A severe allergic reaction will usually occur
within what time period following exposure to the
substance to which the patient is allergic?

Most severe allergic reactions occur within seconds or minutes after exposure to the allergen. Some reactions can occur after several hours, particularly if the allergen causes a reaction after it has been touched or eaten. In very rare cases, reactions develop after 24 hours.

People need to distract themselves with actitives. they can also find a natural high. an example would be eating alot of meat. that meat can release dopamine to the brain which gives one a natural high feeling.