(CBSNews)--The U.S. Food and Drug Administration is warning pet owners of the risks associated with a skin cancer cream after five dogs were died after accidentally ingesting it.

The topical cancer medication Fluorouracil Cream USP 5% (5-FU), which is also be marketed under the brand names Carac, Effudex and Fluoroplex, is intended for use in humans.

In a statement released Wednesday, the FDA details the reports it received of five dogs that became ill and died after being exposed the cream.

In one case, two dogs were playing with a tube of Fluorouracil and one punctured the tube before their owner could retrieve it. Within two hours, the dog that punctured the tube began vomiting and experienced seizures. The dog died 12 hours later.

In a separate case, a dog found his owner’s tube of Fluorouracil and ingested its contents. The owner rushed him to the veterinarian, who attempted treatment, but the dog’s condition declined over three days and was ultimately euthanized.

To date, the FDA has not received any reports involving Fluorouracil and cats, but it says it expects that they are also extremely sensitive to the cream. If an owner applies Fluorouracil to an afflicted area and then touches a cat, the pet may accidentally ingest the medication when grooming itself and suffer adverse events, the agency warns.

The FDA recommends that people who use Fluorouracil take the following precautions to prevent their pets from accidentally ingesting it:

• Store all medications safely out of the reach of pets.
• Safely discard or clean any cloth or applicator that may retain medication and avoid leaving any residues of the medication on hands, clothing, carpeting or furniture.
• Consult your health care provider on whether it is appropriate to cover the treated area.
• If you are using topical medications containing Fluorouracil and your pet becomes exposed, consult a veterinarian immediately.
• If your pet shows signs such as vomiting, seizing or other illness, seek immediate veterinary care for your pet and be sure to provide the details of the exposure.

Pet owners and veterinarians can also report any adverse events to the FDA on its website.