Can you give a child a benadryl (diphenhydramine) after they took claritin?

Yes,: Both are used for allergy. Benadryl (diphenhydramine) is short acting, can be given 3-4 times daily; dose is 5 mg/kg/day, causes some sedation. Claritin is long acting, given once daily. 5 mg once daily below 6 years, 10 mg above 6 and adult, it is non sedating. You can give Benadryl (diphenhydramine) for immediate action even the child has taken claritin. Make sure you don't overdose the child.