Currently, placement of a penile prosthesis is the most common surgical procedure performed for erectile dysfunction. Penile prosthesis placement is typically reserved for men who have tried and failed (either from efficacy or tolerability) or have contraindications to other forms of therapy including PDE5 inhibitors, intraurethral alprostadil, and injection therapy.
Stiffy Solution: Obviously, no one should ever go off a prescribed med without consulting with a doctor. But there are erection-friendly alternatives to nearly every daisy-wilting medicine listed above. And your dude shouldn't let embarrassment keep him from talking to his GP about this — doctors are well aware that erectile difficulties are a possible side effect for all of these medicines; they just don't know which patients will experience what side effects, so they're waiting for you, the patient, to bring it up.
Psychological factors — Psychological issues such as depression, anxiety, guilt or fear can sometimes cause sexual problems. At one time, these factors were thought to be the major cause of impotence. Doctors now know that physical factors cause impotence in most men with the problem. However, embarrassment or "performance anxiety" can make a physical problem worse.
Alteration of NO levels is the focus of several approaches to the treatment of ED. Inhibitors of phosphodiesterase, which primarily hydrolyze cGMP type 5, provided the basis for the development of the PDE5 inhibitors. Chen et al administered oral L-arginine and reported subjective improvement in 50 men with ED.  These supplements are readily available commercially. Reported adverse effects include nausea, diarrhea, headache, flushing, numbness, and hypotension.
The nerves and endothelium of sinusoids and vessels in the penis produce and release transmitters and modulators that control the contractile state of corporal smooth muscles. Although the membrane receptors play an important role, downstream signaling pathways are also important. The RhoA–Rho kinase pathway is involved in the regulation of cavernosal smooth muscle contraction. 
The most important organic causes of impotence are cardiovascular disease and diabetes, neurological problems (for example, trauma from prostatectomy surgery), hormonal insufficiencies (hypogonadism) and drug side effects. Psychological impotence is where erection or penetration fails due to thoughts or feelings (psychological reasons) rather than physical impossibility; this is somewhat less frequent but can often be helped. In psychological impotence, there is a strong response to placebo treatment.
The cost to you for ED drug therapy varies considerably, depending on the pharmacy price, prescription co-pays, and your level of health plan coverage. Nationally, the out-of-pocket cost per pill ranges from approximately $15 to $20. Even if private insurance covers it, you may be limited to four doses per month. Here are a few things you can do to contain costs:
How soon the drugs start working ranges from 15 to 60 minutes. Neither Viagra nor Levitra will work if you take them after a meal, which blocks their absorption. However, neither Cialis nor Stendra interact with food this way. The onset time determines how soon you can engage in intercourse. Stendra and daily-use Cialis are closest to being an "on demand" erectile drug; using the others requires more planning.
In the majority of patients the impotence is organic, though not endocrinologic, and there is no easily remedied cause. These patients require physiologic testing and urologic consultation for specific diagnosis. Likely causes of impotence in this group include vascular and neurologic diseases. These patients are candidates for penile prostheses or, in special cases, for revascularization. Patients interested in surgical approaches should be referred for further testing. There is little to be gained by continuing the work-up of patients who prefer not to have an operation.
There are treatments available to help you to get and maintain an erection. In addition, making healthy changes to your lifestyle could help with impotence. Switching to a healthier balanced diet, taking more exercise and cutting down on or giving up alcohol and cigarettes could help you to see an improvement in sexual function. If you think that the problem may be related to stress or anxiety, counselling can also help.
Sexual dysfunction and ED become more common as men age. The percentage of complete ED increases from 5% to 15% as age increases from 40 to 70 years. But this does not mean growing older is the end of your sex life. ED can be treated at any age. Also, ED may be more common in Hispanic men and in those with a history of diabetes, obesity, smoking, and hypertension. Research shows that African-American men sought medical care for ED twice the rate of other racial groups.