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Allergic Reaction (cont.)

When Should Someone Seek Medical Care for an Allergic Reaction?

Because allergic reactions can progress and worsen in minutes, causing complications, medical attention is always recommended for all but the most minor and localized symptoms.

If the symptoms of an allergic reaction worsen over a few days, or if they do not improve with recommended treatment and removal of the allergen, call a doctor.

People should tell a doctor if they have any allergic symptoms after using a prescribed drug or other treatment prescribed (see Drug Allergy).

Allergic reactions can be dangerous. Sudden, severe, widespread reactions require emergency evaluation by a physician. Call 9-1-1 or activate emergency medical services if someone has any of the following with an allergic reaction:

  • Sudden, severe, or rapidly worsening symptoms
  • Exposure to an allergen that previously caused severe or bad reactions
  • Swelling of the face, lips, tongue, or throat
  • Wheezing, chest tightness, loud breathing, trouble breathing, or hoarseness of voice
  • Confusion, sweating, nausea, or vomiting
  • Widespread rash or severe hives
  • Lightheadedness, collapse, or unconsciousness

What Tests Do Health Care Professionals Use to Diagnose an Allergic Reaction?

For typical allergic reactions, a doctor will examine an individual and ask questions about his or her symptoms and their timing. Blood tests and X-rays are not needed except under unusual circumstances.

In the case of severe reactions, an individual will be evaluated quickly in an emergency department in order to make a diagnosis. The first step for the doctor is to judge the severity of the allergic reaction.

  • Blood pressure and pulse are checked.
  • An examination determines whether the patient needs help breathing.
  • Often, an IV line is placed in case anti-allergy (antihistamine) medications are needed quickly.
  • If the patient can speak, he or she will be asked about allergy triggers and previous reactions.
Last Reviewed 9/11/2017

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Allergic Reaction - Drug Allergy

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