The first successful pharmacological treatment of erectile dysfunction was through penile injections of papaverine and phenoxybenzamine. To date, a number of medications have been used for this purpose, most commonly papaverine, phentolamine and alprostadil in isolation or as a mix for penis injection therapy.

Penile injections are administered by the patient himself just before sexual intercourse and they induce an erection within 5 minutes. The use of an injection mechanism similar to that for insulin injections makes administration easy and painless.

Penile injections do not require any sexual stimulation to work (this means that erections will be achieved irrespective of sexual desire) and their efficacy rate is significantly higher than PDE-5 inhibitors. More importantly, patients have consistently reported harder erections and overall higher sexual satisfaction from the use of penile ejections compared to PDE5 inhibitors. On the other hand, taking an oral pill as opposed to administering an injection before intercourse is more acceptable for most patients. In summary, the advantages and disadvantages of penile injections compared to PDE-5 inhibitors are the following:

Advantages of penile injections compared to PDE-5 inhibitors

• Significantly higher efficiency rates irrespective of sexual stimulation and desire (up to 93%)
• Faster action time
• Stronger and more rigid erections even after ejaculation (1-2 hours duration)
• No reported side effects

Disadvantages of penile injections compared to PDE-5 inhibitors

• Administration is less comfortable
• Rarely there may be increased chance of topical side effects such as priapism (prolonged erection lasting more than four hours)

The type and dosage of injection therapy that will result in maximum responses are patient specific and will thus need to be evaluated during a consultation with your doctor.