Ingenol mebutate, sold under the brand name Picato, is a substance that is found in the sap of the plant Euphorbia peplus,[1] commonly known as petty spurge, and is an inducer of apoptosis.

Additional possible side effects include eye irritation, such as periorbital edema (3% of patients in studies), headaches (2%) and nasopharyngitis (running nose, 2%).

[15] Results from four multicenter, randomized, double-blind studies have shown that ingenol mebutate gel applied topically, for 2 to the trunk or 3 days to the face or scalp, is effective for field treatment of actinic keratoses.

[17] Ingenol mebutate has also been found to be useful for reactivating latent HIV virus in cells taken from individuals who have tested negative for signs of the disease following extended courses of anti-retroviral drugs, raising the possibility that this drug may be used to expose the last traces of virus, and thus potentially provide a permanent cure for HIV infection.

Research is ongoing to determine whether the effects observed in vitro are also seen in animal models, with a view to eventual human trials for this application.

[19] Health Canada assessed twelve studies published in scientific and medical literature in order to determine the link between the use of ingenol mebutate and skin cancer.