how long does it take for loratidine to work
Loratadine Loratadine's peak effect occurs after one to two hours, and its biological half-life is on average 8 hours (range 3 to 20 hours) with desloratadine's half-life being 27 hours (range 9 to 92 hours), accounting for its long-lasting effect.[19] About 40% is excreted as conjugated metabolites into the urine, and a similar amount is excreted into the feces. Traces of unmetabolised loratadine can be found in the urine.[8]
Distribution (pharmacology) Highly lipid-soluble drugs given by intravenous or inhalation routes are initially distributed to organs with high blood flow. Later, less vascular but more bulky tissues (such as muscle and fat) take up the drugâ€”plasma concentration falls and the drug is withdrawn from these sites. If the site of action of the drug was in one of the highly perfused organs, redistribution results in termination of the drug action. The greater the lipid solubility of the drug, the faster its redistribution will be. For example, the anaesthetic action of thiopentone is terminated in a few minutes due to redistribution. However, when the same drug is given repeatedly or continuously over long periods, the low-perfusion and high-capacity sites are progressively filled up and the drug becomes longer-acting.