ABSTRACT
HYPERSENSITIVITY REACTIONS Unlike chemotoxic contrast reactions, hypersensitivity reactions are independent of the rate or volume of contrast infusion. Immediate hypersensitivity reactions typically occur within seconds to an hour after contrast exposure. Delayed hypersensitivity reactions can occur between one hour and one week, but this is much less common. Hypersensitivity reactions typically present with some combination of pruritus, urticaria, rash, angioedema, laryngospasm, bronchospasm, hypotension, syncope, shock, or even death. Most such reactions are mild, but they can (rarely) be fatal.
