Linkus and insty are polyherbal medicines that are known to possess a variety of pharmacological activities such as anti-inflammatory, expectorant, bronchodilator, antispasmodic, antipyretic, mucolytic, etc. In this study, preclinical efficacy and toxicity of linkus and insty antipyretic extracts have been determined on animal models with yeast induced pyrexia. It has been found that linkus and instypolyherbal products possess significant antipyretic activity and exhibited no toxicity. They were found to have antipyretic activity similar to paracetamol, which was used as a control in this study. This work has provided genuine in-house generated information reflecting efficacy and toxicity of linkus and insty antipyretics, which will facilitate the registration process of these agents