In subsequent clinical studies, a surprisingly high percentage of EDDM patients–10% to 20%–claimed that the placebo "improved my erections," thus indicating a psychological basis for their ED. In the latter half of the 1980s, objective means were developed that could help determine if a EDDM patient had organic or psychogenic ED. The absence of rigid sleep erections confirmed by penile monitors was one criterion for organic ED. The failure of vasoactive agents (papaverine, Trimix, or prostaglandin E-1 [PGE-1]) injected into the corpora cavernosa to induce penile rigidity was another criterion for organic disease. Intracavernosal maintenance flow rates during pharmacocavernosometry and maximum cavernosal arterial flow during penile Doppler ultrasonography were additional determinants.

In the vessels that supply the heart, healthy arteries enlarge in diameter up to 50% during exercise when sufficient nitric oxide is present. Because of its brief half-life, a continual supply of nitric oxide is required for optimal effect. If the supply of nitric oxide is inadequate, endothelial dysfunction—a core factor in heart disease—is made worse. Endothelial dysfunction can trigger the growth of coronary plaque.8
DHEA. Testosterone is essential for a healthy libido and normal sexual function, and erectile dysfunction sufferers known to have low testosterone improve when placed on prescription testosterone replacement therapy. Similarly, studies have shown that taking over-the-counter supplements containing DHEA, a hormone that the body converts to testosterone and estrogen, can help alleviate some cases of ED. But DHEA can cause problems, including suppression of pituitary function, acne, hair loss and its long-term safety is unknown, says McCullough. For this reason, many experts discourage use of the supplements.
Abstract | PubMed | Scopus (136) | Google ScholarSee all References In a prospective review of 3250 men aged 26 to 83 years without ED at their first examination, total cholesterol and high-density lipoprotein (HDL) cholesterol levels were found to be strongly predictive of onset of ED after controlling for age, diabetes mellitus, stress level, cardiovascular disease, and prostate disease.25x25Wei, M, Macera, CA, Davis, DR, Hornung, CA, Nankin, HR, and Blair, SN. Total cholesterol and high density lipoprotein cholesterol as important predictors of erectile dysfunction. Am J Epidemiol. 1994; 140: 930–937
Phosphodiesterase Inhibitors. The cornerstone of first-line therapy is the PDE-5 inhibitor. No other class of oral agents approaches the efficacy of PDE-5 inhibitors. Yohimbine, trazodone, phentolamine, L-arginine, and OTC herbal remedies have been used with very limited success. The superiority of yohimbine over placebo in the treatment of organic ED is a matter of dispute.9 A recent trazodone study failed to detect any difference between trazodone and placebo on sexual function.10 Oral phentolamine, although available in Mexico, has not been approved by the US FDA for the treatment of ED. Apomorphine, a central dopaminergic receptor drug, has recently been voluntarily withdrawn from FDA consideration for the treatment of ED. The efficacy of ginkgo biloba and Korean red ginseng has yet to be demonstrated by randomized, placebo-controlled trials.
Yohimbine: The main component of an African tree bark, yohimbine is probably one of the most problematic of all natural remedies for ED. Some research suggests that yohimbine can improve a type of sexual dysfunction that is linked with a drug used to treat depression. However, studies have linked yohimbine to a number of side effects, which can include anxiety, increased blood pressure, and a fast, irregular heartbeat. Like all natural remedies, yohimbine should only be used after advice and under supervision from a doctor.
Although a considerable number of patients report penile pain with IC injection therapy, it appears that diabetic men still have high compliance rates with therapy. In one study, 16 of 18 diabetic men continued IC injection therapy for 7 years, compared to 7 of 22 nondiabetic control subjects with ED.57 One possible explanation for this is that diabetic patients with ED have fewer options than do nondiabetic men with ED, who are more likely to have a successful response to oral PDE-5 agents, as documented in one study.58 Another explanation is the greater familiarity with needles and injections among men with diabetes than among their nondiabetic counterparts.

Apart from their beneficial effect in erectile dysfunction and their safe profile in antihypertensive medication, PDE-5 inhibitors have even more advantages to demonstrate. Several lines of evidence has proven that patients receiving PDE-5 inhibitors are more likely to initiate an antihypertensive regime and more willing to add a new agent to their existing treatment, a fact that raises significantly patient’s adherence and as a matter of fact control of high blood pressure and quality of life[63,64]. Moreover, a handful of clinical data has demonstrated the considerable vasodilating and anti-proliferative properties of PDE-5 inhibitors in the pulmonary vasculature, establishing them as a first-line treatment in patients with pulmonary arterial hypertension[65,66]. The same properties have been considered as potentially responsible for improving microcirculation in patients with secondary Raynaud phenomenon and ameliorating cardiopulmonary exercise performance in patients with heart failure[67,68]. In addition, the therapeutic implementation of PDE-5 inhibitors has expanded in the field of benign prostate hyperplasia-lower urinary tract symptoms (BPH-LUTS). The common pathophysiologic substrate between erectile dysfunction and BPH-LUTS has rendered PDE-5 inhibitors an effective treatment which significantly improves measures of both conditions while at the same time exhibits high efficacy and safety. The beneficial effect is much more pronounced when taking into consideration the fact that a-blockers, the mainstay of therapy for benign prostate hyperplasia frequently provoke sexual side effects, erectile dysfunction included[69].


Erectile dysfunction (ED) is a common sexual problem affecting many men irrespective of cultures, beliefs and nationalities. While medical therapy for ED has been revolutionized by the advent of oral phosphodiesterase type 5 inhibitors and intracavernosal injection of vasoactive agents, recent technological advances such stem cell therapy, low intensity shock wave and newer generation of penile prosthesis implant offer hope to men who do not respond to conventional medical therapy. In contrast, traditional and complementary medicine (TCM) focuses on the restoration and better overall bodily regulation with the use of various herbal and animal products as well as exercises to invigorate qi (energy) in vital organs. Western medicine involves an analysis of ED symptom and underlying causes that contribute to ED, while TCM emphases the concept of holism and harmonization of body organs to achieve natural sexual life. The following article reviews our current understanding regarding the philosophical approach, and evaluates the evidence surrounding various ED therapies between mainstream Western Medicine and TCM.
Relaxation of erectile tissue requires nitric oxide from nonadrenergic-noncholinergic neurons and the endothelium.21 Penile tissue from diabetic men with ED demonstrates impaired neurogenic and endothelium-mediated relaxation of smooth muscle,22 increased accumulation of advanced glycation end products (AGEs),23 and upregulation arginase, a competitor with nitric oxide synthase for its substrate L-arginine.24 Normal responses to direct smooth muscle relaxants in most of these studies implies that the impairments are due to decreased synthesis, release, or activity of nitric oxide. The fundamental mechanisms mediating these changes are thought to be the same as for other diabetic complications: increased polyol pathway flux, intracellular accumulation of AGEs, activation of protein kinase C, and increased flux through the hexosamine pathway.25
Experimental hyperglycemia may also affect cavernosal smooth muscle cell contractile responses. In experimental diabetes, penile smooth muscle has augmented force responses to vaconstrictors, possibly mediated by changes in expression of protein kinase C and the RhoA-Rho kinase Ca2+-sensitization pathway.32 These changes may promote flaccidity and alter the relaxation responses to nitric oxide. End-stage penile dysfunction may occur as a result of diabetes, with progressive loss of normal cavernosal endothelium and smooth muscle cells from the corpus cavernosum.33 Replacement by fibrotic tissue may lead to complete erectile failure.34
Not enough info for you? No problem. Nerd out on erectile dysfunction with these studies and research from the most trusted sources on the interwebs. If you have any questions or you think we missed something important, leave a comment or book a consultation with me or one of these trained professionals and we’ll get you on the way to a healthier manhood.

Few simple laboratory tests can help identify obvious causes of organic ED. Initial labs should include HbA1c, free testosterone, thyroid function tests, and prolactin levels. However, patients who do not respond to pharmacological therapy or who may be candidates for surgical treatment may require more in-depth testing, including nocturnal penile tumescence testing, duplex Doppler imaging, somatosensory evoked potentials, or pudendal artery angiography.
The Massachusetts Male Aging Study of 1,290 men, aged 40–70 years, has documented the extraordinarily high prevalence of erectile dysfunction among aging men: 50% of men at 50 years of age, and 70% by age 70 have erectile dysfunction.2 Furthermore, a recent Italian study of men with severe heart disease has uncovered an astounding 93% with erectile dysfunction 24 months before their heart attack or onset of heart disease symptoms.3
“The presence of erectile dysfunction portends a higher risk of future cardiovascular events, particularly in intermediate-risk men, and may serve as an opportunity for intensification of cardiovascular risk prevention strategies,” wrote Boston University heart specialists Naomi Hamburg, MD and Matt Kluge, MD, in an accompanying editorial. “The findings add to the growing evidence supporting additional trials to determine the clinical impact of erectile dysfunction screening and the appropriate cardiovascular directed evaluation and treatment of men with erectile dysfunction.”
If you bike a lot and have a very narrow saddle on your bicycle, consider switching to a "no-nose seat" which is wider at the back than a conventional saddle, allowing more of your weight to be distributed to the sitting bones. Make sure the seat is level or angled slightly downward and at a height that allows your knee to be just slightly bent at the bottom of the pedal cycle. Raising the handlebars on your bike so that you're sitting upright may also help.
Yohimbine: The main component of an African tree bark, yohimbine is probably one of the most problematic of all natural remedies for ED. Some research suggests that yohimbine can improve a type of sexual dysfunction that is linked with a drug used to treat depression. However, studies have linked yohimbine to a number of side effects, which can include anxiety, increased blood pressure, and a fast, irregular heartbeat. Like all natural remedies, yohimbine should only be used after advice and under supervision from a doctor.
Cardiovascular tolerance for sex is based on “functional reserve,” which corresponds to how closely the cardiovascular response to sex (in terms of heart rate, blood pressure level, and oxygen consumption) approaches the patient's peak response to exercise.85x85DeBusk, RF. Evaluating the cardiovascular tolerance for sex. Am J Cardiol. 2000; 86: 51F–56F
Mancia G,  Laurent S,  Agabiti-Rosei E,  Ambrosioni E,  Burnier M,  Caulfield MJ,  Cifkova R,  Clément D,  Coca A,  Dominiczak A,  Erdine S,  Fagard R,  Farsang C,  Grassi G,  Haller H,  Heagerty A,  Kjeldsen SE,  Kiowski W,  Mallion JM,  Manolis A,  Narkiewicz K,  Nilsson P,  Olsen MH,  Rahn KH,  Redon J,  Rodicio J,  Ruilope L,  Schmieder RE,  Struijker-Boudier HA,  van Zwieten PA,  Viigimaa M,  Zanchetti A. European Society of HypertensionReappraisal of European guidelines on hypertension management: a European Society of Hypertension Task Force document, J Hypertens , 2009, vol. 27 (pg. 2121-2158)https://doi.org/10.1097/HJH.0b013e328333146d
Not enough info for you? No problem. Nerd out on erectile dysfunction with these studies and research from the most trusted sources on the interwebs. If you have any questions or you think we missed something important, leave a comment or book a consultation with me or one of these trained professionals and we’ll get you on the way to a healthier manhood.
Vacuum therapy devices have a few disadvantages. One must interrupt foreplay to use them. You must use the correct-size tension ring and remove it, to prevent penile bruising, after sustaining the erection for 30 minutes. Initial use may produce some soreness. Such devices may be unsuitable for men with certain bleeding disorders. In general, vacuum constriction devices are successful in management of long-term ED.
Abstract | Full Text PDF | PubMed | Scopus (1528) | Google ScholarSee all References After sexual intercourse, this risk increases approximately 2-fold, to 2 chances per million per hour, but only for the 2 hours after intercourse. For low-risk patients with no history of cardiovascular disease and an annual myocardial infarction risk of 1% per year, the risk increases to 1.01% with weekly sexual activity.8x8Muller, JE, Mittleman, A, Maclure, M, Sherwood, JB, Tofler, GH, and Determinants of Myocardial Infarction Onset Study Investigators. Triggering myocardial infarction by sexual activity: low absolute risk and prevention by regular physical exertion. JAMA. 1996; 275: 1405–1409
The medications used to treat high blood pressure do not take into account the symptoms of erectile dysfunction, as their intention is to lower the blood pressure to a more manageable state, reducing the stress put on blood vessels. High blood pressure and ED are seen as separate entities, with the former taking priority for pharmaceutical treatment. This means that the medications used might do nothing to cure erectile dysfunction and may, in fact, prolong it. Medications that lower blood pressure might actually cause a low blood pressure state in the groin area and the arteries supplying the penis, making it near impossible to achieve an erection. The following are examples of such medications:
Dr. Eid also urges these patients to treat their diabetes in order to avoid developing ED for life. “They need to manage their diabetes and make sure they control it so the ED will not progress and will stabilize, as a result,” he said. “If the diabetes is controlled after the patient is first diagnosed, then the erections will come back. But if the patient has diabetes for many years, and suddenly decides it’s time to control it, they cannot prevent the damage that’s already been done.”
In many of these cases, a discussion between the physician, the man with erectile dysfunction, and possibly his partner can help to resolve the issues leading to treatment failure. For men who experience severe side effects, can’t take the drugs for other reasons (such as taking medicines such as nitroglycerin), or don’t respond in spite of further education on the correct use of the drugs, there are other treatment options that can help most men remain sexually active.
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