Topical therapies

What are topical therapies?

Topical therapies means medications are applied to the skin. Two specific formulations of alprostadil have been approved for topical therapy. The first one is the urethral pellet medication inserted into the tip of the penis (intraurethral). The second one is a cream formulation applied to the external opening of the urethra at the tip of the penis.

When should I consider topical therapies?

Alprostadil is a well-known drug for the treatment of ED. Commonly they are considered as the second-line therapy but they can be a first-line treatment option also. The major advantage of alprostadil cream is that adverse events are very rare and there are no interactions with other drugs (e.g. blood pressure medications, blood thinners such as heparin or warfarin).

How do topical therapies work?

Alprostadil is absorbed from the urethra and relax smooth muscle in the vessels of the penis to increase blood flow. Alprostadil cream includes a permeation enhancer in order to facilitate absorption of alprostadil. The mechanism of action is similar to intraurethral alprostadil.

When are topical therapies not recommended?

You should not use alprostadil if you are allergic to it, or if you have:

  • sickle cell anaemia or the sickle cell anaemia trait
  • leukaemia
  • a tumour of the bone marrow (multiple myeloma)
  • a curved or deformed penis
  • penile fibrosis or Peyronie’s disease
  • if you have a penile implant

What are the side effects?

The most common adverse events of intraurethral alprostadil are local pain and dizziness with possible hypotension. In some cases, urethral bleeding and urinary tract infections occur while penile fibrosis and priapism are very rare.
Topical alprostadil has the advantage of only topical side effects that include penile erythema, penile burning and pain. Systemic side-effects are very rare.

To make sure alprostadil is safe for you, tell your doctor if you have:

  • a history of blood clots
  • heart disease, high blood pressure (hypertension)
  • a bleeding or blood-clotting disorder; or
  • a disease that could be passed in blood (such as hepatitis or HIV).

Use a condom to prevent transfer of this medicine to your sexual partner.