Promethazine works on histamine-one (H1) receptors. H1 receptors are existing during the bronchial tubes and in the circulatory process. The attachment of histamine to these receptors brings about bronchoconstriction and enhanced vascular permeability, which ends up in plasma leakage. You shouldn't use codeine For those who have intense respiration difficulties, https://buy-codeine47802.blogs-service.com/59622500/the-5-second-trick-for-promethazine-for-sale