See also: Muse ® Alprostadil transurethral
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 reaching and / or maintaining a satisfactory erection). For this purpose, it is injected directly into the corpus cavernosum of the penis, determining erections valid for the need even in patients with severely compromised circulation or with alterations of the nervous system.
In myelolesis patients, the rate of positive response (in terms of satisfactory erection) to the use of alprostadil appears to be higher than that induced by sildenafil (Viagra ®) orally; however, there is less practicality and greater risks of local complications and psychological side effects.
View the alprostadil package insert (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 is maintained 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), rather than by 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 an erection by direct release of smooth muscles; in this sense, it shares the same action as phentolamine and papaverine, an alkaloid extracted from opium but with no narcotic effects. Often the two substances are combined together in pharmaceutical specialties.
Aprostadil is a synthetic analogue of prostaglandin 1 (PGE1), a substance endowed with marked vasodilatory properties.
Mode 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 24 hours between one administration and another.
Locally, the injection of alprostadil (Caverject ®) can produce mild or moderate penile pain, prolonged erections (lasting 4-6 hours), bleeding and priapism. The usual injection range is 5-20 µg alprostadil, up to a maximum of 60 µg.
It normally starts with a dose of a few µg and the result is evaluated in terms of rigidity and penetrative capacity with the doctor; obviously, before making the alprostadil injections independently, a learning training and a preventive andrological visit are necessary.
