Erectile Process
To understand what causes erectile dysfunction or ED, it is important to first review how an erection occurs. For a man to have an erection, a complex process takes place within the body.
An erection involves the central nervous system, the peripheral nervous system, psychological and stress-related factors, local factors with the erection bodies or the penis itself, as well as hormonal and vascular (blood flow or circulation) components. The penile portion of the process leading to an erection represents only a single component of a very complicated and complex process.
Erections occur in response to touch, smell, and auditory and visual stimuli that trigger pathways in the brain. Information travels from the brain to the nerve centers at the base of the spine, where primary nerve fibers connect to the penis and regulate blood flow during erections and afterward.
Sexual stimulation causes the release of chemicals from the nerve endings in the penis that trigger a series of events that ultimately cause muscle relaxation in the erection bodies of the penis. The smooth muscle in the erection bodies controls the flow of blood into the penis. When the smooth muscle relaxes, the blood flow dramatically increases, and the erection bodies become full and rigid, resulting in an erection. Venous drainage channels are compressed and close off as the erection bodies enlarge.
Detumescence (the process by which the penis becomes flaccid) results when muscle-relaxing chemicals are no longer released.
If one or more of the above physical and/or psychological processes is disrupted, erectile dysfunction can result. Erectile dysfunction describes a mans inability to achieve and maintain an erection of his penis sufficient for mutually satisfactory intercourse with his partner.
In general, the cause of erectile dysfunction is divided into 2 types:
Psychological (mental) causes
Physical or organic (having to do with a bodily organ or an organ system) causes
Psychological Causes
Erection problems usually produce a significant psychological and emotional reaction in most men. This is often described as a pattern of anxiety and stress that can further interfere with normal sexual function. This "performance anxiety" needs to be recognized and addressed by your doctor.
For some men, erectile dysfunction develops with age or may be related to depression or another psychological cause, such as widower syndrome.
Certain feelings can interfere with normal sexual function, including feeling nervous about or self-conscious about sex; feeling stressed either at home or at work; or feeling troubled in your current relationship. In these cases, psychological counseling with you and your sexual partner may be successful. One episode of failure, regardless of cause, may propagate further psychological distress leading to further erectile failure.
Physical (Organic) Causes
In determining a physical (or organic) cause, your doctor will first rule out certain conditions, such as high blood pressure, high cholesterol, heart and vascular disease, low male hormone level, prostate cancer, and diabetes, which are associated with erectile dysfunction.
Medications
Medications used to treat other medical disorders may cause erectile dysfunction. If you think erectile dysfunction is caused by a medication, talk with your doctor about drugs that might not cause this side effect. Do not just stop taking a prescribed medication before talking with your doctor. Common medications associated with erectile dysfunction are:
Antidepressants (for depression)
Antipsychotics (for psychological illness)
Antihypertensives (for high blood pressure)
Antiulcer drugs, such as cimetidine (Tagamet)
Alcohol abuse
Mind-altering agents, such as marijuana and cocaine
Performance anxiety:
Most men have had erection problems at some point due to worrying about performing well during sexual intercourse. If this happens often, the anticipation of sex can trigger nervous reactions that prevent erection, setting up a vicious cycle.
Symptoms and Complications of Erectile Dysfunction
When a man is unable to get or maintain an erection, it is termed erectile dysfunction. It may also be called erectile difficulties.
A man may sometimes have erections, (e.g., when he wakes up in the morning), but be unable to get an erection during sex with his partner. This is often a sign of a psychological problem that may or may not have to do with that particular relationship.
If a man had regular erections in the past, but suddenly begins to have problems getting an erection, there's a chance that it's a nerve or hormonal problem, a circulatory problem, or the effect of alcohol, drugs, or medicine.
If a man still gets erections but they're not as hard or long lasting as in the past, it's quite likely that a circulatory problem is causing the dysfunction.
If surgery or injury is involved, the sufferer may already know what's causing the erectile dysfunction. A doctor should be consulted about possible solutions.
While erectile dysfunction is inevitably going to cause some anxiety, it's vital for sufferers to keep their relationship with their partner or spouse as regular as possible until a solution can be found. Modern medicine and therapeutic techniques can help over 90% of erection problems.
Treating and Preventing Erectile Dysfunction
There's a wide range of treatments for erectile dysfunction. Some are pills, and others are injections or devices that should be used just before sex. There are also treatments involving surgery.
Medications for erectile dysfunction include phosphodiesterase inhibitors, prostaglandins, and testosterone.
Phosphodiesterase inhibitors: This class of medications includes sildenafil,* tadalafil, and vardenafil. They work by inhibiting an enzyme called phosphodiesterase type 5 (PDE-5). This enzyme normally breaks down a molecule called cGMP. Inhibiting the enzyme makes more cGMP available, which leads to relaxation of smooth muscles in the penis, allowing more blood to enter and helping to produce an erection. These medications are taken before sex and will cause an erection only when the man is sexually stimulated.
The time the dose should be taken and how long the effects last depend on the medication used. The most common side effect of these medications is a headache. However, there is a potential for certain dangerous drug interactions. Anyone taking this medication must let his doctor know about any medications he's on, and especially if he's taking nitrates (e.g., nitroglycerin spray or nitroglycerin patch) for heart problems.
Prostaglandins (alprostadil): Alprostadil can be injected into the penis or inserted as a pellet through the urethra. It causes an erection that usually lasts about 60 minutes. The danger with this method is that too high a dose can cause priapism, an erection that won't go away. This condition can cause serious bruising, bleeding, and pain. Once the doctor is sure of the right dose, the man can self-inject at home.
Some doctors may prescribe a combination of alprostadil with additional ingredients such as phentolamine to help the medication work more effectively. This mixture is prepared by the pharmacy according to the directions of the prescribing doctor. It is injected into the penis before sex.
Testosterone: This is only useful for people with specific disorders like hypogonadism (small testicles at birth) that result in lower than normal amounts of testosterone in the blood stream. Testosterone increases interest in sex, as well as erections.
Common non-medication ways of treating erectile dysfunction include vacuum devices and penile implants.
Vacuum devices: This involves placing a tube over the penis, forming an airtight seal around the base. By pumping air out of the tube, blood can be drawn into the penis. Placing a ring around the base of the penis will maintain the erection.
