Also Known As: Podophyllum, Podocon-25
Podophyllin has been used to remove genital warts since its efficacy was first demonstrated in 1942, although the reliability of this early report has been questioned. This requires one application of podophyllin resin a week to the warts by a health professional, which is then washed off after 4 to 6 hours. Petroleum jelly, such as Vaseline, may be used to protect normal tissue near the warts from irritation. A health professional usually applies the resin once a week for at least 6 weeks or until warts disappear. It is unstable and therefore must be prepared shortly before use, which has possibly led to the lower efficacy shown in some clinical trials.
Podophyllin is a resinous powder obtained by precipitating an alcoholic tincture of the rhizome of American Mayapple (Podophyllum peltatum) or Podophyllum emodi by means of water acidified with hydrochloric acid. It varies in color from grayish to bright yellow or greenish-brown, the first-named being the purest. It was commonly used against HPV induced genital warts because it contains antiwart lignans, although podofilox, a purified form of the main active ingredient, has become recommended due to its higher efficacy and safety.
The powder is soluble in alcohol and strong solutions of alkalis, such as ammonia. Its composition is somewhat complex. There are certainly at least two resins in the powder (which is known officially as Podophylli resina), one of them being soluble and the other insoluble in ether. Each of these contains an active substance, which can be obtained in crystalline form, and is known as podophyllotoxin. It is soluble in alcohol, ether, chloroform and boiling water.
In toxic doses podophyllin causes intense enteritis, with all its characteristic symptoms, and severe depression, which may end in death. The treatment is symptomatic, there being no specific antidote.
Even when podophyllin resin is used topically, it can be systemically absorbed into the body, and fatal and near-fatal reactions have been reported, particularly when it is used extensively or on mucous membranes. Neither podophyllin resin nor podofilox lotion or gel is used during pregnancy because these medications can be harmful to the fetus. The most common side effects near the application site are skin reactions, including burning, redness, pain, itching, swelling. There is some concern about the mutagenicity of some of the flavonoids in podophyllin.