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TF on Desensitisation Protocols in Drug Allergy

Topic area: Drug Allergy

If you are working in related fields, please help us collect protocols on desensitisation for antibiotics, chemotherapeutics and biologicals. Your contribution to this task force is essential and would be greatly appreciated.

Background
Drug hypersensitivity reactions can occur with most drugs, are unpredictable and their frequency and severity can vary from mild symptoms to potentially catastrophic complications. Reactions may affect any organ system in the body and range widely in clinical severity from mild pruritus to systemic anaphylaxis. Should a reaction occur it is imperative to recognise it quickly in order to minimise complications, implement appropriate therapeutic and supportive measures and avoid re-exposure to the eliciting agent.

For sensitised patients who have clinically meaningful benefit from a particular drug, however, continuation with the agent is desirable. One of the options includes desensitisation to the eliciting drug or treatment with a related non-cross reacting drug.

If a non-cross-reacting alternative drug, also effective, is available, then this will normally be used. In many circumstances alternative drugs are not the best choices. A desensitisation protocol, with the involved drug, may then be considered.  Acute or rapid desensitisation protocols have been developed and used in patients with allergic reactions to antibiotics (mainly penicillin) insulin, sulphonamides, chemotherapeutics agents and many other drugs. Many protocols rely on single case reports and it is confusing for the clinician to select the best protocol.

Desensitisations are done not only in presumed IgE mediated reactions, and they are high-risk procedures. They require the introduction of a medication to which the patient has reacted, done by repetitive increasing sub-threshold doses of the medication involved, until the total cumulative therapeutic dose is achieved. Once desensitisation is complete, this transient tolerant state can only be maintained by continuous administration of the medication – and for chemotherapy – with its 4 week intervals - this procedure is regularly repeated before a new course. The procedure is done quite often in the USA and to a variable degree in European countries.

Main Goals for the TF
1. Collect and compare protocols on desensitisation for antibiotics, chemotherapeutics and biologicals, using literature and own, European experience.
2. Define drugs and drug reactions amendable for rapid desensitisation. Provide criteria for the indications of rapid desensitisation, and establish a database via EAACI-homepage with standardized protocols for rapid desensitisation for antibiotics, for chemotherapeutic agents, for monoclonal antibodies and fusion proteins (“biologicals”) and some others (e.g. allopurinol).

The TF would like to select and propose well-documented protocols and make them available to interested doctors and their patients. The desensitization protocols collected so far are very few.

Contact Information
For submission of protocols on desensitisation for antibiotics, chemotherapeutics and biologicals, please contact:

Josefina Rodrigues Cernadas
Email adress:
Postal adress: R. Marta Mesquita da Câmara 124 1ºdto, Porto
CP 4150/485 for the TF