How Long Do Allergic Reactions Last?

How Long an Allergic Reaction Could Last

The length of time an allergic reaction can last varies based on several factors. The type of allergic reaction, the amount of time the body is exposed to the allergen, and individual factors can all impact the duration of an allergic reaction.

Food Allergy

Food allergy symptoms typically begin a few minutes or two hours after someone eats or drinks. In some people, the onset of symptoms will disappear, and a second wave of symptoms may return one to 72 hours later, known as a biphasic reaction.

The length of time that food allergy symptoms last will vary based on the severity of the reaction, as well as how much of the food was eaten and for how long. Symptoms may last for a few minutes up to a couple of days.

Oral allergy syndrome is a type of food allergy where the mouth or throat becomes itchy after eating certain foods. It typically occurs within minutes of eating a fruit or vegetable.

Seasonal Allergy

Seasonal allergies, also known as hay fever, is a reaction to pollen, dust, or mold that tends to worsen during the spring, summer, or fall. People with seasonal allergies can experience symptoms for the entire time that they are exposed to the allergen, which can be for about six weeks during pollen seasons. If exposure to the allergen continues, then allergy symptoms can last for months.

Anaphylactic Allergic Reaction

An anaphylactic allergic reaction is a severe, whole-body allergic reaction that occurs within seconds to minutes of contact with an allergen. It is a life-threatening emergency that requires immediate medical attention.

Conclusion

Allergic reactions can last from a few minutes to several months, depending on the type of reaction and individual factors. Understanding the duration of an allergic reaction is important for proper treatment and management.

FAQs

• How long do food allergy symptoms last?
  • The length of time that food allergy symptoms last will vary based on the severity of the reaction, as well as how much of the food was eaten and for how long. Symptoms may last for a few minutes up to a couple of days.
• How long do seasonal allergy symptoms last?
  • People with seasonal allergies can experience symptoms for the entire time that they are exposed to the allergen, which can be for about six weeks during pollen seasons. If exposure to the allergen continues, then allergy symptoms can last for months.
• How long does an anaphylactic allergic reaction last?
  • An anaphylactic allergic reaction is a severe, whole-body allergic reaction that occurs within seconds to minutes of contact with an allergen. It is a life-threatening emergency that requires immediate medical attention.

Sources

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7. American Academy of Allergy, Asthma, & Immunology. Oral allergy syndrome (OAS).
8. DermNet. Allergies explained.
9. Asthma Allergy Foundation of America. Allergy treatments.
10. MedlinePlus. Allergic reactions.