Injections - Treating Erectile Dysfunction: Mens Sexual Health

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Injections

What if PDE5 inhibitors don't work for you? Many men who can't use these drugs or find them ineffective are able to get erections by injecting one or more prescription drugs into the side of the penis. The very idea may make you squeamish, and it's certainly not as easy as taking a pill. But the needle isn't very big (about half an inch long, the same size as those used to inject insulin), and drug injections can produce results.

Indeed, for men whose erectile dysfunction is caused by diabetes, injection therapy is more effective than Viagra. And it's the single most effective treatment available for men who experience the problem as a result of prostate surgery. Many men learn the technique quickly after a demonstration by a doctor or nurse in the doctor's office (see Figure 7).

Figure 7: Injection therapy This simple and highly effective method produces an erection within 5–20 minutes after a man injects medication into the base of the penis, causing the smooth muscle tissue of the penis to relax and allowing blood to flow into the corpora cavernosa.

There are several injectable drugs, all of which work by relaxing the smooth muscle tissue of the penis and allowing blood to flow into the corpora cavernosa. The only one specifically approved for erectile dysfunction is alprostadil (Caverject, Edex). However, a number of older drugs that were approved for other uses are also effective for erectile dysfunction. They are papaverine (Pavabid, Genabid, Pavatine, and others), phenoxybenzamine (Dibenzyline), and phentolamine methylate (Regitine).

An erection usually occurs within 5–20 minutes of an injection and lasts for 30–60 minutes. The effectiveness varies according to the drug used. For example, studies show that the response rate to papaverine is 65%, but for alprostadil, it's more than 80%. Doctors typically prescribe these drugs in some combination rather than singly; many men who don't respond to any of these drugs alone can get erections when they combine two or more. A preparation called Trimix contains a mixture of papaverine, phentolamine methylate, and prostaglandin. One study found Trimix aided 62% of men who did not otherwise respond to injection treatments.

The main side effects of the injections are mild to moderate pain, bruising, or scarring. Like Viagra, injectable drugs can also cause low blood pressure. Although rare, this side effect is most likely to occur if a man takes too large a dose or if he injects himself more than once in 24 hours.

Another rare complication is priapism, an erection that lasts too long. Any man who has an erection that lasts for more than three hours after an injection should go to an emergency room for an injection of a counteracting drug. An erection that lasts longer than six hours can cause scarring and complete loss of erectile function. Because of these potential side effects, doctors prescribe the lowest effective dose. A doctor or nurse usually gives a patient an injection in the office to establish what that dose is before writing a prescription.

If you're using injectable drugs, there are some things you can do to help the therapy feel more natural for you and your partner. One is to take a low dose and ask your partner for manual or oral stimulation to help achieve a full erection. That way, your partner will feel more involved. You might also suggest that your partner watch you inject yourself once or twice to help overcome any initial discomfort with the process. But if you're more comfortable doing this privately, that's fine, too. What's most important for the treatment's success — and for your emotional well-being — is that you and your partner feel at ease with it.

Last updated:	September 05, 2008