Preparations for APD testing: Your child should be well rested and should have eaten a regular meal/snack before the appointment. If your child is not feeling well or is tired, please call the office and reschedule.Testing can take up to 90 minutes, although there are breaks in between individual tests. If your child takes medication for ADD or AD/HD they must take their medication as usual. Not taking medication as prescribed will interfere with accurate test results. If prescribed medication is not taken as directed before the test, your child will be rescheduled and charged a rescheduling fee of $150.