The Medicated Urethral System for Erection, or Muse, is a treatment for erectile dysfunction (ED). It consists of a small, pre-filled applicator that introduces a medicated pellet directly into the urethra, the tube through which urine exits the body. This method provides a different approach for individuals who may not be candidates for or have not had success with other forms of ED treatment. The system is designed for self-administration.
The Mechanism of Muse
The active ingredient in Muse is alprostadil, a synthetic version of a naturally occurring substance called prostaglandin E1 (PGE1). When the alprostadil pellet is delivered into the urethra, it is absorbed through the urethral wall into the surrounding erectile tissues of the penis. Once absorbed, alprostadil relaxes the smooth muscle within the arteries of the penis. This relaxation causes the blood vessels to widen, a process known as vasodilation. The widened arteries allow a greater volume of blood to flow into the two chambers of spongy tissue within the penis, called the corpora cavernosa, resulting in an erection.
How to Administer Muse
Administering Muse begins with urination. Emptying the bladder lubricates the urethra, which facilitates inserting the applicator. After urinating, the protective cover should be removed from the Muse applicator, being careful not to touch the sterile tip. The applicator is designed to be inserted about half an inch into the urethra.
To position for administration, a man can either stand or sit. He should gently stretch the penis upward to its full length, which helps to straighten the urethra. Once the applicator stem is inserted into the opening of the penis, the button on the end of the applicator is pressed firmly to release the medicated pellet into the urethra.
After the pellet has been delivered, the applicator is removed. The next step involves massaging the penis gently but firmly for at least 10 seconds. This massage helps to ensure the pellet dissolves and the medication is distributed evenly along the urethral wall.
Effectiveness and Onset of Action
Clinical studies have shown that approximately 65% of men using the treatment were able to achieve successful sexual intercourse. The success of the treatment often depends on finding the correct dosage, with options ranging from 125 to 1000 micrograms of alprostadil. A healthcare provider will determine the appropriate starting dose.
An erection begins within five to ten minutes after the medication is administered. This is because the medication is absorbed directly at the site of action, bypassing the digestive system. The resulting erection generally lasts between 30 and 60 minutes. The medication is also metabolized quickly, with about 80% of the dose being absorbed within the first 10 minutes.
Side Effects and Safety Precautions
The most common side effect reported by users is a sensation of pain or burning in the penis, which occurred in nearly a third of patients in clinical trials. Other potential user side effects include minor bleeding or spotting from the urethra due to the applicator, dizziness, and headache. Most instances of pain are described as mild and temporary.
It is also possible for a female partner to experience side effects during intercourse. If the medication is transferred, she might feel vaginal burning or itching. To prevent this transfer of medication, the use of a condom is recommended.
Men who have conditions that predispose them to priapism, such as sickle cell anemia, or those with an abnormally shaped penis, should avoid Muse. A rare but serious risk is priapism, an erection that lasts for more than four hours and requires immediate medical attention. Driving or operating heavy machinery is not recommended after use due to the risk of low blood pressure and fainting.
Muse in Comparison to Other Treatments
Oral medications for ED, such as PDE5 inhibitors, work systemically, meaning they circulate throughout the body, whereas Muse acts locally on the penile tissues. This localized action results in a much faster onset, within 10 minutes, compared to the 30-60 minutes often required for pills. However, the need for urethral self-administration makes it less spontaneous than taking a pill.
In contrast to penile injections, which also use alprostadil, Muse is less invasive. Penile injections require inserting a needle directly into the side of the penis, a method that many find daunting. While studies suggest that injections may be more effective for a higher percentage of men, Muse provides a needle-free alternative. The choice between these treatments depends on balancing effectiveness, invasiveness, and personal comfort.