See also: Muse ® Alprostadil transurethral route
What it is and why it is used
Alprostadil (Trade name Caverject ®) is a vasodilator drug used in the treatment of erectile dysfunction (difficulty in achieving and / or maintaining a satisfactory erection). For this purpose, it is injected directly into the corpora cavernosa of the penis, resulting in erections valid as needed even in patients with severely compromised circulation or with alterations of the nervous system.
In myelolysis, the positive response rate (in terms of satisfactory erection) to the use of alprostadil appears higher than that induced by oral sildenafil (Viagra ®); however, the lower the practicality of use and the greater the risks of local complications and psychological side effects.
View the package insert of alprostadil (Caverject ®)
Unlike viagra, alprostadil supports the mechanism of physiological erection even in the absence of sexual stimulation. The action begins about 5-20 minutes after the injection and lasts for about an hour, often even after ejaculation.
The use of alprostadil in intraurethral suppositories (small tablets, the size of half a grain of rice, to be inserted into the urethra with a special applicator), instead of direct injection at the base of the penis, produces a much lower action than the injectable formulation, resulting in effective in producing a satisfactory erection in only 30-40% of patients with erectile dysfunction (instead of 80% and above).
How it works
Alprostadil is able to induce erection by direct release of smooth muscle; in this sense, it shares the same action as phentolamine and papaverine, an alkaloid extracted from opium but without narcotic effects. Often the two substances are combined together in pharmaceutical specialties.
Aprostadil is a synthetic analogue of prostaglandin 1 (PGE1), a substance with marked vasodilatory properties.
Method of use and side effects
The drug is injected at the base of the penis a few minutes before sexual intercourse.
The generally recommended maximum frequency of administration should not exceed one injection per day and three per week, with at least a 24 hour interval between each administration.
Locally, the injection of alprostadil (Caverject ®) can produce mild to moderate pain in the penis, prolonged erections (lasting 4-6 hours), bleeding and priapism. The usual range of injection is 5-20 µg of alprostadil, up to a maximum of 60 µg.
We normally start with a dose of a few µg and evaluate the result in terms of rigidity and penetrative capacity with the doctor; obviously, before performing the alprostadil injections independently, a learning training and a preventive andrological examination is necessary.
