Codeine is a selective agonist for the mu opioid receptor, but with a much weaker affinity to this receptor than morphine, a more potent opioid drug. Codeine binds to mu-opioid receptors, which are involved in the transmission of pain throughout the body and central nervous system . The analgesic properties of codeine are thought to arise […]
PAR and Hi-Tech are pharmaceutical manufacturers. They both manufacture promethazine with codeine syrup so the only real significant difference is the taste and colour.PAR promethazine with codeine is a purple syrup and Hi-Tech promethazine with codeine is a red syrup.They both contain the same dose of active ingredients promethazine hydrochloride/codeine phosphate 6.25mg-10mg/5mL syrup.