Preclinical and clinical trials of these oral agents have clearly demonstrated that they are well tolerated by most DM patients and have an efficacy rate superior to other oral agents. The ultimate result is an improved quality of life (QOL) in EDDM patients. With a greater willingness of DM patients to discuss and seek treatment for ED, it is highly probable that the use of these oral agents will continue to increase. The goal of this article is to provide the physician and pharmacist with a background and working knowledge of these oral agents and their present-day alternatives.
Actually the first simple step to managing your blood pressure is to start tracking it! Get an inexpensive blood pressure cuff at CVS or on Amazon. Download the free Hello Heart app (iOS, Android) from the iTunes Store and Google Play. Start recording your daily blood pressure. Just the simple act of daily recording can have a very beneficial effect.
A man needs to try the medicine at least four times before he concludes that it doesn’t work for him. It is unlikely that a man with diabetes who has other medical problems such as high blood pressure, is taking multiple medicines, and has not had sexual intercourse for several years will be able to have an erection adequate for intercourse the first time he takes a pill. Most men need to try the medicine several times before they have the desired results.
A medical history focused on risk factors, such as cigarette smoking, hypertension, alcoholism, drug abuse, trauma, and endocrine problems including hypothyroidism, low testosterone levels, and hyperprolactinemia, is very important. Commonly used drugs that disrupt male sexual function are spironolactone (Aldactone), sympathetic blockers such as clonidine (Catapres), guanethidine (Islemin), methyldopa (Aldomet), thiazide diuretics, most antidepressants, ketoconazole (Nizoral), cimetidine (Tagamet), alcohol, methadone, heroin, and cocaine. Finally, assessment of psychiatric history will help identify emotional issues such as interpersonal conflict, performance anxiety, depression, or anxiety.
The natural history of ED in people with diabetes is normally gradual and does not occur overnight. Both vascular and neurological mechanisms are most commonly involved in people with diabetes. Atherosclerosis in the penile and pudendal arteries limits the blood flow into the corpus cavernosum. Because of the loss of compliance in the cavernous trabeculae, the venous flow is also lost. This loss of flow results in the inability of the corpora cavernosae to expand and compress the outflow vessels.
The initial event for normal erectile function is sexual stimulation. Subsequent to processing in the central nervous system neural impulses are conveyed along the spinal cord, exiting through the pelvic parasympathetic preganglionic nerves. These pelvic nerves form the pelvic plexus and send their message through first messenger, acetyl choline, to the cavernosal nerves. The cavernosal nerves enter erectile bodies (corpora cavernosa) (Figure 1). Here, their nerve endings release a second messenger, nitric oxide. Nitric oxide activates the enzyme guanylyl cyclase, which lyses guanosine triphosphate (GTP) to produce a third messenger, the intracellular cyclic guanosine monophosphate (cGMP). Ultimately, the result is a decrease of intracellular calcium and an opening of potassium channels with the resultant relaxation of vascular smooth muscle in the arteries, aterioles, and sinusoids of the corpora cavernosa. The sinusoids open and rapidly fill with blood. Finally, the distended sinusoids compress their drainage pathways (venules) against the fibroelastic covering of the cavernosal bodies (tunica albuginea) and trap the blood in cavernosal bodies. The combination of an increased inflow of blood into the penis and coincident markedly diminished outflow results in rapidly increasing intracavernosal pressure that ultimately approximates systolic pressure. At this pressure the penis has sufficient axial rigidity to permit vaginal penetration.
There are a number of reasons a man may not achieve the desired result from an oral erectile dysfunction drug. In some cases, a man may experience drug side effects severe enough to outweigh any potential benefit of taking the drug. Possible side effects of these drugs include headache, facial flushing, nasal congestion, and transient abnormal vision. (In October 2007, the FDA added a warning about sudden hearing loss to the package labels of oral erectile dysfunction drugs. While it’s not absolutely clear that the drugs can cause sudden hearing loss, a number of cases have been reported in men within hours or days of taking one of the drugs.)