
- hormonal - conditions that affect your hormone levels
- anatomical - conditions that affect the physical structure of your penis
Vasculogenic conditions
Examples of vasuclogenic conditions that can cause ED include:
- cardiovascular disease - a disease of the heart or blood vessels, such as atherosclerosis (hardening of the arteries)
- high blood pressure (hypertension)
- diabetes - a condition that is caused by too much glucose (sugar) in the blood. This can affect both the blood supply and the nerve endings in your penis, so it is also a neurogenic condition
ED is strongly associated with cardiovascular disease. For this reason, it may be one of the first causes that your GP considers when making your diagnosis and planning your treatment.
Neurogenic conditions
Examples of neurogenic conditions that can cause ED include:
- multiple sclerosis - a condition that affects the body's actions and activities, such as movement and balance
- Parkinson’s disease - a condition that affects the way that the brain coordinates body movements, including walking, talking and writing
- a spinal injury or disorder
- tumours (growths)
- a stroke - a serious medical condition that occurs when the blood supply to the brain is interrupted
Hormonal conditions
Examples of hormonal conditions that can cause ED include:
- hypogonadism - a condition that affects the production of the male sex hormone, testosterone, causing abnormally low levels
- an overactive thyroid gland (hyperthyroidism) - where too much thyroid hormone is produced
- an underactive thyroid gland (hypothyroidism) - where not enough thyroid hormone is produced
- Cushing's syndrome - a condition that affects the production of a hormone called cortisol
Anatomical conditions
Examples of anatomical conditions that can cause ED include:
- Peyronie's disease - a condition that affects the tissue of the penis
- hypospadias - a condition that causes the urethra (the tube that carries urine from the bladder to the tip of the penis) to develop abnormally on the underside of the penis
Medicinal causes
In some men, certain medicines can cause ED, including:
- diuretics - medicines that increase the production of urine and are often used to treat high blood pressure (hypertension), heart failure and kidney disease
- antihypertensives - medicines, such as beta-blockers, that are used to treat high blood pressure
- fibrates - medicines that are used to lower cholesterol levels
- antipsychotics - medicines that are used to treat some mental health conditions, such as schizophrenia
- antidepressants - medicines that are used to treat depression and some types of pain
- corticosteroids - medication that contains steroids, which are a type of hormone
- H2-antagonists - medicines that are used to treat stomach ulcers
- anticonvulsants - medicines that are used to treat epilepsy
- antihistamines - medicines that are used to treat allergic health conditions, such as hay fever
- anti-androgens - medication that suppresses androgens (male sex hormones)
- cytotoxics - medication used in chemotherapy to prevent cancer cells from dividing and growing
Speak to your GP if you are concerned that a prescribed medication is causing ED. An alternative medication may be available. However, it is important never to stop taking a prescribed medication unless you are advised to do so by your GP or another qualified healthcare professional who is responsible for your care.
Psychological causes
Possible psychological causes of ED include:
- depression - feelings of extreme sadness that last for a long time
- anxiety - a feeling of unease, such as worry or fear
ED can often have both physical and psychological causes. For example, if you have diabetes, it may be difficult for you to get an erection, which may cause you to become anxious about the situation. The combination of diabetes and anxiety may lead to an episode of ED.
There are a number of emotional issues that may also affect your physical ability to get or maintain an erection. These include:
- relationship problems, such as being unable to talk openly about any problems that you have
- lack of sexual knowledge
- past sexual problems
- past sexual abuse
- being in a new relationship
Other causes
Other possible causes of ED include:
- excessive alcohol intake
- tiredness
- using illegal drugs, such as cannabis, heroin or cocaine
