The analgesics morphine and tramadol do not alter the acute toxicity induced by Bothrops asper snake venom in mice

- Analgesics tramadol and morphine were used in mice injected with Bothrops asper venom.
- Analgesics did not alter the acute toxicity of B. asper venom in mice.
- Precautionary (prophylactic) analgesia should be introduced routinely in Toxinology.