We do not want our 17 ohp in the normal range. 81 is low. Between 300 to 1000ng/dl is better um especially 10 hours after the last dose was given. I’m not a doc but if I were you I would get another doc, especially if they have you set up to come in 6 months. Most small children see their docs every 3 months. My daughter is 14 and she finally graduated to 4 months!