Providence St. Joseph Medical Center
Erectile dysfunction (ED) is a very common disorder that affects up to half the male population over the age of 40. As one might expect, the degree of severity of ED can range from minimal in younger age groups to severe dysfunction in older age groups. Generally, ED is defined as a difficulty in attaining and maintaining an erection sufficient for satisfactory penetrative intercourse. Unfortunately, despite aggressive marketing by pharmaceutical companies to both physicians and patients, most men never receive treatment.
The causes of ED can be multifactorial, but generally are divided into 3 categories: those resulting from vascular causes, such as high blood pressure and atherosclerosis (hardening of the arteries); neurogenic causes, such as spinal cord injuries; and psychogenic causes, such as chronic depression. Of course, some causes such as diabetes can damage both nerves and blood vessels, leading to both neurogenic and vasculogenic ED. Medications, such as beta blockers used to treat high blood pressure, will often exacerbate underlying ED. Patients should consult with their doctors about changing their medications so that their underlying condition can be treated effectively while minimizing side effects such as ED. Finally, it should be noted that one of the most common and most reversible causes of ED is tobacco smoking. Studies have shown that moderate to severe ED is two times more common among smokers than non-smokers. Cessation of smoking can often result in improvement of erections within a week.
Among male multiple myeloma patients, recent anecdotal reports are revealing an even greater prevalence in this select population. The causes are not known, but undoubtedly include the impact of the underlying myeloma, with changes in hormone levels, and the effects of various new treatments, including such drugs as thalidomide. Thalidomide can cause a side effect known as neuropathy, which typically leads to problems of sensation that can range from numbness to muscle cramping and pain. However, men taking thalidomide generally do not report problems of penile sensation, but rather can experience difficulty attaining and maintaining erections.
Fortunately, a variety of treatment options exist for the treatment of ED. The relatively recent introduction of a new class of medications known as PDE5 inhibitors (Viagra®, Levitra®, Cialis®) has transformed ED from a condition that was difficult to treat, to one that is more often treatable. PDE5 is an enzyme that effectively causes the erectile bodies inside the penis to contract and therefore precludes a normal erection. Thus, by inhibiting PDE5, the erectile chambers can dilate and engorge with blood to allow for a complete erection. Viagra is probably the best-known PDE5 inhibitor since it was the first drug of this class to be launched. Patients should take this medication preferably on an empty stomach since food will impair its absorption. The peak time of action is roughly 2 hours after taking the drug, so a man will need to anticipate his sexual activity. Similarly, Levitra also has a peak time of action at approximately 2 hours after taking the drug. However, unlike Viagra, a full stomach will not impair absorption of Levitra. The most recent PDE5 inhibitor introduced is Cialis, which remains effective for up to 36 hours. This means that, with sexual stimulation, a man can have an erection anytime within the 36-hour window. Indeed, all of these medications require some form of arousal or foreplay for an erection to be achieved. As with all mediations, PDE5 inhibitors can occasionally cause side effects, including nasal congestion, visual changes, and rarely, muscle aches. Because the PDE5 inhibitors are systemic drugs, patients should check with their doctors about both drug interactions and other medical considerations. For myeloma patients, underlying kidney impairment will require appropriate dose adjustment.
Prior to the introduction of PDE5 inhibitors, the treatment of ED was more limited. Many of these older treatments are still useful, however, since some men cannot tolerate the newer oral drugs or may need some form of combination treatment. Caverject® is a medication that is injected directly into the side of the mid-shaft of the penis through a very fine needle. Muse® is a similar medication that is inserted via a small pellet into the urethral meatus, the small opening at the tip of the penis through which urine exits. Another option is the vacuum erection device, or VED. This method creates a vacuum with a plastic cylinder that is placed around the penis such that blood is drawn into the erectile chambers and trapped to cause an erection. There is a variety of other older methods that may offer benefits to patients who cannot tolerate the newer treatments.
The good news for patients is that there is a wide range of treatment options for ED. Patients should feel comfortable discussing this issue with their physicians and have confidence that very likely there is a medication that will alleviate this condition.