African Journal of
Pharmacy and Pharmacology

  • Abbreviation: Afr. J. Pharm. Pharmacol.
  • Language: English
  • ISSN: 1996-0816
  • DOI: 10.5897/AJPP
  • Start Year: 2007
  • Published Articles: 2208

Article in Press

Analgesic properties of snake venom as compared to conventional analgesics

Caroline Moraa Gesisa1* and Joseph Gikunju Kangangi2

  •  Received: 19 May 2017
  •  Accepted: 14 June 2017
An analgesic is a drug that relieves pain by acting on the central nervous system or peripheral pain receptor mechanisms; while snake venom is a highly modified saliva containing zootoxins which facilitate the immobilization and digestion of prey and defense against threats. Snake venom is toxic but may also have therapeutic effects, e.g. captopril, an Angiotensin-Converting Enzyme inhibitor was developed from the Pit viper (Bothrops jararaca) venom. This study used the hot plate method in evaluation of analgesic activity. The method measures the nociceptive responses of mice when they are placed on a warmed plate between 55-56°C. Four analgesics namely morphine, pethidine, paracetamol and diclofenac were tested in mice and their analgesic properties compared to those of five snake venoms of the black mamba (Dendroaspis polylepis), green mamba (Dendroaspis angusticeps), puff adder (Bitis arietans), forest cobra (Naja melanoleuca) and the black-necked spitting cobra (Naja nigricollis). Snake venom was diluted 100 times using normal saline before being administered to mice. Normal saline was used as control. Black mamba venom showed the highest degree of analgesic activity at 39.2 s, followed by the puff adder venom at 25.2 s, black-necked spitting cobra at 21.6 s, forest cobra at 20.8 s and green mamba at 18.4 s. In comparison to known analgesics, morphine showed the highest degree of analgesic activity at 42.2 s, followed by pethidine at 37.4 s, diclofenac at 29.2 s and paracetamol at 22.2 s. Mice injected with the control reacted after an average of 13.0 s showing that the snake venoms and drugs tested in mice showed various degrees of analgesic activity. This study provides valuable information for the discovery of new analgesic medicines using snake venom. "All substances are poisons, there is none which is not poison. The right dose differentiates a poison and a remedy." Paracelsus.