What is an Allergy? (S01E13)

The doctors explore the skin's role in shielding the body from extreme temperatures by immersing their hands in a liquid that freezes on contact. Dr. Chris heads to an allergy clinic to learn more about allergic reactions, meeting two patients whose suspected allergies are put through rigorous testing. The emergency ambulance crew assists a woman suffering from intense abdominal pain. Meanwhile, in the accident and emergency department, things take a quirky turn when one patient arrives with a broken 'banana' arm and another seeks treatment for a burn sustained from fried onions falling on her foot.