Erectile Dysfunction

Erection problems.

And so the demand for effective treatment for erectile dysfunction is going to increase in years to come. One of the major ways to treat ED is  pharmacological agents, i.e., prescription drugs like Viagra and Cialis.

The frequency of erection problems is high: even among normal men it is estimated that about 1 man in 12 has an erection problem. Among diabetic men, the frequency is much higher – up to 50 % of men with diabetes have some kind of erection problem.

What is erectile dysfunction (ED)? How is it treated with drugs?

Erectile dysfunction is defined very simply: a man can’t get an erection hard enough to sustain sexual intercourse. There are other related conditions, such as diminished libido (low sex drive or lack of desire), low testosterone. Also, delayed ejaculation, or DE – see a good book on this here – or premature ejaculation may be associated with erection problems. (Read more about delayed ejaculation here.)

ED or erectile dysfunction increases in frequency in the older age groups. This can be caused by circulation problems, nerve problems, hormonal problems, psychological issues, or prescription drugs.  But most often it is down to a combination of one or more of these factors. (Which are also called, in the order referred to above, vasculogenic, neurogenic, endocrine, psychogenic, and prescription drug induced.)

There’s no hard and fast classification of what constitutes and erection problem, or a definition of erectile dysfunction. The condition itself ranges from an erection that is not firm enough for intercourse to an erection which allows penetration but then fades away. Alternatively and erection may not last long enough for intercourse to be completed.

(By the way, surgery is not such a good option; the implantation of a prosthetic inflatable device is major surgery, with attendant risks, and has a high failure rate.)

By contrast, one of the main avenues of treatment over the past ten years has been by drugs such as Viagra. The rapid response and effective action of these drugs is important. They represent an instant treatment for a man who is unable to have sex, and thereby provide a rapid boost to self-esteem and sexual self-confidence. This will reduce the feelings of anger, depression and low self-esteem so common among men with ED.

How does drug treatment for Erectile Dysfunction (ED) work?

The erectile chambers of the penis consist of two longitudinal structures (each called a corpus cavernosum) which run along the length of the penis from its base to the coronal ridge. These corpora cavernosa are made up of spongy tissues surrounded by smooth muscle.

Normally, a degree of muscle tone keeps the muscles fibres slightly tense, thereby preventing blood flowing into the expandable tissues. When the muscles relax, blood may enter, and the tissues swell, which has the effect of squeezing the veins leading blood away from the penis.

(The veins are squeezed between the rather inelastic tunica albuginea which surrounds the whole of the erectile tissue and the corpora cavernosa.) With blood unable to drain away, the penis becomes erect. This process is far from simple, and involves many chemicals, nerve impulses and interacting somatic and chemical factors. Disruption to any part of the process may cause a man to develop erectile dysfunction.

Causes of erectile dysfunction


The most common factor is vascular: a problem with either the veins or the arteries of the penis. Clearly either impaired arterial function (arterial insufficiency) or a leaking vein (veno-occlusive erectile failure) may contribute to erection problems. Such problems originate in conditions such as hypertension, hyperlipidemia, diabetes and smoking.


But neurological problems are also a common cause of impotence. Nerve impulses resulting from sexual stimulation cause the release of nitric oxide and prostaglandins in the base of the penis. These substances then cause the smooth muscles of the penis to relax and allow blood to flow in, thereby causing an erection to develop. Injury to any part of the nerve network that promotes these chemical actions can render a man impotent. Such damage can result from groin injury, prostate surgery, MS, and neuropathy associated with diabetes.


Testosterone declines with age – as most men over 50 years of age will know – and this reduction in blood testosterone may result in fewer night-time erections and a lower level of libido. There are also a number of medications which may produce high prolactin levels, which antagonizes the action of testosterone. See below for more on this.


These include SSRIs (prescribed for mood disorders) and ranitidine (prescribed for stomach acid problems). In addition, some antihistamines, antidepressants, antihypertensives, sedatives and anxiolytics (anti-anxiety drugs) have been all been blamed for causing erection problems.

Stress, anxiety and other psychological factors 

Stress and anxiety can produce erectile dysfunction by raising blood catecholamine levels – these stress hormones oppose smooth muscle relaxation.

Purely psychological factors may include fear of sex, fear of women, fear of pregnancy, fear of failure and so forth. The inability to get erect causes much anxiety, which in itself is likely to cause erectile failure at the next sexual situation, thereby perpetuating and compounding the erectile dysfunction.

Treatment Options for Erectile Dysfunction 

Treatment may involve both the man and his partner: ED is generally not a problem that occurs in isolation.

You can enjoy a better erection by engaging with your partner in a series of exercises which resemble those prescribed by the professional sex therapists. These are described in this book on erectile dysfunction, which you can get from and

Penile prostheses and erectile dysfunction

These are inflatable or semi-rigid devices which are implanted into a man’s penis in place of his own erectile tissue. There has historically been a fairly high failure and infection rate. A more modern form of surgery for impotence is surgery to improve the flow of blood to the penis. This can be successful when the surgeon is experienced and the patient is properly selected.

A penile support sleeve to improve erectile firmness

A support sleeve may allow penetration of a soft penis into the vagina but who knows how much pleasure it gives either partner? Read more here.

Pharmacologic agents and the treatment of ED

Vasoactive agents like Viagra and Cialis will relax the blood vessels of the penis and permit the accumulation of more blood in the corpora cavernosa.

Other drugs used from time to time to treat ED have included Yohimbine, which is an alpha-2-adrenergic blocking agent. The effectiveness of Yohimbine as a treatment for erectile dysfunction has not been proven, and as it tends to promote anxiety and high pulse rates in susceptible men. It is really a treatment of limited benefit, especially now that Viagra has been proven safe and successful.

Psychological or physical erectile dysfunction?

Psychological issues are probably involved in all cases of erectile dysfunction: if not before it develops, certainly after it has done so! But for erectile problems that have a purely psychological origin (e.g. anxiety, nervousness, anger), the onset of erectile dysfunction is sudden and unexpected. In the case of physical erectile dysfunction, in other words that caused by an underlying physiological problem, the onset may be more gradual.