Noscapine ((S,R)-Noscapine) is an alkaloid derived from the opium poppy (Papaver somniferum) and is a centrally acting antitussive opiate derivative. It is a non-competitive antagonist of the bradykinin B2 receptor. It also exhibits neuroprotection by activating sigma-1 opioid receptors, which help suppress intracellular NO levels and calcium, thereby providing protection against ischemic injury.