H1blocker with least sedative effect is -
Ans. is 'c' i.e., Terfanadine Terfanadine is a second generation antihistaminics. Advantages of second generation Antihistaminics. o Higher H1 selectivity, no anticholinergic side effects. o Absence of CNS depressant propey o Additional antiallergic mechanism apa from histamine block. o No impairment of psychomotor performance (driving etc. need not be contraindicated) o No subjective effect, No sleepiness. (Some patients complain of sedation, but the incidence is similar to placebo) o Do not potentiate alcohol or benzodiazepene
Chlorpheniramine
Promethazine
Terfenadine
Diphenhydramine