Anaphylaxis treatment: the details

Having read the review article by Anne Ellis and James Day,1 I have several questions about drug therapy for anaphylaxis.

Ellis and Day1 report that patients seen in their unit are usually discharged with a 4-day prescription for prednisone and diphenhydramine, a relatively common approach. However, given that many patients must drive or go to work, I wonder why the authors do not advocate one of the newer nonsedative antihistamines. Similarly, would it be appropriate to recommend the addition of ranitidine for 48 hours, on the basis of the experimental evidence presented by Ellis and Day1 and given the risk of a biphasic reaction? Since the second-phase reaction may be more severe than the primary reaction,1 this approach might be safer, although it is as yet unproved. I also wondered what dosage of prednisone is recommended for postdischarge therapy and whether the dose should be tapered.

Ellis and Day1 mention the cross-reactivity between cephalosporin and penicillin, but there have been conflicting recommendations as to whether this applies to the third-generation cephalosporins. Kelkar and Li2 recommended against prescribing third-generation cephalosporins to patients allergic to penicillin, but their review was based on extrapolation and inference. Anne and Reisman3 concluded that it is safe to administer cephalosporin antibiotics, especially third-generation drugs, to penicillin-allergic patients. Pumphrey and Davis4 reported 6 anaphylactic deaths after a first cephalosporin dose, which occurred over a 5-year period in the United Kingdom. Three of these patients had a penicillin allergy, but the generation of the cephalosporins in these cases was not indicated. In my own experience, many physicians in France are not reluctant to use third-generation cephalosporins, when indicated, for penicillin-allergic patients (in the hospital environment).

Finally, prescribing epinephrine as volumes of a 1:1000 solution is a potentially dangerous dosing system. Administering epinephrine measured in micrograms (or milligrams), as pumped from clearly labelled ampoules, might avoid inadvertent ventricular tachycardia.

Axel Ellrodt Emergency Department American Hospital of Paris Paris, France