Treatment. prostatitis or another acute infection affecting the genitalia can cause temporary impotence that clears up in response to antibiotics. The smooth muscle relaxant sildenafil (viagra) was introduced in 1998 as a treatment for organic impotence. Administration of testosterone may be indicated if low levels of this hormone are found in a blood sample. If impotence is organic and does not respond to other therapies, a penile prosthesis can be implanted; this is usually done surgically by a urologist. Other therapies include the use of vacuum tumescence devices and penile injection of pharmacologic agents that cause dilation.
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MUSE should not be used in men with a history of urethral stricture (narrowing of the tube in the penis that urine and semen pass through), inflammation or infection of the glans (tip) of the penis (balanitis), severe hypospadias (a condition where the opening of the urethra is not at the tip of the penis, rather on the underside of the penis), penile curvature (abnormal bend to the penis), and urethritis (inflammation/infection of the urethra).
Erections are neurovascular events, meaning that nerves and blood vessels (arteries and veins) are involved in the process of an erection and all must work properly to develop a hard erection that lasts long enough. Erection begins with sexual stimulation. Sexual stimulation can be tactile (for example, by a partner touching the penis or by masturbation) or mental (for example, by having sexual fantasies, viewing porn). Sexual stimulation or sexual arousal causes the nerves going to the penis to release a chemical, nitric oxide. Nitric oxide increases the production of another chemical, cyclic GMP (cGMP), in the muscle of the corpora cavernosa. The cGMP causes the muscles of the corpora cavernosa to relax, and this allows more blood to flow into the penis. The incoming blood fills the corpora cavernosa, making the penis expand.
Diabetes is a well-recognized risk factor for ED. A systematic review and meta-analysis found that the prevalence of ED was 37.5% in type 1 diabetes, 66.3% in type 2 diabetes, and 52.5% in diabetes overall—a rate approximately 3.5 times higher than that in controls. [39]  The etiology of ED in diabetic men probably involves both vascular and neurogenic mechanisms. Evidence indicates that establishing good glycemic control can minimize this risk.
No nitrate-based drugs should be given to men with suspected heart attacks if they have taken PDE5i medications within 24 hours. Combining PDE5i with nitrate-based medications can cause a severe and dramatic drop in blood pressure with potentially very dangerous consequences. This is also why someone should absolutely never share PDE5i medications with anyone else. If they happen to be taking one of the drugs that interacts dangerously with PDE5i medications, the results could be very serious. If there is any question about possible drug interactions, always check with a doctor or pharmacist.
Oral phosphodiesterase type 5 inhibitors (PDE5 inhibitors) unless contraindicated are the recommended first line medical therapy for erectile dysfunction. Currently, there are four different PDE5 inhibitors available. They all work the same way and have essentially the same results. They differ in how long they last in your body and in side effects.
The primary nerve fibers to the penis are from the dorsal nerve of the penis, a branch of the pudendal nerve. The cavernosal nerves are a part of the autonomic nervous system and incorporate both sympathetic and parasympathetic fibers. They travel posterolaterally along the prostate and enter the corpora cavernosa and corpus spongiosum to regulate blood flow during erection and detumescence. The dorsal somatic nerves are also branches of the pudendal nerves. They are primarily responsible for penile sensation. [10]
Patients should continue testosterone therapy only if there is improvement in the symptoms of hypogonadism and should be monitored regularly. You will need periodic blood tests for testosterone levels and blood tests to monitor your blood count and PSA. Testosterone therapy has health risks, and thus doctors should closely monitor its use. Testosterone therapy can worsen sleep apnea and congestive heart failure.
PDE5i for ED in patients with MS can be considered as reasonably effective and safe. Fowler et al. performed a randomized, multicenter, double-blind, flexible dose trial with open label extensions comparing sildenafil to placebo (75). A nearly 4-fold increase in effective erections was noted in the treatment arm, 96% vs. 24%. Sexual satisfaction and overall satisfaction were also improved in the treatment group based on IIEF scores, and quality of life assessments. Lombardi et al. evaluated tadalafil use in men with MS (71). Seventy eight percent of the men responded with improved erections, better quality of life with regards to sexual function, partner relationship and family life. Just less than half the men who responded to the tadalafil did so at the lower dosage of 10 mg. Subjects in either studies did not have any significant adverse side effects beyond flushing, and headache with PDE5i use.

Prior to starting with treatment of erectile dysfunction, it is important to make sure that it is safe from a medical standpoint to participate in sexual activity. Sexual activity is physical exertion, and in some men with significant heart disease, this increase in physical exertion can increase the risk of a heart attack. Thus, it is very important to discuss your cardiovascular risks with your doctor prior to trying any medication or treatment for erectile dysfunction.


Surgery: If neither drugs nor the vacuum pump works, your doctor may suggest surgery. With surgery, the doctor can place a device in your penis that will cause enough hardness for intercourse. In a few cases, infections may develop after the operation, and the doctor may have to remove the device. Another operation that may help you is rebuilding the blood vessels in the penis to increase blood flow into the penis or decrease blood flow out of the penis. These procedures can help you to get and maintain an erection.
What you need to know about delayed ejaculation Delayed ejaculation is a sexual disorder that can be distressing for a man and his partner and may disrupt a relationship. There are many reasons why delayed ejaculation occurs, including tissue damage, age, drugs, and the side effects of medication. They may be physiological or psychological. Find out how to get help. Read now
Alprostadil is a potent vasodilator and smooth muscle relaxant identical to the naturally occurring PGE1. PGE1 binds with specific receptors on smooth muscle cells and activates intracellular adenylate cyclase to produce cAMP, which in turn induces tissue relaxation through a second messenger system (96). PGE1 is the only FDA approved form of intracavernosal therapy and is available commercailly as EDEX, or Caverject. Its efficacy was demonstrated in several clinical trials where the rate of responders ranged from 40% to 80% (97,98). The most common adverse event is penile pain, which is not related to the injection of the medication itself. In men with prolonged use the pain is usually self-limited (99).
In the Massachusetts Male Aging Study (MMAS) among a community-based survey of men aged 40-70 years, 52% of the men reported some degree of erectile difficulty. Complete ED, defined as the total inability to obtain or maintain suitable erections during sexual stimulation, as well as the absence of nocturnal erections (normal erections [four to six/night], which occur during sleep), occurred in 10% of the men in the study. Lesser degrees of mild and moderate ED occurred in 17% and 25% of participants.
Besides PDE5 inhibitors and among second-line therapies are VCDs which are clear plastic chambers placed over the penis, tightened against the lower abdomen with a mechanism to create a vacuum inside the chamber. This directs blood into the penis. If an adequate erection occurs inside the chamber, the patient slips a small constriction band off the end of the VCD and onto the base of the penis. An erection beyond 30 min is not recommended. These devices can be a bit cumbersome, but are very safe.40
Ultimately, PDE5i have had a significant impact on the treatment of ED in men with SCI. The ease of use and tolerability of the medication has also led to improved satisfaction and quality of life that had been previously affected by SD. Head to head trials evaluating specific PDE5i within the SCI population are required to further elucidate drug preference. PDE5i should be considered first line therapy, however men with high thoracic and cervical lesions should be warned about an increased chance of dizziness with sildenafil and possibly other PDE5i use.
Treatment. prostatitis or another acute infection affecting the genitalia can cause temporary impotence that clears up in response to antibiotics. The smooth muscle relaxant sildenafil (viagra) was introduced in 1998 as a treatment for organic impotence. Administration of testosterone may be indicated if low levels of this hormone are found in a blood sample. If impotence is organic and does not respond to other therapies, a penile prosthesis can be implanted; this is usually done surgically by a urologist. Other therapies include the use of vacuum tumescence devices and penile injection of pharmacologic agents that cause dilation.

This penile tumescence monitor is placed at the base and near the corona of the penis. It is connected to a monitor that records a continuous graph depicting the force and duration of erections that occur during sleep. The monitor is strapped to the leg. The nocturnal penile tumescence test is conducted on several nights to obtain an accurate indication of erections that normally occur during the alpha phase of sleep.


Since endothelial dysfunction, CVD and ED are closely associated in epidemiological studies, the question for clinicians is whether to recommend the man presenting with ED undergo a cardiovascular (CV) evaluation. Clearly, based on numerous studies, ED can be considered at least a ‘marker’ for possible further vascular disease or CVD.15 In their report, Vlachopoulos and coworkers make the point that the man presenting with ED, the clinician, is offered an opportunity to attempt to improve the health of the man by addressing lifestyle modification, and consider further vascular evaluation owing to the clear relationship between endothelial dysfunction, ED and CVD.19
Psychotherapy, marital counseling, or sex therapy may be helpful in treating cases of impotence that have psychological or emotional causes. A range of other treatments exists for cases of impotence that arise from purely physiological causes. These treatments include vacuum devices, penile injections, and penile implants. These mechanical or physically invasive approaches have largely been superseded, however, by the drug sildenafil citrate (trade name Viagra), which is taken in pill form. This drug works by enhancing the effects of nitric oxide, a chemical that, upon sexual stimulation, is normally released to widen the blood vessels supplying the penis. The increased flow of blood through those vessels into certain tissues in the penis causes an erection. See also sexual dysfunction.
A vacuum erection device helps draw blood into the penis by applying negative pressure. This type of device is sometimes referred to as penis pump and may be used just prior to sexual intercourse. Several types of FDA approved vacuum therapy devices are available under prescription. When pharmacological methods fail, a purpose-designed external vacuum pump can be used to attain erection, with a separate compression ring fitted to the base of the penis to maintain it. These pumps should be distinguished from other penis pumps (supplied without compression rings) which, rather than being used for temporary treatment of impotence, are claimed to increase penis length if used frequently, or vibrate as an aid to masturbation. More drastically, inflatable or rigid penile implants may be fitted surgically.
Inside the cell, NOS catalyzes the oxidation of L-arginine to NO and L-citrulline. Endogenous blockers of this pathway have been identified. The gaseous NO that is produced acts as a neurotransmitter or paracrine messenger. Its biologic half-life is only 5 seconds. NO may act within the cell or diffuse and interact with nearby target cells. In the corpora cavernosa, NO activates guanylate cyclase, which in turn increases cyclic guanosine monophosphate (cGMP). Relaxation of vascular smooth muscles by cGMP leads to vasodilation and increased blood flow.
A study published in May 2014 in The Journal of Sexual Medicine found that some men can reverse erectile dysfunction with healthy lifestyle changes, such as exercise, weight loss, a varied diet, and good sleep. The Australian researchers also showed that even if erectile dysfunction medication is required, it's likely to be more effective if you implement these healthy lifestyle changes.
Other hormone levels: Measurement of other hormones beside testosterone (luteinizing hormone [LH], prolactin level, and cortisol level) may provide clues to other underlying causes of testosterone deficiency and erectile problems, such as pituitary disease or adrenal gland abnormalities. Doctors may check thyroid levels in some individuals as both hypothyroidism (low thyroid function) and hyperthyroidism (overactive thyroid function) can contribute to erectile dysfunction.
The first line and by far the most common treatment today is with the prescription drug sildenafil citrate, sold under the brand name Viagra. An estimated 20 million prescriptions for the pill have been filled since it was approved by the FDA in March 1998. It is also the most effective treatment with a success rate of more than 60%. The drug boosts levels of a substance called cyclic GMP, which is responsible for widening the blood vessels of the penis. In clinical studies, Viagra produced headaches in 16% of men who took it, and other side effects included flushing, indigestion, and stuffy nose.
Patient can inject medications directly into the corpora cavernosa to help attain and maintain erections. Medications such as papaverine hydrochloride, phentolamine, and prostaglandin E1 (alprostadil) can be used alone or in combinations to attain erections. All of these medications are vasodilators and work by increasing blood flow into the penis. Prostaglandin E1 (Caverject, Edex) is easier to obtain; however, it is associated with penile pain in some individuals. The use of combinations of two or three of these medications can decrease the risk of having penile pain.

The most common inflatable prosthesis is the three-piece penile prosthesis. It is composed of paired cylinders, which doctors surgically insert inside the penis. Patients can expand the cylinders using pressurized fluid (see figure 3). Tubes connect the cylinders to a fluid reservoir and pump, which doctors also surgically implant. The reservoir is usually in the pelvis. A doctor places the pump in the scrotum. By pressing on the pump, sterile fluid transfers from the reservoir into the cylinders in the penis. An erection is produced primarily by expansion of the width of the penis, however, one model can increase in length a small amount also. Lock-out valves in the tubing prevent the fluid from leaving the cylinder until a release valve is pressed. By pressing the relief valve and gently squeezing the penis, the fluid within the cylinders transfers back into the reservoir.


As with most other organ system in the human body, changes and loss of function is normal consequence of the ageing process. This is also true of the endocrine system, specifically the levels of testosterone production from the Leydig cells of the testicle. Accompanying the decrease in testosterone is a decrease in erections which also has a component in decrease in the blood supply to the penis making erection not as frequent and not as rigid compared with a young man’s erectile function. Although these changes are in itself not life threatening, they can impact a man’s relationship with his partner, and also ED may be a harbinger of other undiagnosed conditions such as coronary artery disease (CAD), hypercholesterolaemia or diabetes mellitus.6

Conditions associated with reduced nerve and endothelium function (eg, aging, hypertension, smoking, hypercholesterolemia, and diabetes) alter the balance between contraction and relaxation factors (see Pathophysiology). These conditions cause circulatory and structural changes in penile tissues, resulting in arterial insufficiency and defective smooth muscle relaxation. In some patients, sexual dysfunction may be the presenting symptom of these disorders.
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