When Vikki Simpson took her 3-year-old to the doctor for an MMR vaccine, the last thing she expected was to end up in the hospital.

Little Leah didn’t cry when she first got the jab but just minutes later–much to her mother’s terror–Leah stopped breathing and turned blue, becoming limp and unresponsive.

In an article that’s gone viral on social media, Simpson shared her experience with the Berkshire News. She decided to tell her story because she wants to warn parents to wait at least 15 minutes at the doctor’s office after vaccination in case something goes wrong.

The fact that Simpson and her daughter were still at the doctor’s office probably saved Leah’s life.

The doctors in southern England, where this family lives, told Simpson that her daughter’s severe allergic response to the measles mumps rubella booster was “rare.”

But what the doctors didn’t mention to Simpson is that bad reactions to prescription drugs, including vaccines, are one of the main reasons that parents take their children to the ER, according to Centers for Disease Control and Prevention (CDC) Researchers who evaluated one year’s worth of data from the National Electronic Injury Surveillance System-Cooperative Adverse Drug Event Surveillance Project, a national database that analyses stratified samples of data from hospital emergency rooms across the country.

In a peer-reviewed “Original Investigation,” published in JAMA (JAMA is the Journal of the American Medical Association, one of the most prestigious scientific journals in the world) in November 2016, a team of four CDC scientists and two government consultants found that:

• Among children ages 5 and under, vaccine adverse reactions accounted for 17 percent of all adverse drug reactions that brought kids to the Emergency Room.
• Adverse vaccine reactions were the second most common adverse drug reaction, after antibiotics, for children ages 5 and under.
• Among children ages 6 to 19, vaccine adverse reactions accounted for 3.4 percent of all adverse drug reactions that brought kids to the Emergency Room.
• Among children ages 6 to 19, vaccine adverse reactions were the sixth most common adverse drug reaction.

“This study reminds us that it’s easy to lose sight of complications associated with these commonly prescribed drugs,” writes Dr. William T. Basco, Jr., M.D., a pediatrician and director of the Division of General Pediatrics at the Medical University of South Carolina, in a commentary published on MedScape.

Kelly Sutton, M.D., a doctor based in Fair Oaks, California who has been practicing medicine for over 40 years, says doctors need to be sure to document any adverse drug reactions, including to vaccines.

“Drug adverse events must be recorded in a child’s medical record to avoid increasingly severe allergic-type responses,” Sutton recommends.

Sutton urges physicians to make use of the government’s Vaccine Adverse Events Reporting System (VAERS), which is a passive reporting system established in 1990 designed to track adverse reactions to vaccines.

Sutton says, this reporting system “is often overlooked in both emergency departments and doctors’ offices.”

The National Vaccine Injury Compensation Program is another government system that promotes vaccine safety. NVICP compensates those who have suffered from vaccine injuries and families whose loved ones have died as a result of vaccines.

To date the National Vaccine Injury Compensation Program, a Federal “no fault” system funded by a consumer tax on every vial of vaccines sold in the United States, has paid $4.2 billion to injured families.

“Concerning reactions are more common than people think,” says Cammy Benton, M.D., a family physician in private practice in Huntersville, North Carolina.

“Doctors are trained that common reactions are ‘normal’ rather than potentially pathological,” Benton says. “But it’s important to realize that some children cannot be safely vaccinated.”

Anecdotally doctors may believe that adverse reactions to vaccines are “rare.”

Scientifically, as this CDC research shows, reactions to vaccines are a top reason parents rush children to the ER.