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Dr Swapnil Pawar May 16, 2021 683

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    Dr Swapnil Pawar


Written by – Dr Andrew Lam

Anaphylactic vs. Anaphylactoid Reactions


Anaphylaxis Anaphylactoid Reaction
Sensitisation Required? Yes – Requires previous exposure to allergen for significant reaction to occur No – reaction can occur on first exposure to the suspected substance
Pathophysiology Mediated by IgE – triggers a reaction that stimulates degranulation of mast cells and histamine release along with other mediators The substance causes a direct release of histamine and other mediators from mast cells – often complement-mediated
Amount of Allergen Required Minimal More than Anaphylaxis
Predicted by Allergen Skin Testing? Yes No


Management of Anaphylaxis


  • IM Adrenaline (0.3-0.5mg to the lateral thigh. If symptoms persist, can consider repeating dose every 5-15 minutes. However, if symptoms are refractory, prepare for an adrenaline infusion)
  • If signs of bronchospasm present and refractory to adrenaline, consider 5mg of salbutamol through a nebuliser
  • Deliver O2, up to 15L via a non-rebreather mask as required to maintain adequate SPO2
  • Adequate fluid resuscitation with 20ml/kg of normal saline if the patient is shocked, and repeat as necessary
  • Place the patient in the supine position, ideally with lower limbs elevated to support perfusion to vital organs
  • Hydrocortisone 200mg IV for management of delayed immune reaction secondary to anaphylaxis

If Refractory

  • Adrenaline infusion commencing at 1mcg/kg/min, titrating according to vital signs and clinical response of the patient
  • Vasopressor support (in addition to adrenaline) for patients with for maintenance of blood pressure and prevention of shock
  • Glucagon for a patient with beta-blocker therapy who may not respond to adrenaline, given as a bolus followed by infusion.  


Campbell, R.L., Kelso, J.M. (2021). Anaphylaxis: Emergency Treatment. UpToDate. Retrieved May 16, from


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Management of Febrile Neutropenia

Dr Swapnil Pawar May 11, 2021

play_arrow Management of Febrile Neutropenia Dr Swapnil Pawar   Written by – Dr Hyreim Su Treatment algorithm for febrile neutropenia References  Febrile neutropenia,, BMJ Best Practice, 2021 

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