Using penile injections for ED after prostate cancer treatment

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Penile injections to get an erection typically work very well, producing a firm erection in 9 out of 10 men when used together with sexual stimulation (foreplay). Those are pretty good odds, and penile injections can be a great option for some people. So, how exactly do they work? And can they be used after any prostate cancer treatment?

Can you use penile injections after prostate cancer surgery, radiation treatment, or hormone treatment?

Penile injections can be used to treat erectile dysfunction, no matter which prostate cancer treatment you’ve had. Whether it’s surgery, radiation, or hormone therapy, the injections work in the same way to help you get an erection. Talk to your doctor about any questions you have, including when’s the best time to start using injections.

How do penile injections work?

Having your penis injected with medication probably seems concerning, but don’t worry, the process sounds worse than it actually is. The needle used is small and your doctor or nurse will teach you how to correctly inject the medication into your penis. That’s right—you can do the injecting yourself.

The penile injection may consist of a single medication or contain a combination of 2 to 4 different medications. Your doctor will figure out which formulation to use and the dose that works best for you.

Depending on what your doctor ends up prescribing, the penile injection may be available as a brand name medication (for example, Edex, Prostaglandin E-1, Caverject, Viridal) or as a compounded medication (for example, BiMix, TriMix or QuadMix). The brand names of medications can vary depending on where you live — your doctor will know what's available.

Medication is injected directly into the side of your penis, along the shaft, using a small needle. The medicine widens the arteries within the penis and increases blood flow. The increase in blood flow is what helps you get a firm erection.

How long does it take for penile injections to work?

Penile injections can produce an erection in about 10 to 15 minutes. The injections work more quickly than ED pills, which is a benefit for those wanting a bit more spontaneity.

How long do penile injections last?

Once you’ve done your penile injection, the effect can last about 30 minutes.

Are penile injections painful?

It’s possible that you’ll experience some pain when you do a penile injection. But the small size of the needle and correctly following your doctor’s instructions will help.

There may also be some bruising or bleeding at the place of injection. It could happen for a short time after injection or when you experience the erection.

Here’s what men had to say about the injections:

I was surprised how easy and painlessly the needle went in. I did get some aching pain after but it’s really not bad.

It felt like a mosquito bite. Just a twinge – not painful like I expected. And definitely worth it!

What other side effects do penile injections have?

Like any medicine, penile injections can have side effects, but they are usually temporary.

    You might experience:

  • Prolonged erection. You could experience erections that don’t always go away after orgasm, but this should be temporary. If your erection continues for more than 4 hours, contact your doctor or go to your local hospital emergency room immediately. An erection for this amount of time can be dangerous.

  • Scarring and curving of the penis (rare). After using injections for a while, your erections may develop a curve. While this is a rare side effect, it’s important to speak to your doctor straightaway if you notice this happening.

Certain conditions can make penile injections risky to use. Make sure to tell your doctor if you have any of the following:

  • Sickle cell anemia or sickle cell trait

  • Leukemia

  • Lymphoma

  • Myeloma

  • Curvature of the penis from scar tissue (Peyronie’s disease)

Penile injections versus erection pills — what’s best?

Penile injections produce an erection in a similar way to ED pills — by increasing blood flow to the penis.

    But penile injections are usually considered when:

  • Erectile dysfunction pills haven’t worked well enough

  • You can’t tolerate the side effects of the pills

  • There are other reasons you can’t use the pills

If you’re weighing up what’s best for you and what you prefer, talk to your doctor to get a personalized recommendation. They may suggest a number of things you might not have considered, and it’s best to work together on this.

Overall, penile injections are a very effective way of producing erections, but like all sexual aids there are pros and cons. Speak to your doctor to decide whether they are worth trying for you, and how to use them correctly.