Trimix is an injectable three-drug prescribed medication used to treat erectile dysfunction. The active ingredients in the mixture are usually alprostadil, papaverine, and phentolamine. The injection must be compounded by a pharmacy and administered via intracavernosal injection. Trimix is typically compounded by a pharmacy in a sterile environment and then frozen. The compound is stable for up to 6 months while stored frozen and for 1 month if stored refrigerated beginning at the time of manufacture.