A Medical ID provides information about you that may be important in an emergency, like allergies, medical conditions, and your emergency contacts. Your iPhone and Apple Watch can display this information so that it’s available for someone attending to you in an emergency and your emergency contacts can be notified if you on your iPhone.
Tap your picture at the top right, then tap Medical ID.
Tap Edit, scroll to the bottom, then turn on Show When Locked and Emergency Call.
Note: A first responder views your Medical ID from the Lock Screen by swiping up or pressing the Home button (depending on your iPhone model), tapping Emergency on the passcode screen, then tapping Medical ID.