Interventions for preventing reactions to snake antivenom.
BACKGROUND
Antivenom is used to neutralise snake bite toxins in people showing evidence of envenomation. It is made from animal sera, and adverse effects, including life threatening anaphylaxis, are common.


OBJECTIVE
To assess the effects of drugs given routinely with snake antivenom to prevent adverse effects.


METHODS
Cochrane controlled trials register; contact with researchers in the field.


METHODS
Randomised and quasi-randomised trials testing routine adrenaline (epinephrine), antihistamines, or corticosteroids.


METHODS
The two authors applied the inclusion criteria, assessed trial quality, and extracted the data. We sought additional data from trialists where required.


RESULTS
One trial in Sri Lanka (n = 105) giving adrenaline with polyspecific antivenom showed fewer adverse reactions in the adrenaline group, and this effect was preserved when stratified for severity. One trial in Brazil (n = 101) using three types of Bothrops antivenom showed no benefit of antihistamine drugs.


CONCLUSIONS
Routine prophylactic adrenaline for polyvalent antivenom known to have high adverse event rates seems sensible, based on this one trial. If clinicians believe local factors do not justify routine adrenaline, then they should test their belief in a randomised trial. Antihistamine appears to be of no obvious benefit in preventing acute reactions from antivenoms.
Nuchpraryoon
I
I
Pediatrics, Faculty of Medicine, Chulalongkorn University, Rama IV Road, Bangkok, Thailand, 10330. fmedinp@md2.md.chula.ac.th
Garner
P
P
D000997:Antivenins / Q000009:adverse effects*; D004342:Drug Hypersensitivity / Q000209:etiology* / Q000517:prevention & control*; D004837:Epinephrine / Q000627:therapeutic use*; D005938:Glucocorticoids / Q000627:therapeutic use*; D006634:Histamine H1 Antagonists / Q000627:therapeutic use*; D006801:Humans; D012910:Snake Venoms
D000997:Antivenins; D005938:Glucocorticoids; D006634:Histamine H1 Antagonists; D012910:Snake Venoms; D004837:Epinephrine