<prompt> An unknown patient presents with pyrexia, constricted pupils, hypotension, cyanosis and stupor progressing to coma. Poisoning is due to -PhenobarbitoneCannabisDhaturaDiphenhydramine  <response>: Among the given four options, only Phenobarbitone Barbiturate can cause constricted pupils.All the given symptoms can occur in barbiturates phenobarbitone poisoning. 