Claritin (loratadine) typically starts working within 1 to 3 hours after taking it, with some studies showing onset of action around 75 minutes for symptom relief
. Its peak effect usually occurs after 1 to 2 hours, and the medication can provide relief for about 24 hours
. Claritin-D, which contains loratadine plus a decongestant, may start to work faster, with relief beginning as soon as 30 minutes after the first dose, especially for nasal congestion
. While some people feel symptom relief shortly after the first dose, it can take up to two weeks for Claritin to build up enough in the system to provide consistent allergy symptom control
. In summary:
- Claritin onset: about 1 to 3 hours (average ~75 minutes)
- Claritin peak effect: 1 to 2 hours after dosing
- Claritin-D onset: as soon as 30 minutes for nasal symptoms
- Full consistent relief may take days to two weeks with regular use
This makes Claritin a relatively fast-acting second-generation antihistamine with long-lasting effects and less sedation compared to first-generation antihistamines
