What happens if you mix allegra with zyrtec and claritin (loratadine)?

Allergy meds: Hello. Allergy medication like zyrtec, Allegra and Claritin (loratadine) help with the symptoms of allergy. The dose for an adult is 180 mg for allegra, 10 mg for Claritin (loratadine) and 10 mg for zyrtec. If you take all these meds on the same day, an increase in dryness as well as sedation will likely occur. There are other medications to help with your allergies. See your doctor.