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.

Penile Injection Medication: This is just what it sounds like. Injected at home directly into the penis, the medication alprostadil produces erection by relaxing certain muscles, increasing blood flow into the penis and restricting outflow. Although some sources report an 80 percent success rate, the therapy has disadvantages, such as risks of infection, pain, and scarring—fibrosis—in the penis, and it may also cause priapism. A popular version of this medication is Upjohn Corporation’s Caverject. The MUSE System, by VIVUS, involves the same medicine (a pellet of alprostadil) applied with an eye-dropper-like applicator, directly into the urethra.


In an open-label study, 8 patients monitored with a Swan-Ganz catheter were given a total of 40 mg of sildenafil in 4 intravenous transfusions (the equivalent of 1 to 3 times the plasma concentration after an oral dose of 100 mg).62x62Jackson, G, Benjamin, N, Jackson, N, and Allen, MJ. Effects of sildenafil citrate on human hemodynamics. Am J Cardiol. 1999; 83: 13C–20C
Abstract | Full Text | Full Text PDF | PubMed | Scopus (95) | Google ScholarSee all References Another contraindication is the use of recreational drugs (“poppers”) that contain amyl nitrate. The guidelines also caution use in patients who have a high risk of cardiovascular effects, including patients with active coronary artery disease who are not taking nitrates, patients with congestive heart failure with a borderline low blood pressure level and low blood volume, or those with complicated multidrug antihypertensive regimens.
Taking one of these tablets will not automatically produce an erection. Sexual stimulation is needed first to cause the release of nitric oxide from your penile nerves. These medications amplify that signal, allowing some men to function normally. Oral erectile dysfunction medications are not aphrodisiacs, will not cause excitement and are not needed in men who get normal erections.
In the past 6 years, the FDA has approved three oral agents for the treatment of ED: sildenafil, vardenafil, and tadalafil. All three are phosphodiesterase type 5 (PDE-5) inhibitors and work by potentiating the effect of nitric oxide in the penis. In particular, they block the hydrolysis of cyclic guanosine monophosphate to guanosine 5'-monophosphate, thus enhancing nitric oxide–mediated smooth muscle relaxation, increasing blood flow to the penis and facilitating erection.
Current American College of Cardiology/American Heart Association guidelines quote an absolute contraindication to sildenafil use in the setting of chronic nitrate treatment or the use of short-acting nitrate medications.10x10Kloner, RA and Zusman, RM. Cardiovascular effects of sildenafil citrate and recommendations for its use. Am J Cardiol. 1999; 84: 11N–17N
Sexual dysfunction is a common, underappreciated complication of diabetes. Male sexual dysfunction among diabetic patients can include disorders of libido, ejaculatory problems, and erectile dysfunction (ED). All three forms of male dysfunction can cause significant bother for diabetic patients and can affect their quality of life. Despite this, health care providers often do not specifically ask their male diabetic patients about sexual function. This results in considerable underdiagnosis because patients are often reluctant or embarrassed to initiate discussion of these issues themselves. By not recognizing sexual dysfunction as a common organic sequel-lae of diabetes that should be addressed and treated, providers are missing an important opportunity to improve their patients' daily existence and quality of life.
Crossref | PubMed | Scopus (539) | Google ScholarSee all References Possible etiologies for ED secondary to hypertension include vascular damage due to hypertensive changes as well as hormonal abnormalities such as elevated prolactin levels.30x30Jaffe, A, Chen, Y, Kisch, ES, Fischel, B, Alon, M, and Stern, N. Erectile dysfunction in hypertensive subjects: assessment of potential determinants. Hypertension. 1996; 28: 859–862
However, sildenafil should be used carefully with nitrates because their combination can result in severe hypotension and death.68 Both short- and long-acting nitrates are commonly prescribed to treat angina, but they have no prognostic benefit. In addition, there are numerous alternatives to treat angina, such as ranolazine and ivabradine, which do not interact with PDE5 inhibitors. As a result, patients with ED wishing to take PDE5 inhibitors can safely discontinue their nitrates and replace this treatment with the other anti-anginal agents.68
Abnormalities in the vascular, neural, endocrine, muscular, or psychiatric systems can result in ED.2,3 EDDM is due to multisystemic disease. Atrophy or apoptosis of cavernosal smooth muscle can occur due to loss of Bcl-2 expression in cavernosal smooth muscle and lead to ED. Abnormal amounts of advanced glycation end products is a common occurrence. These chemicals may have an effect on potassium channels that facilitate intracellular calcium release and subsequent cavernosal smooth muscle relaxation. Connective tissue synthesis is increased due to transforming growth factor-beta. The decrease in smooth muscle and the increase in collagen decreases the compliance of the erectile tissue. Neuropathic damage to both the somatic and autonomic nerves has been clearly defined in DM. Partial occlusion of the pelvic or intracavernosal arteries, hypogonadotropic hypogonadism, and depression associated with a chronic illness (DM) can all play a primary or secondary role in the development of EDDM. On a molecular level, studies have demonstrated decreased levels of endothelial and neuronal nitric acid synthase (NS) and decreased cavernosal artery and sinusoidal response to nitric oxide. Abnormalities in nitric oxide rapidly render the functional syncytium of the corpora cavernosa unable to synchronously relax. As the patient with diabetes ages, the concentration of constrictors, including endothelin, prostanoids, and possibly angiotensin, increases as the production of the relaxants, including nitric oxide, vasointestinal peptide, and prostacyclin, decreases.
Yes, and there’s the rub. High blood pressure, especially if untreated, can lead to erectile dysfunction (ED). So can medications your doctor prescribes to bring down your high blood pressure. Fortunately, not all meds cause ED. Thiazides, diuretics or “water pills,” are common ED culprits. So are beta blockers. These effective heart meds slow your system down, and also affect blood flow where you need it -- in your penis -- at the right time. Alpha blockers, another class of medications that lower high blood pressure, are less likely to cause ED. So talk with your good doc about medication choices and side effects, so you can choose the right med for you.
Normal penile erection is controlled by two mechanisms: reflex erection and psychogenic erection. Reflex erection occurs by directly touching the shaft of the penis, while psychogenic erection occurs by erotic or emotional stimuli. ED is a condition where erection does not take place by either mechanism. ED can occur because of hormonal imbalance, neural disorders or lack of adequate blood supply to the penis.54 Lack of blood supply can be a result of impaired endothelial function associated with CAD.54

Crossref | PubMed | Scopus (35) | Google ScholarSee all References Also, if lower blood pressure level was the primary etiology of ED, all classes of antihypertensive agents should be expected to have relatively similar effects on erectile function because of their efficacy in lowering pressure, which has not been seen.6x6Kloner, RA. Erectile dysfunction and cardiovascular risk factors. Hosp Pract (Off Ed). 2001; 36: 41–44 (49-51.)
The study, which retrospectively tracked more than 43,000 men for an average of 3.3 years, found that men prescribed phosphodiesterase-5 (PDE5) inhibitors—the type of erectile dysfunction drug sold under the names Viagra, Levitra, Cialis and others—after their first heart attack were 38 percent less likely to die from any cause. No survival benefit was seen among men taking alprostadil, another type of erectile dysfunction drug that works through a different mechanism.
No matter what the cause of erectile dysfunction, it is likely to cause feelings of stress and other emotional reactions. It’s also not uncommon for erection problems to cause tension in a relationship, particularly if one or both partners withdraws emotionally and the problem is not talked about. And it’s possible for a man’s renewed ability to have intercourse after a period of no sexual activity to stir up relationship issues.
×