Snakebites can present local or systemic envenomation, while neurotoxicity and respiratory paralysis are the main cause of death. The mainstay of management is anti-snake venom (ASV), which is highly effective, but liable to cause severe adverse reactions including anaphylaxis. The types of adverse reaction to polyvalent anti-snake venom have not been previously studied in Bangladesh. In this prospective observational study carried out between 1999 and 2001, in the Snake Bite Study Clinic of Chittagong Medical College Hospital, 35 neurotoxic-snake-bite patients who had received polyvalent anti-snake venom were included while the ones sensitized to different antitoxins and suffering from atopy were excluded. The common neurotoxic features were ptosis (100%), external ophthalmoplegia (94.2%), dysphagia (77.1%), dysphonia (68.5%) and broken neck sign (80%). The percentage of anti-snake venom reaction cases was 88.57%; pyrogenic reaction was 80.64%; and anaphylaxis was 64.51%. The common features of anaphylaxis were urticaria (80%); vomiting and wheezing (40%); and angioedema (10%). The anti-snake venom reaction was treated mainly with adrenaline for anaphylaxis and paracetamol suppository in pyrogenic reactions. The average recovery time was 4.5 hours. Due to the danger of reactions the anti-snake venom should not be withheld from a snakebite victim when indicated and appropriate guidelines should be followed for its administration.

In tropical countries like Bangladesh, persons are bitten by snakes every day and a considerable number of patients die en route to the hospital. An event of consecutive neurotoxic bites on two men by a single snake was observed in the Snake Bite Study Clinic (SBSC) of the Chittagong Medical College Hospital (CMCH). Two brothers, working in their semi-pucca restaurant, were successively bitten by the same cobra on their lower limbs. Within an hour, they were taken to the CMCH. Few minutes after admission, both developed symptoms of neurotoxicity: ptosis, nasal voice, dysphagia, broken neck sign, etc. They received polyvalent antivenom (Haffkine Bio-Pharmaceuticals Company, India) and other auxiliary treatment immediately. Within few hours, neurotoxic features were completely absent. Later, the snake was captured in the restaurant kitchen and identified as monocellate cobra (Naja kauthia) by the SBSC. The elder brother developed significant antivenom reactions and both presented necrosis and ulceration at the bite sites. In these cases, immediate arrival to the hospital and early administration of antivenom resulted in successful recoveries.