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Does the possibility of an impending transfusion justify the administration of medication in advance, so that unwanted allergic reactions would be avoided?

Three Part Question

In [patients with need of transfusion for any reason] is [the administration of pretransfusion medication essential] in [reducing the risk of allergic and febrile non-haemolytic transfusion reactions]?

Clinical Scenario

A 49 year old man with acute lumbodynia for more than 2 weeks for which he received 2 non-steroidal anti-inflammatory drug tablets daily, but with no other health relating conditions, comes to the emergency department referring meleana dejections. In the laboratory tests haematocrit is discovered to be 27%, thus a transfusion is obligatory. You wonder whether the premedicasion transfusion could prevent the appearance of any allergic or febrile non-haemolytic transfusion reactions.

Search Strategy

Medline 1966 - May 6th of 2012 using the OVID interface.
[((pretransfusion AND medication) OR (transfusion AND premedication)) AND prevention] Limited to humans and English language

Search Outcome

9 papers where found with 2 of them being relevant to this question. The first one of those was a Cochrane systematic review consisting of 3 papers and it was dated at 2010. This one is more contemporary that the other 2 papers which were dated at 2008. The second one, published in 2011, is a retrospective cohort study of 179 individuals.

Relevant Paper(s)

Author, date and country Patient group Study type (level of evidence) Outcomes Key results Study Weaknesses
Martí-Carvajal AJ, Solà I, González LE, Leon de Gonzalez G, Rodriguez-Malagon N.
Patients of any age or genre in need of transfusion. Anemia could be reasoned to anything, including non-hematologic or hematologic malignancies2 Parallel design RCTs 1 Crossover design RCT acetaminophen and diphenhydramine VS placebo for allergic reaction RR=0.13, 95% CI= 0.01 - 2.39 RR=1.45, 95% CI=0.78 - 2.72 This is a well performed review article. However the little number of studies included may have affected the results. The studies of this review are characterized with great heterogeneity when referring to pharmacotherapy and methodology. Moreover it may have provided more reliable results if the studies’ heterogeneity was omitted statistically, in order for them to be combined and metanalysed.
acetaminophen and diphenhydramine Vs placebo for febrile reactions RR=0.52, 95% CI=0.21 - 1.25 RR=1.77 95% CI=0.57 - 5.49
hydrocortisone pharmacotherapy VS diphenhydramine for febrile reactionsOR=2.38, 95% CI=1.07 - 5.26 (in favour of hydrocortisone harmacotherapy)
Tobian A.A.R., Savage W.J., Tisch D.T., Thoman S., King K.E., and Ness P.M.
179 individuals who received unmanipulated and subsequently concentrated and/or washed APsCohort Study Unmanipulated APs VS concentrated or washed APs in order to avoid allergic reactionsRelative to unmanipulated APs ART rates, concentrated APs resulted in a 73% reduction (p,0,001) Relative to unmanipulated APs ART rates, washed APs resulted in a 95% reduction (p,0,001) The results indicate clearly that receiving either concentrated or washed APs, when needed, induces the relative risk of an allergic reaction rather to unmanipulated APs. However no evidence about the medication received before each transfusion is provided. It is reported that the data concerning premedication administration were not available, thus they were not included in the analysis.


It is easy to understand that there is a clear gap in the actual knowledge of this topic currently. Premedication transfusion and the prevention of transfusion reactions neither have been excessively studied nor have been assessed through a metanalysis. However, the current knowledge implies that regardless of the patient’s history of non-hemolytic transfusion reactions and the use of leukodepleted blood products in the transfusion, pretransfusion medication do not help in preventing transfusion reactions. Something to be kept in mind is that the first paper, the systematic review, is based on three trials of moderate to low quality, so further research on the subject is necessary. As the cohort study indicates the concentrating and washing APs substantially reduce the number of ARTs, regardless premedication administration.

Clinical Bottom Line

Premedication transfusion does not seem to help reducing the risk of an allergic or febrile non-haemolytic transfusion reaction. Latest researches have added more evidence on the field of transfusion ARTs, indicating that the administration of concentrated or washed units, use of male-only plasma and restriction of erythrocyte storage age, even more beneficial than leykoreduction of erythrocyte units.


  1. Martí-Carvajal AJ, Solà I, González LE, Leon de Gonzalez G, Rodriguez-Malagon N. Pharmacological interventions for the prevention of allergic and febrile non-haemolytic transfusion reactions. Cochrane Database Syst Rev. 2010 Jun 16; (6):CD007539.
  2. Tobian AA, King KE, Ness PM. Prevention of febrile nonhemolytic and allergic transfusion reactions with pretransfusion medication: is this evidence-based medicine? Transfusion. 2008 Nov; 48(11):2274-6.