A Veterinarian’s Defense of Microchipping Our Pets

Internet rumors that microchips cause cancer are proliferating — again. Well, don’t believe them.

Microchips are responsible for reuniting countless lost pets with their humans. By: Isabelle Blanchemain

There is renewed buzz around the internet that microchips cause cancer in dogs and cats.

I say renewed buzz because this fear-inducing story has been circulating for over 10 years.  Proponents of natural and holistic animal health care are usually the folks behind the sensational posts about microchips causing cancer. I’d like to set the record straight.

I also hope that everyone considers a microchip if you have fear of losing your beloved pet. Microchips are safe.


Anyone who has sat in an empty home, staring out a window hoping to see their lost pet show up can identify with that horrible feeling of guilt and sadness. Is Buffy dead or alive? Was she hit by a car? Lost in the woods? Is she lying hurt by the side of a highway?

Word that Buffy has been recovered because of her microchip is — well, there are no words. Pure relief, jubilation and an outpouring of gratitude describe the feeling of being united with a lost pet.

To date, there is evidence of 2 tumors at the site of a microchip in the millions of pets microchipped in the United States, and 2 tumors in 3.7 million pets in the UK over a 13-year-long span. All in all, the risk of microchips causing tumors at the site of implantation is minuscule.

Where It All Began

In the early 2000s, multiple studies involving laboratory mice or rats found that microchips caused foreign body-induced tumors in approximately 0.8–1% of the rodents.

These mice and rats were already being used in cancer studies, so they were not a random, genetically varied population. The researchers claimed that this evidence could not be used as evidence of microchips causing tumors in dogs, cats or humans. But people grabbed on to it anyway and went down the road of alternative fact-mongering.

In 2007, ABC news reported the mice story because Alzheimer’s patients were beginning to be microchipped. Based on the rodent studies, the FDA felt that more research should be done before claiming microchips are completely benign in humans. ABC added a quote from a cancer researcher saying he would not put one of those things (microchip) in his pet, sensationalizing the story quite a bit.

The American Medical Veterinary Association believes that microchips are safe for our fuzzy friends. By: Maja Dumat

A Great Safety Record

It has been over 10 years since these laboratory animal studies and that ABC news coverage.

In those 10 years, millions more cats and dogs have been microchipped with very little reason for concern. In 2013, the American Veterinary Medical Association published its opinion of microchips, claiming them safe and documenting only 2 cases of skin tumors related to microchips: 1 in a dog and 1 in a cat.

Risks vs. Benefits

Since we now have such a huge sample size of microchipped pets spanning over 2 decades, evidence shows that tumors caused by microchips are an extremely rare occurrence. Weigh that against the importance microchips play in recovering lost pets, and it is a no-brainer.

Personally, I have reunited lost pets with their humans multiple times because I found a microchip implanted in the little orphan Annie who showed up at my veterinary hospital. Joy all around when I call number from the microchip information to say that Annie is safe and sound, and can be picked up any time. My recoveries have been local, but there are reports of pets found and reunited after traveling 1,000 miles away from home!

I have never seen even a mild skin reaction to a microchip, although they can occur rarely. Unless you have an insurance policy from the great beyond that your pet is never going to run out of an open door or jump a fence or wander beyond safe territory, I would encourage you to consider a microchip.

If your pet is precious to you, your 12mm microchip is worth 12 million times its weight in gold.


This pet health content was written by a veterinarian, Dr. Debora Lichtenberg, VMD. It was last reviewed Jun 28, 2017.

Dr. Debora Lichtenberg, VMD

View posts by Dr. Debora Lichtenberg, VMD
Dr. Debora Lichtenberg, VMD, is a small animal and exotics veterinarian who has split her time between a veterinary practice in Pelham, Massachusetts, and her studio in New York City. Dr. Lichtenberg is a graduate of the University of Pennsylvania School of Veterinary Medicine with 30 years of experience. Her special interests are soft tissue surgery and oncology.

Please share this with your friends below:

Also Popular