Brad Butt takes a look at the causes and treatments for ED… and why conversations with pharmacists can help
Many men report symptoms of erectile dysfunction (ED) at one time or another in their lives; it can certainly come and go. This aside, it is generally estimated that it affects around 1 million Australian men on an ongoing basis.
Also known as impotence, ED means not being able to get or keep an erection that is sufficient for sexual intercourse. It is worth noting that it can have a range of causes, both physical and psychological and without carefully considering the etiology medication optimisation may not be achieved.
Physical factors include, but are not limited to things like general ageing, conditions affecting the nerves (spinal cord injury, multiple sclerosis, Parkinson’s disease, Alzheimer’s disease and motor neurone disease), surgery and/or radiation to the pelvic area (prostate or bowel surgery), and then the usual suspects including diabetes, smoking, hypertension, obesity, medications (including but not limited to antidepressants, antihypertensives, prostate cancer/benign prostatic hyperplasia medications), hypercholesterolemia, hypothyroidism, low testosterone, alcohol intake and substance abuse. This list, whilst exhausting, is not exhaustive.
Psychological factors on the other hand may include issues within a sexual and/or emotional relationship, stress at home, school or work, mental health deterioration (most commonly depression) and perhaps the largest psychological factor; that being anxiety about sexual performance (particularly in a new relationship or where a man has had previous problems with sexual performance).
As we all well know the treatments for erectile dysfunction have not changed a great deal since the launch of the PDE5i wonder drug Viagra back in 1998. Prior to that, options were quite limited and generally confined to Caverject (lanuched late 1980’s early 1990’s) and the intrauretheral pelets (MUSE).
Today we are fortunate to have four oral PDE5i on the market including the most recent addition to the stable, avanafil, which has a strong affinity for the receptor and benefits around its onset of action and faverouble side effect profile.
There will, however, always be a need for intracavernosal therapies and of these Caverject is the best known and most widely used.
It is worth remembering that PDE5is works by binding to an enzyme called phosphodiesterase. All PDE5is bind to the enzyme and prevent it from converting the chemical cyclic guanosine monophosphate (cGMP) into guanosine triphosphate (GTP).
The effect of cGMP building up is the dilation of artery walls thus allowing more blood to flow into the penis.
Of course, these medications will not give the patient an erection without sexual stimulation; with arousal the brain sends a signal to the cells in the penis to release nitric oxide, which turns on the production of cGMP. Without the stimulation to produce nitric oxide, there is no cGMP build-up and no erection.
This inability of the brain to send a signal to the penis is precisely why men who have had surgery or radiation to their pelvic area generally do not respond to oral PDE5is and equally why they might have to use ICI – delivering the medication direct to the area it needs to be to illict its response.
With ED affecting so many men in all of our pharmacies, having a good baseline knowledge is half the battle; the other half is identifying the right patient at the right time to have a conversation and then doing it with care and a genuine desire to help.
Brad Butt is a passionate community pharmacist with a strong clinical background who takes pride in supporting the health of his patients and the wider community; special interests include Men’s Health, childhood and maternal health, palliative care and the treatment and management of blood cancers.