Johnson & Johnson foot ulcer medication could heighten the risk of developing cancer – asserted the warning issued by the US Food and Drug Administration on Friday.

The FDA warned patients using large amounts of Regranex, the J&J’s foot ulcer cream, could heighten their risk of dying from cancer. The agency added its most serious warning to Regranex, which is prescribed to treat severe foot and leg ulcers in diabetics.

The new boxed warning from FDA read, the patients who used three or more tubes of Regranex over a 20-month period were five times more likely to die of cancer. The new label, which is outlined in a black box, advises doctors to use caution when prescribing the drug to patients with malignancies.

According to the FDA, the patients that used lower amounts of the cream, their chances of developing cancer were no higher than patients who had never used the drug.

The FDA in March said it was reviewing the drug's links to cancer. The findings came from a long-term analysis of records from health care providers comparing 1,600 patients who took Regranex with 2,800 patients who did not, according to the FDA.

Spokeswoman for New Brunswick, New Jersey based Johnson and Johnson said the company cooperated with FDA on the new label and is "committed to getting the information out to physicians and patients."

Regranex is a man-made version of a substance produced by the human body that helps heal ulcers. Because the drug causes cells to divide more rapidly, the FDA closely monitored patients for reports of cancer, which spreads through uncontrolled cell division. Over 750,000 people have used the drug since it was approved by the FDA in 1997. The drug is marketed by Ethicon Inc., a subsidiary of Johnson & Johnson. The shares of Johnson & Johnson fell $1.20 to close at $65.76 Friday.