My son is three years old. He is tall and weighs 37 pounds. He drinks one gallon of fluids per day, every day, including 16 ounces of milk and the rest half water, half apple juice. He uses a sippy cup. He wakes several times during the night for drinks and drinks all day long. He becomes hysterical if you deny him drinks. He will drink to the point of getting a belly ache if you don’t stop him. This is not new behavior; it’s been going on for a long time. His appetite for regular food is fair. He loves sweets and, if he gets them, becomes like a drug addict wanting to consume large amounts. My son is often irritable, but has no other symptoms, no weight loss and otherwise looks and seems healthy. He is very active.

The only history of diabetes is his maternal grandfather who has adult onset. Could this be diabetes? Do I have to be concerned about water intoxication?

You did not indicate other details such as how long this has been going on and, while I doubt there is an emergency here, I think that you should, without much delay, have your son checked by his primary pediatrician. What you described is NOT normal.

It certainly may reflect diabetes mellitus (“sugar diabetes”). But it also could reflect more uncommon conditions, including an entity with the confusing name of “diabetes insipidus” which is a hormonal condition that leads to massive urination and thirst but unrelated to sugar. A complete history and physical examination with some select blood and urine tests often can easily distinguish whether or not there is a worrisome process going on.

Other conditions that impact the blood calcium, the production of cortisol and other hormones from the adrenal glands, and the production of thyroid hormone can also sometimes mimic the symptoms you suggest. Rarely, this reflects a psychologic issue.

Call for an appointment and I would ask that you try to bring the child in FASTING, from about midnight on without food or water to an early morning appointment.

If he also awakens at nighttime to urinate and drink or if you have sometimes seem him drink from odd places to quench his thirst (eg. dog dish), or if he really craves rather COLD drinks over others, I would think about diabetes insipidus.

You may want to print this off to present to your doctor.

Please let us know what you learn but I would not delay.

DS