Individuals at higher risk for priapism (painful 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 history of blood clots (for example, deep venous thrombosis [DVT]) or hyperviscosity (thick blood) syndrome are at increased risk for priapism with MUSE.
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.
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.
Vascular damage may result from radiation therapy to the pelvis and prostate in the treatment of prostate cancer.  Both the blood vessels and the nerves to the penis may be affected. Radiation damage to the crura of the penis, which are highly susceptible to radiation damage, can induce ED. Data indicate that 50% of men undergoing radiation therapy lose erectile function within 5 years after completing therapy; fortunately, some respond to one of the PDE5 inhibitors.
Counselling and psychotherapy can help if one of the underlying causes of your erectile dysfunction is psychological. Counselling can also benefit men who have lost sexual confidence, even though their erectile dysfunction is caused by physical factors. Counselling may be provided by your doctor, a psychologist or a psychiatrist. Your partner may also be involved.
Metabolism (breakdown) of vardenafil can be slowed by aging, liver disease, and concurrent use of certain medications (such as erythromycin [an antibiotic], ketoconazole [Nizoral, a medication for fungal/yeast infections], and protease inhibitors [medications used to treat AIDS]). Slowed breakdown allows vardenafil to accumulate in the body and potentially increase the risk for side effects. Therefore, in men over 65 years of age with liver disease, or who are also taking medication(s) that can slow the breakdown of vardenafil, the doctor will initiate vardenafil at low doses to avoid its accumulation. For example,
If you can't take one of these oral medications, your physician may have you try Caverject (alprostadil for injection), a hormone that you inject into your penis using a fine needle, or Muse (alprostadil urogenital), a tiny suppository that you insert into the tip of the penis. Both of these will bring on an erection within five to 15 minutes without sexual stimulation.
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.
I think that a very powerful argument to young men who want to perform at the highest level is to point out the destructive nature of what they’re doing. If they’re having 18 drinks per week, if they’re having three, four, five drinks at any one time, they’re going to guarantee that their erections are not going to be at the highest level. I can’t tell you the number of men who come in saying, they went out, they had a date, they had a big dinner– which, by the way, is also not a great thing for erections, because all the blood is now going to your gut instead of to the genital area. And how important lifestyle changes are to improving your performance, as well, if not better, than the medications. So make certain that you exercise modestly, not excessively. Make certain that you have a smaller meal on an evening or a day that you want to have a sexual encounter, because you want the blood to go, once again, to the penile area and not to your gut. And really, the whole idea of stress– if you’re stressed out, if you’re worried about a lot of things, if you’re distracted, you can’t initiate that psychic stimulus to your spinal cord and then ultimately to your penis. So stress management is incredibly important.
Somatomotor penile innervation originates in Onuf’s nucleus in the S2-4 spinal segments. These nerves travel to the ischiocavernosus and bulbocavernosus muscles when activated lead to contraction necessary for the rigid-erection phase. Several animal studies show that stimulation of the somatomotor pathways may also be under sympathetic control, and adrenergic stimulation may lead to contraction of these muscles during ejaculation (13,14). Somatomotor spinal reflexes may also be initiated by genital stimulation. For instance, the well-known bulbocavernosus reflex is evidence this reflex exists; however the clinical significance of its absence in the neurological assessment of ED has not been substantiated (15).
When sexually stimulated there is a release of a chemical, nitric oxide (NO) in the blood vessels of the corpus cavernosum. The NO stimulates the production of a compound called cGMP, which causes relaxation of the smooth muscle in the blood vessels supplying the corpus cavernosum. PDE 5 is an enzyme that breaks down cGMP. By inhibiting the breakdown of cGMP by PDE5, these medications allow cGMP to build up in the penis. cGMP causes muscles in the corpora cavernosa of the penis to relax. When the muscle is relaxed, more blood can flow into the penis and fill the spaces in the penis. As the penis fills with blood, the veins in the penis are compressed, and this results a hard erection. When the effect on PDE5 decreases, the cGMP levels go down and the muscle in the penis contracts, causing less blood to flow into the penis and allowing the veins to open up and drain blood out of the penis.
In order to establish whether normal erections are occurring overnight (nocturnal erections), the doctor may organise nocturnal penile tumescence (NPT) testing. This involves wearing a monitor overnight in your own home. The data from this monitor is then assessed to analyse how often erections occurred, how long they lasted, and how rigid and large the penis was during the erections. If NPT testing is normal, the cause of erectile dysfunction is usually psychological. If not, further testing of the blood flow in the genital area may be required to see if there is blockage or leakage. The doctor may also organise a blood test of levels of hormones such as testosterone, prolactin and thyroid stimulating hormone to see if these are contributing to the erectile dysfunction.
The laboratory results should be discussed with the patient and, if possible, with his sexual partner. This educational process allows a review of the basic aspects of the anatomy and physiology of the sexual response and an explanation of the possible etiology and associated risk factors (eg, smoking and the use of various medications). Treatment options and their benefits and risks should be discussed. This type of dialogue allows the patient and physician to cooperate in developing an optimal management strategy.
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.
Certain types of blood pressure medications, antiulcer drugs, antihistamines, tranquilizers (especially before intercourse), antifungals (hetoconazole), antipsychotics, antianxiety drugs, and antidepressants, known as selective serotonin reuptake inhibitors (SSRIs, including Prozac and Paxil), can interfere with erectile function. Smoking, excessive alcohol consumption, and illicit drug use may also contribute. In rare cases, low levels of the male hormone testosterone may contribute to erectile failure. Finally, psychological factors, such as stress, guilt, or anxiety, may also play a role, even when the impotence is primarily due to organic causes.
Sexual stimulation causes the release of neurotransmitters from cavernosal nerve endings and relaxation factors from endothelial cells lining the sinusoids. NOS produces NO from L-arginine, and this, in turn, produces other muscle-relaxing chemicals, such as cGMP and cyclic adenosine monophosphate (cAMP), which work via calcium channel and protein kinase mechanisms (see the image below). This results in the relaxation of smooth muscle in the arteries and arterioles that supply the erectile tissue, producing a dramatic increase in penile blood flow.
A common and important cause of ED is vasculogenic. Many men with ED have comorbid conditions such as hyperlipidemia, hypercholesterolemia, tobacco abuse, diabetes mellitus, or coronary artery disease (CAD).  The Princeton III Consensus recommends screening men who present with ED for cardiovascular risk factors; ED may be the earliest presentation of atherosclerosis and vascular disease. 
In some cases, nocturnal penile tumescence testing is performed to find out whether the man has erections while asleep. Healthy men usually have about four or five erections throughout the night. The man applies a device to the penis called a Rigiscan before going to bed at night, and the device can determine whether he has had erections. (If a man is able to have normal erections at night, this suggests a psychological cause for his impotence.)
Their treatment plan will include a great deal of information about ED. It is important you take the time to read it all. You will be better prepared to manage your condition as a partner—and not just a patient. Also, erectile dysfunction is often a symptom of a more serious underlying condition—like heart disease, diabetes, high blood pressure, or even depression. That’s why we want you to learn as much as you can. Nothing would be a sign of our success more so then if you could resolve the condition that causes your ED instead of needing to use the medications your doctor prescribes. We strongly recommend optional laboratory tests. You do not need to get them to receive treatment but it can be one of the best things you can do for your health in the long run.
The idea of using low-energy shock waves to treat erectile dysfunction comes from studies that show that these types of shocks help heart blood vessels regrow, a process called revascularization. Shock wave therapy may also work on the penis, and there have been some promising results, but it’s not currently an approved ED treatment. "It’s similar to the type of shock waves used to break up kidney stones, and it may cause revascularization,” says Bennett. “However, there are not yet any good controlled studies to recommend it to patients."
It is common for a healthy older man to still want sex and be able to have sex within appropriate limitations. Understanding what is normal in older age is important to avoid frustration and concern. Older men and their partners often value being able to continue sexual activity and there is no age where the man is ‘too old’ to think about getting help with his erection or other sexual problems.
This is one of many types of constricting devices placed at the base of the penis to diminish venous outflow and improve the quality and duration of the erection. This is particularly useful in men who have a venous leak and are only able to obtain partial erections that they are unable to maintain. These constricting devices may be used in conjunction with oral agents, injection therapy, and vacuum devices.
Following a detailed discussion about the history of erectile dysfunction and its risk factors, your doctor will examine the testicles and penis to help determine the cause of erectile dysfunction. Your doctor will check reflexes and pulses in the area to see if problems with blood vessels or nerves are contributing to the erectile dysfunction. If necessary, your doctor will order tests to help diagnose erectile dysfunction.
Yohimbine: The main component of an African tree bark, yohimbine is probably one of the most problematic of all natural remedies for ED. Some research suggests that yohimbine can improve a type of sexual dysfunction that is linked with a drug used to treat depression. However, studies have linked yohimbine to a number of side effects, which can include anxiety, increased blood pressure, and a fast, irregular heartbeat. Like all natural remedies, yohimbine should only be used after advice and under supervision from a doctor.
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.
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
The main surgical treatment of ED involves insertion of a penile implant (also called penile prostheses). Because penile vascular surgery is not recommended for aging males who have failed oral PDE5 inhibitors, ICI or IU therapies, implants are the next step for these patients. Although placement of a penile implant is a surgery which carries risks, they have the highest rates of success and satisfaction among ED treatment options.