Alprostadil should not be used in men at higher risk for priapism (erection lasting longer than six hours) including men with sickle cell anemia, thrombocytopenia (low platelet count), polycythemia (increased red blood cell count), multiple myeloma (a cancer of the white blood cells), and is contraindicated in men prone to venous thrombosis (blood clots in the veins) or hyperviscosity syndrome who are at increased risk for priapism.
If you just got off solo, you might have to wait before you can hop into bed with your partner, says Dr. Brahmbhatt. It might have something to do with a spike in the hormone prolactin after you orgasm, according to a study published in the International Journal of Impotence Research. This hormone has been linked to difficulties maintaining an erection or even ejaculating.
While we may think the penis has a mind of it’s own, it’s actually heavily dependent to the brain, and too much stress can interfere with a man’s ability to obtain and hold an erection. According to Healthline, stress can interrupt how your brain sends messages to the penis to allow extra blood flow. Even though a man may want to have sex, too much stress can make this impossible.
PDE 5 inhibitors are broken down primarily by enzyme, cytochrome P450enzyme CYP3A4. Medications that decrease or increase the activity of CYP3A4 may affect levels and effectiveness of PDE 5 inhibitors. Such drugs include medications for the treatment of HIV (protease inhibitors) and the antifungal medications ketoconazole and itraconazole. Thus caution is recommended.
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.
The association between low testosterone and ED is not entirely clear. Although these 2 processes certainly overlap in some instances, they are distinct entities. Some 2-21% of men have both hypogonadism and ED; however, it is unclear to what degree treating the former will improve erectile function.  About 35-40% of men with low testosterone see an improvement in their erections with testosterone replacement; however, almost 65% of these men see no improvement. 
2 inability of the adult male to achieve or sustain a penile erection or, less commonly, to ejaculate after achieving an erection. Several forms are recognized. Functional impotence has a psychological basis. Organic impotence includes vasculogenic, neurogenic, endocrinic, and anatomical factors. Anatomical impotence results from physically defective genitalia. Atonic impotence involves disturbed neuromuscular function. Poor health, old or advancing age, drugs, smoking, trauma, and fatigue can induce impotence. Also called erectile dysfunction, impotency. impotent, adj.
Erectile dysfunction (ED), also known as impotence, is the inability to achieve or sustain a hard enough erection for satisfactory completion of sexual activity. Erectile dysfunction is different from other health conditions that interfere with male sexual function, such as lack of sexual desire (decreased libido) and problems with ejaculation release of the fluid from the penis (ejaculatory dysfunction) and orgasm/climax (orgasmic dysfunction), and penile curvature (Peyronie's disease), although these problems may also be present. ED affects about 50% of men age 40 and over. This article focuses on the evaluation and treatment of erectile dysfunction.
The mechanisms by which testosterone plays a role in erectile function are not completely understood. A study evaluating the effect of testosterone on erections in surgically castrated rabbits and control animals, in which the rabbits’ intracavernosal pressures were compared after cavernosal nerve stimulation, determined that castrated rabbits had much lower pressures after stimulation than control rabbits did.  Notably, the pressures increased when castrated rabbits received exogenous testosterone replacement.
I am 60 & have erection problems for 20 plus years. Factors for me include heavy smoking for 30 years, overweight, bad eating habits,many medications that claim " may cause sexual side effects ", extreme anxiety, circumcision, & stressful relationships. E.D. has been a big part of relationships ending. Masturbation is now my only recourse & that is many times unsuccessful Also have tried all of the E.D. medications with no success.Stress has been the biggest factor for inability to achieve an erection for me. An inventory of male erogenous zones is key. Many males are shy about trying what works for me with is extreme nipple play. That allows orgasm for me 90 percent of the time. Even at my age daily orgasms are welcome in me life. As far as knowing how to care for the older ladies, it is a learning process as to which I have been a good student. Pleasing a lady even without intercourse is very much possible.
But the main challenge to finding the best ED drug for you may turn out to be health insurance rules—not biochemistry. It's a common practice among insurers to limit the number of pills you can obtain per month. After you hit your limit, the out-of-pocket cost for a single pill can be as high as $20. "The main obstacle in my practice is the cost," Dr. Liou says. You'll need to work with your doctor to get the pill you need at a price you can afford.
Malleable implants usually consist of paired rods, inserted surgically into each of the corpora cavernosa. The rods are stiff, and to have an erection, one bends them up and then when finished with intercourse one bends them down. They do not change in length or width. The malleable implants are the least mechanical and thus have the lowest risk of malfunction. However, also have the least "normal appearance."
Vacuum constriction devices may be effective at generating and maintaining erections in many patients with erectile dysfunction and these appear to have a low incidence of side effects. As with intracavernosal injection therapy, there is a significant rate of patient dropout with these devices, and the reasons for this phenomenon are unclear. The devices are difficult for some patients to use, and this is especially so in those with impaired manual dexterity. Also, these devices may impair ejaculation, which can then cause some discomfort. Patients and their partners sometimes are bothered by the lack of spontaneity in sexual relations that may occur with this procedure. The patient is sometimes also bothered by the general discomfort that can occur while using these devices. Partner involvement in training with these devices may be important for successful outcome, especially in regard to establishing a mutually satisfying level of sexual activity.
early 15c., "physical weakness," also "poverty," from Middle French impotence "weakness," from Latin impotentia "lack of control or power," from impotentem (nominative impotens); see impotent. In reference to a want of (male) sexual potency, from c.1500. The figurative senses of the word in Latin were "violence, fury, unbridled passion." Related: Impotency.
Currently, there are no therapies that cure erectile dysfunction. However, a number of effective therapies are available that allow an individual to have an erection when desired. Depending on the cause of the erectile dysfunction, certain therapies may be more effective than others. Although there is limited data on lifestyle modification, intuitively, decreasing risk factors for erectile dysfunction may help prevent progression of disease.
For the patient whose history suggests organic impotence, further history, physical and laboratory data will help identify the cause. The classification listed in Table 187.2 is based on the pathophysiologic scheme presented above, and includes mechanical problems that can interfere with erection. Vascular disease is the most common cause of impotence. In advanced cases, Lehriche's syndrome of aortoiliac occlusion will be suggested by bilateral thigh or calf claudication, loss of muscle mass in the buttocks and legs, and impotence. However, the majority of patients with vascular impotence have less severe vascular disease and many will have occlusive disease of the hypogastric-cavernous bed only. Even among patients without claudication, vascular disease is still a likely cause of impotence, especially if risk factors for atherosclerosis are present. Nonatherosclerotic disease is a consideration in the patient with a history of trauma or radiation to the pelvis, both of which cause fibrosis of vessels.
Erectile dysfunction is often assumed to be a natural concomitant of the aging process, to be tolerated along with other conditions associated with aging. This assumption may not be entirely correct. For the elderly and for others, erectile dysfunction may occur as a consequence of specific illnesses or of medical treatment for certain illnesses, resulting in fear, loss of image and self-confidence, and depression.
The 4 ED medicines we prescribe – Generic sildenafil 20 mg, Viagra (also sildenafil), Cialis (Tadalafil), or Levitra (Vardenafil) - are generally safe but shouldn’t be used as recreational drugs. They’re meant to treat a medical condition and can cause serious side effects including but not limited to an erection lasting more than four hours, sudden loss of vision in one or both eyes, and sudden decrease or loss of hearing.
In their extensive review, Bassil and coworkers summarise the benefits and risks, with benefits such as improvement of sexual function, bone density, muscle strength, cognition and overall improvement in quality of life. Among the risks that have been suggested include erythrocytosis, liver toxicity, worsening of sleep apnoea and cardiac function, possibly increasing symptoms of benign prostatic hyperplasia (BPH). They also note that although a possibility of stimulation of prostate cancer has been hypothesised, no scientific or clinical evidence exists to this possible risk.38
ED usually has something physical behind it, particularly in older men. But psychological factors can be a factor in many cases of ED. Experts say stress, depression, poor self-esteem, and performance anxiety can short-circuit the process that leads to an erection. These factors can also make the problem worse in men whose ED stems from something physical.