Ex-Lax Off Shelves; Fda Cites Cancer Risk

The maker of Ex-Lax, the country’s top-selling laxative, pulled the product off store shelves Friday after the government announced it intends to ban an over-the-counter laxative ingredient linked to cancer.

Novartis Consumer Health emphasized that after more than 90 years of use in Ex-Lax, it believes the ingredient phenolphthalein is safe, but that it would reformulate the longstanding product “to avoid consumer confusion.”

The Food and Drug Administration did acknowledge that it has no reports that phenolphthalein has caused cancer in people.

But the FDA said animal studies found phenolphthalein, at high doses, could damage a vital gene that suppresses tumors, and consequently caused a variety of cancers in laboratory mice and rats.

The damage to the p53 gene was disturbing enough that the FDA concluded it posed a potential cancer risk to people who use phenolphthalein-containing laxatives for extended periods of time or at higher-than-recommended doses.

“It’s very hard to draw a line” at which a laxative user could be at risk, cautioned FDA drug chief Dr. Robert Temple. “The concern is for long-term use, and it’s greater the longer the use and the higher doses people use.”