The peptide exenatide, which is present in the lizard Heloderma suspectum, is quite similar to the one found in GLP-1. This GLP-1 receptor agonist has a substantially longer biological halflife than GLP-1 and is administered sub-cutaneously twice daily for therapeutic purposes. There are two parts to this experimental investigation. We monitored acute toxicity for 14 days and sub-acute toxicity for 28 days. Under the skin, participants in an acute toxicity trial took 200–800 mg/kg of exenatide in a single dosage. Researchers looked at subacute toxicity by administering 150 mg/kg/day, 250 mg/kg/day, and 500 mg/kg/day dosages for 28 days. Tests on rats at doses up to 800 mg/kg revealed no harmful effects, alterations in behaviour, or mortality. Thus, a subcutaneous hazardous dosage with an LD50 greater than 800 mg/ml is required. Also, sub-acute toxicity experiments validated the drug's safety, and rats given doses of 1 mg/kg, 10 mg/kg, and 100 mg/kg did not exhibit any clinical signs, variations in biochemistry, or histology when compared to the control group (p<0.05). It follows that exenatide is safe for use in future research.