Because of the potential for symptomatic hypotension and syncope, which occurred in 3% and 0.4%, respectively, of patients during in-clinic dosing, MUSE titration should be carried out under medical supervision. During post-marketing surveillance syncope occurring within one hour of administration has been reported. Patients should be cautioned to avoid activities, such as driving or hazardous tasks, where injury could result if hypotension or syncope were to occur after MUSE administration.
There is currently no manufacturer warning information available for this drug.
MUSE is indicated for the treatment of erectile dysfunction. Studies that established benefit demonstrated improvements in success rates for sexual intercourse compared with similarly administered placebo.
MUSE® (alprostadil) is a single-use, medicated transurethral system for the delivery of alprostadil to the male urethra. Alprostadil is suspended in polyethylene glycol 1450 (as excipient) and is formed into a medicated pellet (micro-suppository measuring 1.4 mm in diameter by 3 mm or 6 mm in length) that resides in the tip of a translucent hollow applicator. MUSE is administered by inserting the applicator stem into the urethra after urination. The pellet containing alprostadil is delivered by depressing the applicator button (see Figure 1). The components of the delivery system are constructed of medical grade polypropylene. Each MUSE system is packaged in an individual foil pouch.
Figure 1: Diagram of the MUSE Transurethral System
The active ingredient in MUSE is alprostadil, which is chemically identical to the naturally occurring eicosanoid, prostaglandin E1 (PGE1). The chemical name for alprostadil is prost-13-en-1-oic acid, 11,15-dihydroxy-9-oxo-(11α,13E,15S)-(1R,2R,3R)-3-hydroxy-2-[(E)-(3S)-3-hydroxy-1-octenyl]-5-oxo-cyclopentane heptanoic acid, and the molecular weight is 354.49. The empirical formula is C20H34O5. The structural formula of alprostadil is represented below:
Alprostadil is a white to off-white crystalline powder with a melting point between 115° and 116°C. Its solubility at 35°C is 8000 mcg per 100 mL double-distilled water. The inactive ingredient in MUSE is polyethylene glycol 1450, USP. There are no other active agents or excipients in MUSE.
MUSE is available in 4 dosage strengths: 125 mcg, 250 mcg, 500 mcg, and 1000 mcg.