“…Unfortunately, specific antivenom against this species is not available, while the heterologous Indian polyvalent antivenoms (raised against the venoms of Indian Big Four: Indian cobra, Indian krait, saw-scaled viper, Russell's viper) were proven ineffective but risking hypersensitive reactions in the patients (Sellahewa and Kumararatne, 1994;Premawardena et al, 1996Premawardena et al, , 1998Joseph et al, 2007;Ariaratnam et al, 2008). Tan et al (2011aTan et al ( , 2012a demonstrated that Thai Hemato polyvalent antivenom (raised against Malaysian pit viper, white-lipped green pit viper and Siamese Russell's viper) conferred paraspecific protection against H. hypnale venom's various toxicities in mice; the findings of efficacy however still await clinical validation. Laboratory studies thus far confirmed the activities of enzymatic toxins like phospholipases A 2 (PLA 2 ), thrombin-like enzymes (TLE), proteolytic enzymes (snake venom metalloproteinases, SVMP) and Lamino acid oxidases (LAAO) in the venom (Wang et al, 1999a;Tan et al, 2011b).…”