What is the best treatment for clear runny nose in 3 yr old?

Runny nose: If it is a cold it will clear in its own with time. If it is allergy related, claritin, (loratadine) zytec or Allegra may help. Talk to your doctor about dosing on medication.

Depends: Clear runny nose (called rhinorrhea) can be related to a cold in which case it will resolve on it's own within 7-10 days. Prolonged clear runny nose could be an allergy. If that's the case, it should respond well to a new generation antihistamine such as zyrtec, Claritin (loratadine) or allegra. Each of these comes as a syrup. If it doesn't respond, a physician can assist in evaluation and treatment.