Make your own free website on
Reactions to Snake Venom Antisera: Study of pattern, severity and management at General Hospital, Anuradhapura


Sri Lanka is the home for 92 species of snakes including 5-6 deadly venomous land snakes 1,2. Snake bites are a major health problem in some parts of Sri Lanka. In the year 1996, 27082 cases of snake bites were reported from all over the island 3; out of these 0.6 cases proved fatal 3. The highest number of snake bites have been reported from the North Central province of Sri Lanka.

The General Hospital, Anuradhapura serves as the key center for the management of these cases. About 1000 patients of snake bites are admitted to this hospital annually. Out of these cases Russell's viper bites were the most common (48%). Common krait bites (9%), hump nosed viper bites (6.5%) and cobra bites (2%) were much less common. About one third were non venomous snake bites. All these cases received appropriate treatment with antivenom (AVS) whenever
SUMMARY: The objective of this descriptive prospective study was to document the therapeutic response and adverse reactions to antivenom serum (AVS) therapy in hospital practice. Sixty patients (44 males), with snake bite treated with AVS at the General Hospital, Anuradhapura, in 1998 were observed for adverse reactions. The mean age was 33.8 ± (SD 11.9) years. The offending snakes were identified by the well known characteristics of each type. Russell’s viper was the cause in 54% of patients, the common krait in 31%, and the cobra in 7% of cases. The overall reaction rate was 68%: mild 58%, moderate 36% and severe 2%. All recovered fully from adverse reactions. The mean time of onset of reaction was 40 (SD 16.2) minutes. The mean time duration of reaction after treatment was 21.7 (SD 17.3) minutes. Intravenous injections of hydrocortisone 400mg and chlopheniramine 10mg were the standard method of treatment administered. One patient needed treatment with subcutaneous adrenaline. The response for treatment was dramatic irrespective of the severity of the reaction. The reaction rate was not dose dependent (Chi square =2.03,p > 0.05). There was a significant reduction of reactions with repetitive administration of AVS. Atopic history was not predictive of adverse reactions and pyrogenic reactions such as rigor (65%) and urticaria (57%) were the commonest manifestations. These observations indicate that reaction to AVS treatment is common and that reactions can be effectively treated by intravenous hydrocortisone and chlopheniramine. As the reaction rate does not appear to be dose dependent patients should not be deprived of a full dose of AVS therapy when indicated. . An emergency tray with effective medications for anaphylaxis should be available before embarking on AVS therapy.

KEYWORDS: Antivenom, onset of reaction, duration of reaction, medication

S. A. M. Kularatne, MBBS, MD, MRCP, Consultant Physician, General Hospital, Anuradhapura.

Correspondence: Dr. S.A.M. Kularatne, Department of Medicine, Faculty of Medicine, University of Peradeniya, Peradeniya.

Next Page

Sri Lanka Journal of Medicine 2000; 9(1): 8 - 13

Previous Page