Prophylaxis against early anaphylactic reactions to snake antivenomBMJ 1999; 319 doi: https://doi.org/10.1136/bmj.319.7214.920a (Published 02 October 1999) Cite this as: BMJ 1999;319:920
Stopping trials early may result in insufficient evidence being accrued
- Douglas E Ball (email@example.com), drug information pharmacist, department of pharmacy,
- Klara Tisocki, lecturer, department of clinical pharmacology
- University of Zimbabwe, PO Box A178 Avondale, Harare, Zimbabwe
- Hospital Vital Brazil, Instituto Butantan, 05503-900, Sao Paulo, Brazil
EDITOR—Fan et al's paper is the second in the BMJ recently to investigate prophylaxis against adverse effects of snake antivenom.1 Earlier, Premawardhena et al in Sri Lanka concluded that giving low dose subcutaneous adrenaline before antivenom could prevent acute adverse reactions.2 The Brazilian study (by Fan et al) showed no benefit in using promethazine as pretreatment.1 Perhaps more interesting than the conclusions, however, is that both these clinical trials were stopped early because of interim analyses; they provide examples of the use and pitfalls of such analyses.
The Sri Lankan group stopped recruitment halfway through its …