Trimix is a prescription drug cocktail used as a treatment for erectile dysfunction (ED). The name refers to the combination of three drugs: papaverine; phentolamine; and prostaglandin E1 (PGE1), also known as alprostadil. Trimix is often prescribed when other forms of ED treatment, such as solo injections of PGE1, have not been effective. It tends to work best when administered as an intracavernous injection, which is in the base of the penis. The drug is also available in gel form.
In injectable form, this drug combination is not marketed as a pre-prepared product. Pharmacists typically mix the trimix drug cocktail as requested by prescription. Once the drugs are combined, the mixture has a limited shelf life. It can last a month if refrigerated and up to six months if frozen.
Though intracavernous injection is the most common method of administering trimix, some patients are either reluctant or unable to take the drug in this manner. These individuals can use the topical version of the drug cocktail. This form of the drug is marketed as a single product. The mixture comes as a powder and is turned into a gel right before use.
PGE1 or alprostadil is a prostaglandin drug. It works by relaxing and regulating the function of the muscles in the penis. This is partially accomplished by widening the walls of the blood vessels in the area.
Papaverine is a vasodilator drug. It helps to manage muscle spasms by relaxing the blood vessels. This drug can be formulated to have a local effect, thus not increasing blood flow in other parts of the body.
Phentolamine is from the alpha-adrenergic antagonist class of drugs. It is an alpha blocker that helps to combat anxiety. As a part of trimix, it is primarily used to increase blood flow to the penis by also expanding the blood vessels.
However the drug is taken, it is typically administered shortly before anticipated sexual activity. It is meant to provide results within minutes. The effect should last approximately an hour. If it lasts much more than an hour, then the patient should seek immediate medical attention.
Other combinations of drugs can be used to provide an effect similar to trimix. A simpler two-drug cocktail known as bimix, which consists of only phentolamine and papaverine, is also available. As with the three drug version, pharmacists typically mix it by request and it also has a limited shelf life once combined.