Intraurethral suppositories are a specialized method for delivering medication directly to the male urethra, most commonly used for treating erectile dysfunction. This system utilizes a micro-suppository, often roughly the size of a grain of rice, contained within a single-use applicator device. The purpose of this localized delivery is to achieve a therapeutic effect within the penis while minimizing the systemic effects that can occur with oral medications. The most recognized example of this method is the Medicated Urethral Suppository for Erection (MUSE), which contains the drug alprostadil.
How Intraurethral Suppositories Deliver Medication
The tiny medicated pellet is deposited into the distal urethra, where it rapidly dissolves upon contact with the urethral mucosa. Urination immediately before administration is often advised, as the residual moisture helps disperse the medication for absorption.
The urethral tissue is highly vascularized, meaning it contains many small blood vessels that allow for quick uptake of the active ingredient, alprostadil. Alprostadil is a potent vasodilator, which causes blood vessels to expand and smooth muscle tissue to relax. The medication is absorbed into the underlying corpus spongiosum, which is the erectile tissue surrounding the urethra.
From the corpus spongiosum, the alprostadil is transported through small communicating vessels into the corpora cavernosa, the two main erectile chambers of the penis. This localized action causes the smooth muscle within the cavernosal arteries and the trabecular network to relax, dramatically increasing arterial inflow and trapping blood within the erectile bodies.
Proper Administration Technique
The first step involves preparation, specifically urinating to clear the urethra and provide the necessary moisture for the pellet to dissolve. After urination, the patient should gently shake the penis to remove excess moisture and then wash their hands thoroughly before handling the device.
The specialized applicator device is removed from its foil pouch and inspected to confirm the micro-suppository is visible at the tip. To begin the insertion, the patient should stretch the penis upright to its full length to straighten the urethra, which facilitates the passage of the applicator. The applicator stem is then slowly inserted into the urethral opening, or meatus, up to the collar of the device.
Once inserted, the button at the top of the applicator is pushed down completely to release the medicated pellet into the urethra. The applicator is held in place for approximately five seconds after pressing the button to ensure the pellet is fully released from the tip. The applicator is then gently rocked or moved side-to-side before being removed while the penis is still held upright.
The final and crucial step is to aid the absorption and distribution of the medication by holding the penis upright and rolling it firmly between the hands for at least ten seconds. This action helps spread the dissolved medication along the urethral walls and into the surrounding erectile tissue. The patient should then remain in a seated, standing, or walking position for several minutes as the medication begins to take effect and an erection develops.
Expected Results and Associated Risks
Patients generally begin to notice an effect within five to ten minutes following administration. The expected duration of the resulting erection is approximately 30 to 60 minutes, though the actual time can vary significantly from person to person.
Common side effects can occur, including minor bleeding or spotting from the urethra due to slight abrasion from the applicator. Localized pain, such as a burning sensation in the urethra or penis, is also frequently reported and may sometimes be alleviated by continuing to roll the penis after insertion. Other common systemic effects include dizziness or a mild headache.
Since the medication can cause blood pressure to drop, a small percentage of patients may experience symptomatic hypotension or fainting (syncope). The most serious potential complication is priapism, which is a prolonged erection lasting four hours or more. This condition is a medical emergency that requires immediate attention, as a sustained erection can cause permanent damage to the penile tissue.