Alprostadil, Caverject, MUSE, Viridal Duo and Vitaros are medications that are prescribed to treat erectile dysfunction. Alprostadil is the active ingredient in all of these treatments and they all belong to a group of medications known as PGE1s, or prostaglandins. These drugs are an effective alternative to the likes of Cialis and Viagra, which belong to a slightly different category called PDE5 inhibitors.

While PDE5 inhibitors are the most commonly prescribed treatments for erectile dysfunction, and are safe for the vast majority of people, they may not be suitable or effective for everyone. This might be due to a number of reasons, including interactions with other treatments. 

For example, you should not take Levitra if you are using nitrates to treat angina. As alprostadil is not swallowed via a tablet, it is not absorbed into the system in the same way and may therefore be better tolerated or suitable for people who cannot take PDE5 inhibitors. It should be noted, however, that side effects and interactions still exist for alprostadil treatments and it is important to know what these are.

Alprostadil drug interactions

All substances come with the possibility of interacting with others, this includes food, alcohol, herbal supplements, over the counter and prescription medications. Most medications will cause no issues in the body, but a few are likely to increase the risk of side effects occurring, while others might even present a serious risk to your health.

What’s more, everyone reacts differently to medication due to a number of factors, such as health issues (contraindications) and genetics, but there are a number of interactions that are well known. Your doctor will be able to adjust your treatment accordingly once they know what other medications or supplements you are taking.

Although the active ingredient (alprostadil) in Caverject, Viridal Duo, MUSE and Vitaros is the same, it could still be possible for them to cause different interactions because they’re administered in different ways. It is therefore important that you tell your doctor about any other treatments you are currently or have recently taken, including herbal medications and supplements. Only then will they be able to prescribe you a treatment for erectile dysfunction safely.

Interactions for Caverject

Tell your prescriber about any treatments you’re using during consultation. Caverject has the capacity to interact with: antihypertensives, sympathomimetics, vasodilative agents, other medicines for erectile dysfunction and blood thinners.

It’s also important to let your doctor know if you start taking the above while using Caverject. If you begin treatment with any of the above, you may be advised to stop using Caverject.

You should refer to the patient information leaflet that comes with Caverject before use.

Interactions for MUSE

MUSE is a urethral suppository, which means it is placed into the penis through the urethra (the hole at the tip of the penis) using a small device. Like Caverject, it may interact with: antihypertensives, anticoagulants, sympathomimetics, vasoactive, decongestants, appetite suppressants or other erectile dysfunction treatments.

You can also refer to the patient information leaflet that comes with MUSE for more information.

Interactions for Viridal Duo

Viridal Duo is similar to Caverject in that it is injected directly into the penis. It has just a few interactions that might make it unsuitable for use, which include: MAOI antidepressants, papaverine, phentolamine, other treatments for erectile dysfunction, blood thinners and drugs to lower blood pressure.

For further information, you can also refer to the patient information leaflet that comes with Viridal Duo.

Interactions for Vitaros

Vitaros is a cream that is applied to the penis through the urethra.

For the most part, it has no significant known interactions, but its use alongside some medications has not been properly understood, so you should speak to a doctor before use if you are on any of the following: other erectile dysfunction medications, muscle relaxants, alpha blockers, high blood pressure treatments, decongestants, appetite suppressants or blood thinners.

If in doubt, you can also refer to the patient information leaflet that comes with Vitaros.

Page last reviewed:  24/07/2020