Crossref | PubMed | Scopus (697) | Google ScholarSee all References Subsequent in vitro electrical stimulation of these tissue samples showed decreased neurogenic and endothelium-dependent smooth muscle relaxation in the tissue from the patients with diabetes. These effects persisted even after controlling for smoking and hypertension. Other studies have shown a heightened smooth muscle tone in patients with diabetes mellitus.24x24Christ, GJ, Stone, B, and Melman, A. Age-dependent alterations in the efficacy of phenylephrine-induced contractions in vascular smooth muscle isolated from the corpus cavernosum of impotent men. Can J Physiol Pharmacol. 1991; 69: 909–913
The initial step in evaluating ED is a thorough sexual history and physical exam. The history can help in distinguishing between the primary and psychogenic causes. It is important to explore the onset, progression, and duration of the problem. If a man gives a history of “no sexual problems until one night,” the problem is most likely related to performance anxiety, disaffection, or an emotional problem. Aside from these causes, only radical prostatectomy or other overt genital tract trauma causes a sudden loss of male sexual function.
Organic nitrates are drugs that widen arteries by increasing their supply of nitric oxide; that's how they open the partially blocked coronary arteries in patients with angina. But because nitrates and ED pills both act on nitric oxide, the drugs don't mix; healthy volunteers given Viagra followed an hour later by nitroglycerin see their blood pressures drop by 25–51 mm Hg, a potentially dangerous amount. All experts agree that men who are taking nitrates cannot use ED pills; this includes all preparations of nitroglycerin (short-acting, under-the-tongue tablets or sprays), long-acting nitrates (isosorbide dinitrate or Isordil, Sorbitrate, and others, and isosorbide mononitrate, Imdur, ISMO, and others), nitroglycerin patches and pastes, and amyl nitrite or amyl nitrate (so-called poppers, which some men use for sexual stimulation).
There’s one more thing to remember: A visit to a physician can be helpful even if a man doesn’t want to go near Viagra or try one of the alternatives. In some cases, a treatable medical condition such as low testosterone or depression could explain a case of ED. “Sexual health should not be viewed as a luxury, but rather as an essential component to wellness,” said urologist Ryan P. Terlecki, MD, of Wake Forest Baptist Health in North Carolina.