Imagine what would happen if another person used your name and possibly your health insurance ID number or Social Security number in order to receive medical care — from a routine check-up or dental cleaning to filling a prescription or having surgery.

This type of crime is known as medical identity theft and it’s on the rise. The Federal Trade Commission (FTC) says it’s the fastest growing crime in the U.S. In 2012 as many as 10 million people were victims of medical ID theft, according to FBI statistics. Elderly people are especially vulnerable.

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How medical ID theft hurts your health

Having someone else benefit from your health insurance benefits obviously will take a toll on your finances, but the damage may not stop there. “In addition to having to deal with being the victim of a crime, your health is at stake,” says Eva Velasquez, president and CEO of the  Identity Theft Resource Center (ITRC), a nonprofit organization that helps ID theft victims.

“The thief’s medical records may become mixed up with yours,” she explains. For example, he or she may have a different blood type from yours, which could be fatal if you needed an emergency transfusion. Receiving the wrong blood type causes the body to launch an immune response that could lead to shock, kidney failure, circulatory problems and death.

Or a person who steals someone’s identity for medical treatment may be taking a prescription medication that shouldn’t be mixed with one you take, causing a pharmacist to refuse to fill a prescription you need.

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Protecting yourself against medical identity theft

Here are six ways to fight medical ID theft:

1. Safeguard your private information. Watch out for scammers who might try to get your information by offering you free medical supplies or services, calling your home with a fake survey or giving you groceries or other freebies, warns the Department of Health & Human Services.

3. Look for signs of medical ID theft. These include:

  • Suspicious bills or statements. If you get a bill for an emergency room visit for the flu, but you haven’t had so much as a sniffle, don’t assume it was a simple mix-up, Velasquez says.
  • Services you don’t recognize. Always check your explanation of benefits forms (EOBs) from your insurance provider for any doctor visits or treatments that aren’t yours.
  • A medical bill collection on your credit report. If an unpaid bill for the thief, using your name, is sent to a collection agency, that might then show up on your credit report as a medical collection. If you see a collection you don’t recognize, call the collection agency.

3. Get help. If you suspect a thief has used your identity to get medical services, contact the ITRC for free ID theft resolution assistance. Or, if you subscribe to an identity protection service, note that most offer help resolving ID theft. The FTC also has a step-by-step guide for victims.

4. Call the cops. If you’re a victim of medical ID theft, go to your local police department to file a report, then get copies of the report. It’s also smart to file a complaint with the FTC. You’ll get an ID theft affidavit to help prove that you’re a victim.

5. Do some detective work. It’s crucial to track down each instance where a thief may have used your information. Ask your health insurance company and your medical providers for an “accounting of disclosures” — a list of anyone who’s received your medical records. This list can help you figure out which medical providers have copies of your records.

6. Set the record straight. Correct all of your medical records. For each error that you find, send a letter by certified mail, with return receipt, to the medical provider. Include:

  • A letter explaining the problem and what needs to be done to fix it
  • A copy of the incorrect medical record
  • Your police report or affidavit from the FTC

You should receive a response within 30 days, according to the FTC. If your insurance company was involved, notify it as well.

Related: How to Protect Your Child from Identity Theft

Allie Johnson is an award-winning freelance consumer writer with a degree in magazine journalism. She lives in Georgia with her husband and two dogs.