My ten year old has seasonal allergies for the first time. i gave her 24 hr claritin (loratadine) at 7:30 am. it's 9pm. can i give her children's diphenhydramine?

Yes: 10 year old with seasonal allergies, got claritin this morning. Yes, it is safe to give her children's benadryl (diphenhydramine) before bedtime. However, benadryl (diphenhydramine) only lasts a few hours and causes drowsiness, should not be given on a regular basis. There are other treatments for allergies. Get her checked out by pediatrician to make sure her symptoms are consistent with allergies, and for more treatment options.

Okay: This is fine for short or longer term treatment. You might consider some of the newly made OTC nasal sprays with a low dose steroid (Nasocort,Rhinocort,etc.)I find many young women don't like the sprays, but if they will give them a week or two the allergies get better and they can sometimes drop the pills.