My 4 year old has many symptoms of allergies, but blood test come back normal. She is miserable and can't sleep. Claritin (loratadine) doesn't help. What next?

Environmental. One of the most common aggravating factors leading to drainage in young kids is their inhaled exposures. Dust, fragrance, hair spray, plug ins, scented soaps, etc. Anything you can smell can make them drain. I'd start with their sleeping area. They spend more time there & it is more controllable. Particle filters help. Consider the house next if there is no improvement.
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