Reviewed By: Pramod Kerkar, MD, FFARCSI

What is Biphasic Anaphylaxis?

Biphasic Anaphylaxis refers to the symptoms of anaphylaxis that reoccur after an initial attack of Anaphylaxis. The symptoms of anaphylaxis are usually very severe and peak rapidly. The symptoms of Biphasic Anaphylaxis are quite same but they are much less in severity. This does not mean that the symptoms of Biphasic Anaphylaxis should not be considered as serious in any way. This is precisely the reason as to why people who have had an anaphylactic reaction are observed in the hospital for up to three days so that they can be attended to immediately in case of Biphasic Anaphylaxis.

Many people who have a mild anaphylactic reaction do not bother to call emergency room and wait for the symptoms of anaphylaxis to resolve on its own but this is a bad practice as the symptoms of anaphylaxis may get worse within a matter of seconds and then it may become life threatening for the patient.

Studies suggest that it is extremely difficult to predict whether Biphasic Anaphylaxis will occur or not but case studies suggest that people who have reported low blood pressure as the first sign of anaphylactic reaction are more likely to get Biphasic Anaphylaxis than others.

When Does Biphasic Anaphylaxis Occur?

Biphasic Anaphylaxis can occur anywhere within one hour to even three days after the initial attack. However, in majority of the cases Biphasic Anaphylaxis occurs approximately 8 to 10 hours after the initial attack. In some cases, Biphasic Anaphylaxis can occur even after 72 hours of the initial attack.

What To Do For Biphasic Anaphylaxis?

The treatment for Biphasic Anaphylaxis remains the same as that for Anaphylaxis. Epinephrine or adrenaline is the frontline medication used to treat anaphylactic reaction. It works by opening up the airways and makes breathing easier.

Epinephrine is also available as an autoinjector and can be injected by the patient or by anyone at the time of an attack. It calms down the symptoms and gives time for the individual to go to the emergency room. EpiPen is the most preferred form of epinephrine used to treat Biphasic Anaphylaxis.

If an individual has a history of Anaphylaxis or is sensitive to allergens then it is recommended to carry an autoinjector to prevent any attack. It is quite easy to use by just opening the cap and injecting in the thigh or other fleshy part of the body.

The autoinjector can be administered through the clothing so it does not require the patient to be in an isolated or a private place to inject the medicine.

Pramod Kerkar

Written, Edited or Reviewed By:

, MD,FFARCSI

Pain Assist Inc.

Last Modified On: October 23, 2018

This article does not provide medical advice. See disclaimer

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