Some Americans may need to avoid the COVID-19 vaccine for allergies to pharmaceuticals, those with food allergies have the green light to get the shot.

The most common food allergies listed in the study were shellfish, which affects an estimated 7.2 million U.S. adults, followed by milk, peanuts, tree nuts, fin fish, eggs, wheat, soy and sesame.

Such an allergy could cause more symptoms than just a rash, including low blood pressure and difficulty breathing, so you need to find out if you are allergic to shellfish.