Well, atarax usually does not cause any change in blood count
, but an allergic reaction can.
Do discuss this with your doctor and assess whether dehydration is the cause for higher Hb. Normal values of hemoglobin in adults is 12 to 18 grams per deciliter (may vary from lab to lab). So, it is still within normal limits. Hemoglobin levels increase in severe dehydration, polycythemia vera, heart failure, Congenital heart disease, cor pulmonale, smoking, lung fibrosis etc.