Papain is used to dissociate cells in the first step of cell culture preparations. A 10-minute treatment of small tissue pieces (less than 1 mm cubed) will allow papain to begin breaking down the extracellular matrix molecules holding the cells together. After 10 minutes, the tissue should be treated with a protease inhibitor solution to stop the protease action (if left untreated papain's activity will lead to complete lysis of the cells). The tissue must then be triturated (passed quickly up and down through a Pasteur pipette) in order to break up the pieces of tissue into a single cell suspension.
It can also be found as an ingredient in some toothpastes or mints as teeth-whitener. Its whitening effect in toothpastes and mints however is minimal, because the papain is present in low concentrations, and will be quickly diluted by saliva. It would take several months of using the whitening product to have noticeably whiter teeth.
The agents are not approved by the FDA, and according to the latest FDA position/policy papers these products are not legally marketed.
On September 23, 2008, the FDA warned companies to stop marketing topical drug products containing papain by November 4, 2008. The FDA said, "No topical drug product containing papain has been approved by the FDA." According to the FDA's statement on the subject, "These unapproved products have put consumers health in jeopardy, from reports of permanent vision loss with unapproved balanced salt solutions to a serious drop in blood pressure and increased heart rate from the topical papain products," said Janet Woodcock, M.D., director for the Center for Drug Evaluation and Research. In the same FDA announcement, the FDA states the following:
About Unapproved Topical Papain Products: Topical drug ointments containing papain are used to remove dead or contaminated tissue in acute and chronic lesions, such as diabetic ulcers, pressure ulcers, varicose ulcers, and traumatic infected wounds. Trade names for these products include Accuzyme, Allanfil, Allanzyme, Ethezyme, Gladase, Kovia, Panafil, Pap Urea, and Ziox. Other products are marketed under the names of the active ingredients, for instance, papain-urea ointment.
The FDA is taking action today against these products because it has received reports of serious adverse events in patients using products containing papain. Reports include hypersensitivity (allergic) reactions that lead to hypotension (low blood pressure) and tachycardia (rapid heart rate). In addition, patients who are allergic to latex can also be allergic to papaya, the source of papain. Therefore, patients with latex sensitivity may be at increased risk of suffering an adverse reaction to a topical papain drug product.
FDA urges consumers who are using topical drug products containing papain, and who have questions or concerns, to contact their health care provider about discontinuing treatment with these products. There are a number of FDA-approved topical products that have been found safe and effective as wound healing agents and that do not contain papain.
"Removing unapproved topical drug products containing papain and unapproved ophthalmic balanced salt solutions is yet another step forward for patient safety," said Deborah M. Autor, director, Office of Compliance for CDER, FDA.