Dosage and self-injection technique for alprostadil

When starting treatment with alprostadil, dose titration is needed to determine the optimal dose (ie the minimum dose that produces an adequate erection lasting no more than 60 minutes). The time to onset of effect is 5 to 20 minutes, and the duration is dose-dependent. The first dose of alprostadil should be administered by an experienced practitioner; following supervised training in self-administration (see Self-injection technique for intracavernosal alprostadil), most people can inject themselves at home.

In males with idiopathic, neurogenic or psychogenic erectile dysfunction, use:

alprostadil 2.5 micrograms intracavernosally, initially. Increase each subsequent dose by 2.5 micrograms until an adequate erection is achieved (maximum dose 60 micrograms). Do not inject more than once in 24 hours and no more than 3 times per week. erectile dysfunction alprostadil

In males with a vascular or other organic cause of erectile dysfunction, use:

alprostadil 5 micrograms intracavernosally, initially. Increase each subsequent dose by 5 micrograms until an adequate erection is achieved (maximum dose 60 micrograms). Do not inject more than once in 24 hours and no more than 3 times per week. alprostadil

Continuation rates on intracavernosal self-injection programs are approximately 50% within 6 to 24 months of starting treatment.

Figure 1. Self-injection technique for intracavernosal alprostadil

This technique delivers the drug to one of the corpus cavernosa, avoiding the neurovascular bundle on the dorsum of the penis.

The penis is held and extended with the non-injecting hand, and the penile shaft is steadied against the thigh.

The optimal sites for injection are between the 8 and 10 o’clock, or the 2 and 4 o’clock, positions of the shaft cross-section. Subcutaneous veins and the urethra should be avoided.

Drawing back on the needle is important, to ensure it has not entered a blood vessel; a small drop of blood is usually consistent with entry into the corpus.

The drug should be injected slowly using a fine 25G needle, holding the syringe perpendicular to the skin.