Penile Injections for erectile dysfunction treatment
Here’s another treatment for erectile dysfunction.
Prior to the advent of intracorporeal pharmacotherapy, or penile injections, penile prosthesis was the only thing other than drug therapy really available. The advent of penile injections began when a scientist working with dogs found that papaverine injected into the penis produced an erection.
The initial drug was papaverine, and this was then mixed with a drug called phentolamine.
Papaverine injections for ed
Papaverine was originally marketed for use in vascular surgery to dilate vessels and additionally was taken as an oral medication to act as a vaso dilator in people with lower extremity ischemia and people with vascular diseases of the legs. The off-label indication was used extensively throughout the 1980s. More papaverine was sold in the first year that this usage was discovered than had been sold in the prior thirty years.
Prostaglandin injections for ed
Alprostadil, which was the manufactured version of prostaglandin E-1, proved to be effective as well. This drug caused relaxation of the corporal smooth muscle and produced an erection. It could be tolerated well and was sold for use in babies with heart abnormalities. The vials of alprostadil came in a highly concentrated form and were then diluted for use as penile injections.
Prostaglandin by itself had a fairly high response rate, but when mixed with phentolamine and papaverine, its effectiveness was greatly increased.
In 1995, the Upjohn Company had alprostadil powder approved for use as a penile injection. The product, known as Caverject, comes as a dry powder and liquid is added to it at the time of use. It originally came in 10- and 20-mcg vials.
Prior to the advent of these FDA-approved standardized dosage regimens, prostaglandin came in a diluted fashion, typically using up to 10 to 20 mcg per cc. Prostaglandin alone achieved a poor clinical response so Regitine was added (termed bi-mix). If this continued to fail, a third medication called phentolamine, termed tri-mix, was added. While each of these medications is FDA approved for different uses, their use either singly or in combination was not, so it was important to notify patients that these drugs were being used in an off-label manner.
I generally reserve the more exotic mixtures when the standard regimen fails. Some have advocated the use of an additional drug atropine, which can speed up the heart rate and also improve erections as well.
B.F. was a sixty-five-year-old with erectile dysfunction. He had long-standing diabetes and had been recommended to use penile injections. He came to the emergency room with priapism because he had an erection for more than twelve hours. He had given himself six injections in the preceding twelve hours. These injections were all unrelated to each other, and they were with six different partners. We were able to reduce the erection with irrigation of the penis with drugs to reduce the priapism.
Consent should always be obtained prior to an injection program to clearly document that this procedure is not without risks.
I always start penile injection therapy in the office with careful instructions and closely follow the patient.
There are minimal contraindications to treatment with pharmacological intercavernosal injections.
How often are ed shots performed?
I usually recommend using the injections no more than three times per week. Although patients have used them two or three times per day, I do not recommend this. I also do not recommend an additional injection if the first response is not complete. It is extremely important not to share this medication with your friends as this has happened on occasion.
Ed injections side effects
Very few patients drop out of a pharmocologic erection program because of pain. A few men feel that the pain is disabling to their erections, so I recommend taking two extra-strength Tylenol tablets one hour before anticipated injection and relations.
This generally works well. We are not sure why men develop pain, although it tends to be more common with prostaglandin than with the other agents.
The most dreaded complication of intracorporal penile injections is a prolonged erection and priapism. Prolonged erections and priapism can result from any single drug or any combination of drugs.
Any erection greater than two hours duration is defined as prolonged, and priapism is when an erection lasts longer than four hours. There is no absolute definition of a prolonged erection or priapism, but any man who has used a penile injection and has an erection that lasts for more than two hours should consider immediate medical attention.
After a period of two hours, the penis begins to develop a low oxygen state and can begin to develop scarring and ultimately the loss of corporal smooth muscle.
B.C. was a fifty-one-year-old man who was on a stable course of prostaglandin injections for his erectile dysfunction. It worked quite well for him, but another man, his friend, came to the emergency room with priapism. On careful questioning, it turned out that B.C. had given him the injections as well as instruction. Although this man had no erectile dysfunction, he thought it would augment his functioning and used the injection. This resulted in priapism for more than six hours.
Prolonged erection after ed injections
I instruct all my patients to have pseudoephedrine on hand and to take a single tablet if their erection isn’t gone within an hour. If this is unsuccessful, terbutaline, a drug used for the treatment of asthma has been successful in abating most prolonged erections.
However, if a man truly begins to develop priapism, it is important to get treatment within three to four hours. The first treatment option is to irrigate the penis and aspirate the old blood out. Simply removing the blood and oxygenating the tissues with fresh blood is sometimes all that is necessary. If, however, it is a fairly resistant erection and returns, I then use a mixture of phenylephrine.
Blood pressure and heart rate must be carefully monitored as cases of cardiac problems have been related to these medications as well.
One of the benefits of intracavernosal injections is an overall improvement in erections. Many men report that their erections are actually better for several episodes of intercourse after a single penile injection and, therefore, will tend to use it infrequently.