The FDA recommends that men follow general precautions before taking a medication for ED. Men who are taking medications that contain nitrates, such as nitroglycerin, should NOT use these medications. Taking nitrates with one of these medications can lower blood pressure too much. In addition, men who take tadalafil or vardenfil should use alpha blockers with care and only as instructed by their physician, as they could result in hypotension (abnormally low blood pressure). Experts recommend that men have a complete medical history and physical examination to determine the cause of ED. Men should tell their doctor about all the medications they are taking, including over-the-counter medications.
VED involved placing the penis in a clear plastic tube where negative pressure created by the vacuum pump leads to penile engorgement and tumescence. Usually a constriction ring can be placed on the base of penis following penile engorgement. Some men complain of bruising, a “cold” penis and pain associated with the constriction ring; however, in some men with NED sensation may not be intact mitigating the side effects of VEDs. VEDs have reported effectiveness up to 90% in certain ED populations and it remains a non-invasive means to achieve and erection.
Oral therapies via the PDE5i sildenafil, vardenafil, and tadalafil have been proven to be generally safe and effective in select NED populations. The majority of the treatment effectiveness data has been generated in the SCI population. Data regarding the use of PDE5i outside of the SCI population is lacking (58). Furthermore, the ED that exists in the population with neurologic disorders is often multifactorial and may be caused by psychogenic, psychosocial, hormonal, medication-related and disability-related factors. A careful evaluation of each patient must be performed to isolate these factors prior to initiating vasoactive therapy.
An occasional problem achieving an erection is nothing to worry about. But failure to do so more than 50% of the time at any age may indicate a condition that needs treatment. About 40% of men in their 40s report at least occasional problems getting and maintaining erections. So do more than half (52%) of men aged 40 to 70, and about 70% of men in their 70s.
However, a review of a United Kingdom medical record database found no evidence that the use of 5-alpha reductase inhibitors independently increase the risk for ED. In 71,849 men with benign prostatic hyperplasia (BPH), the risk of ED was not increased with the use of finasteride or dutasteride only (odds ratio [OR] 0.94), or a 5-alpha reductase inhibitor plus an alpha blocker (OR 0.92) compared with an alpha blocker only. In addition, the risk of ED was not increase in 12 346 men prescribed finasteride 1 mg for alopecia, compared with unexposed men with alopecia (OR 0.95). The risk of ED did increase with longer duration of BPH, regardless of drug exposure. 
There are many different treatment options for erectile dysfunction but your individual diagnosis will determine which treatment option is right for you. It is important to realize that not all treatment options will work for everyone. A doctor who has specialized in men’s sexual health (typically a urologist) will be the most qualified to discuss all of your treatment options with you. Many specialists will often encourage you to schedule additional follow up appointments to review how your treatment is working for you or if a different option may be more beneficial.
Side effects include lightheadedness, fainting, priapism, urethral bleeding (intraurethral), dyspareunia in the partner (intraurethral), hematoma (intracavernosal) or penile curvature secondary to scar (intracavernosal). Efficacy of intraurethral alprostadil has been demonstrated to be around 50% ("able to have intercourse") in randomized controlled trials.31,32 For intracorporeal injection, typically alprostadil is tried alone, or compounded with papaverine (nonspecific phosphodiesterase inhibitor that increases intracellular cyclic adenosine monophosphate and cGMP) and/or phentolamine (competitive, non-selective alpha1- and alpha2-adrenoreceptor blocker). Pinsky et al33 reported an extensive review of the benefits and drawbacks of the combinations of these drugs.
A cold slice of watermelon can do more than just satisfy thirst and hunger during the warm summer months; it can help with bedroom satisfaction. Citrulline, the amino acid found in high concentrations of watermelon, is found to improve blood flow to the penis. A 2011 study revealed men who suffered from mild to moderate ED and took L-citrulline supplementation showed an improvement with their erectile function and were very satisfied. Natural watermelon juice, or “nature’s Viagra,” can also be easier on the stomach, since taking pills like Viagra can cause nausea and diarrhea.
Clearly, PDE5i have revolutionized the treatment of ED in general and the neurogenic ED population is no exception. They remain safe and effective in most men with neurogenic ED; however, care must be taken in prescribing PDE5i to men high spinal cord lesions, MSA or possibly PD. VEDs are minimally-invasive and can be as effective as other modalities at leading to erection. However, high discontinuation rates are associated with VED use related to pain, difficulty using the device or cold penis. Intracavernosal therapy has been a mainstay of treatment for neurogenic ED and remains extremely successful in the SCI population. Trial of intracavernosal therapy for other causes of neurogenic ED can be considered second-line therapy, but there is a relative paucity of data for clinical outcomes related to its use outside of SCI men. Surgical therapy via penile implantation remains another second line approach and may also be utilized to assist men with bladder management. Higher complication rates of infections, and perforation have been reported compared to neurologically intact men. Many other compounds are currently being evaluated for the treatment of neurogenic ED as well as gene and stem cell therapy, but still should be considered investigational until substantiated by randomized controlled trials.
Melanocortin receptor agonists were found to induce erections serendipitously. A study investigating the dermatologic use of Melanotan-II (MT-II) was found to generate erections unexpectedly leading to the development of MTII derivatives for ED treatment (120). MT-II was initially used to induce pigment changes in the skin for artificial tanning but has been suspected to induce melanoma, however (121).
For best results, men with ED take these pills about an hour or two before having sex. The drugs require normal nerve function to the penis. PDE5 inhibitors improve on normal erectile responses helping blood flow into the penis. Use these drugs as directed. About 7 out of 10 men do well and have better erections. Response rates are lower for Diabetics and cancer patients.