title: Parallel infusion of hydrocortisone +/- chlorpheniramine bolus injection to prevent acute adverse reactions to antivenom for snakebites.
abstract: OBJECTIVE
  To investigate the efficacy of continuous infusion of hydrocortisone with or without chlorpheniramine bolus against early adverse reactions to polyspecific antivenom.
  
  
  METHODS
  Prospective, double-blind, randomised, placebo-controlled trial at General Hospital, Anuradhapura, Sri Lanka.
  
  
  METHODS
  52 patients with snake envenoming were randomised to receive infusion of hydrocortisone (Group A), hydrocortisone with chlorpheniramine bolus (Group B) or placebo (Group C) during the administration of antivenom.
  
  
  METHODS
  Hydrocortisone 1000 mg in 300 mL of normal saline infusion was started 5 min before and continued for 30 min after antivenom. Chlorpheniramine 10 mg intravenous bolus dose was given 5 min after commencement of antivenom.
  
  
  METHODS
  Occurrence and severity of adverse reactions to antivenom.
  
  
  RESULTS
  Adverse reactions were observed in 80% (12/15) of Group A, 52% (11/21) of Group B, and 81% (13/16) of Group C. Reactions were mild or moderate except in two patients. A significant reduction in the number of adverse reactions was seen in Group B compared with the placebo group (difference, 29 percentage points; 95% CI, 0.2 to 58 percentage points). There was no significant difference between Group A and the placebo group.
  
  
  CONCLUSIONS
  Prophylaxis with a parallel hydrocortisone infusion alone is ineffective in reducing the occurrence of acute adverse reaction to antivenom serum, but combining it with chlorpheniramine seems efficacious.
authors.affiliation: Faculty of Medicine, Peradeniya University, Sri Lanka.
authors.forename: Indika Bandara
authors.initials: IB
authors.lastname: Gawarammana
authors.forename: S Abeysingha M
authors.initials: SA
authors.lastname: Kularatne
authors.forename: Wasantha P
authors.initials: WP
authors.lastname: Dissanayake
authors.forename: Ranjith P V
authors.initials: RP
authors.lastname: Kumarasiri
authors.forename: Nimal
authors.initials: N
authors.lastname: Senanayake
authors.forename: H
authors.initials: H
authors.lastname: Ariyasena
mesh_terms: D000328:Adult; D018926:Anti-Allergic Agents / Q000008:administration & dosage*; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage*; D000997:Antivenins / Q000009:adverse effects*; D002744:Chlorpheniramine / Q000008:administration & dosage*; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000008:administration & dosage*; D007022:Hypotension / Q000139:chemically induced / Q000188:drug therapy / Q000517:prevention & control; D007262:Infusions, Intravenous; D007275:Injections, Intravenous; D008297:Male; D011446:Prospective Studies; D012909:Snake Bites / Q000188:drug therapy*; D012910:Snake Venoms; D013610:Tachycardia / Q000188:drug therapy / Q000209:etiology / Q000517:prevention & control; D016896:Treatment Outcome; D014581:Urticaria / Q000139:chemically induced / Q000188:drug therapy / Q000517:prevention & control
chemical_list: D018926:Anti-Allergic Agents; D000893:Anti-Inflammatory Agents; D000997:Antivenins; D012910:Snake Venoms; D002744:Chlorpheniramine; D006854:Hydrocortisone