In my experience ( in a hospital), this seem almost always , accompanied by low Magnesium and Calcium or either. However, if mother is allowed to breastfeed her baby as she should, this seem to alleviate the problem. Last night there was a case where a 2 days old baby displayed signs of jitteriness. The doctor ordered heelstick glucose levels every three hours! some results were borderline and some were low. Of course the dreaded formula was also ordered too . It did,nt help. I had to really insist that the nurse who was taking care of the baby, call the doctor and convince the doctor to order Mag. and Cal. levels instead of continuing to stick the baby,s heel. Sure enough, the Calcium level was very low and the Magnesium borderline, As mentioned before these three important seem to work together when normal, and against each other if something else is going on. Of course I stand corrected if I am wrong. Dr. Newman ( I met you in Orlando in January) please correct me if I am wrong.