Family and Caregiver Schizophrenia Discussion Forum

Changes in eating/drinking habits

With my stepson being newly diagnosed, is it normal for his eating and drinking habits to change drastically? We rarely drink sodas and for the last month since he has been out, he will drink soda non stop. He is also eating a lot more than he use to, like 3 or 4 full meals and a lot of snacks in between.

Many atypical AP medications affect appetite, some more than others. Weight gain as a result of blood sugar and other changes is common. It tends to level off over time, but can be quite pronounced initially with certain medications. I experienced this initially with Olanzapine and gained 20 pounds quickly. My girlfriend at the time remarked she couldn’t keep enough food in the house for the first few months when I switched to it.

I’ve experienced excessive drinking known as Psychogenic polydipsia as well. It’s not clear if this is an attempt to counteract side effects of dry mouth and sedation, as I tend to drink coffee and caffeinated soda semi compulsively. Some of this behavior goes back to before I was diagnosed. I’ve described the experience as being habituated to having a certain feeling of liquid in my mouth. I’ve had people comment on it at work, as I’m frequently found with a coffee cup or Diet Coke can in hand and misplaced mugs and cans litter my wake. Like many of my symptoms, workmates tend to view it as an endearing quirk of “mad genius” — little do they know.

I’m thankfully free from the compulsive cigarette smoking habit many diagnosed people have, and I have had periods of abstinence from caffeine, but it’s generally easier to replace a habit with another habit, so I usually switch to drinking water. The logistics of my Diet Coke drinking habit are burdensome, keeping the supply chain going and recycling the cans is not an insignificant endeavor. On bad days I drink about a 12 pack a day.

Yes, eating and drinking habits can change drastically. Other usual activities can suddenly change also.

My son stopped eating almost completely and drank very little for a few days. It might have been the result of a rapid up-titration of quetiapine to 800 mg, or it could have been his psychosis, as in command voices telling him not to eat or drink.

It resolved in a week or so. The lack of drinking was particularly worrisome, so my wife and I encouraged him to drink.

Eating is back to normal, the addition of olanzapine probably having something to do with it. He might now have the psychogenic polydipsia which @Maggotbrane referred to. He drinks about a gallon of liquids a day. One wouldn’t think that would matter, except that it can lead to an electrolyte imbalance (hyponatremia).

My son says he drinks not because he’s thirsty but because it relieves anxiety, so he might have psychogenic polydipsia.

How much is too much water?

Severe Hyponatremia in a Schizophrenic Patient says:

  • Healthy patients on a normal diet may consume up to 20 L of water per day before they develop hyponatremia.

So one might think it would never be a problem for young, healthy people.