 [ Symptoms ] my 10 year old weighs around 100 pounds she has severe allergies what allergy medications can she take [ Disease ] there are several options available over the counter to treat allergy symptoms for a 10 year old loratadine and cetirizine are the two newest otc antihistamines available the advantage to these medications is that they work for a full 24 hours and you only need to take them once a day cetirizine found in zyrtec tends to cause a bit more drowsiness than loratadine which is found in claritin you should talk to your daughter is pediatrician if she is having severe allergies to ensure an over the counter antihistamine is appropriate for her at this time