Water Intake Calculator
A hydration target tuned for GLP-1 side-effect season.
Daily water target
3liters
In cups (8 oz)
13cups
In fl oz
103oz
GLP-1s blunt thirst as well as hunger, so dehydration sneaks up — and it amplifies nausea, fatigue, and constipation. Sip steadily through the day rather than chugging, which can worsen fullness.
Why hydration is a GLP-1 issue
The same appetite signalling that GLP-1s quiet also dampens your sense of thirst — so many people drift into mild dehydration without noticing. That matters because dehydration amplifies the exact side effects you're trying to avoid: nausea, fatigue, headaches, dizziness, and constipation.
How much to aim for
A practical baseline is around 33 ml per kilogram of body weight per day, adjusted up for activity and hot weather. On days with vomiting or diarrhea you lose fluid and electrolytes faster, so add a buffer and consider an electrolyte drink. The calculator folds all of that into a single daily number in liters, cups, and ounces.
Drinking it in a way that works
Sip steadily through the day rather than gulping large volumes — a full stomach on a GLP-1 fills fast and can worsen that over-full feeling. Keeping a bottle in sight and front-loading fluids earlier in the day both help you hit the target without discomfort.
Frequently asked
- How much water should I drink on a GLP-1?
- A practical target is about 33 ml per kg of body weight per day, plus extra for exercise, heat, or days with nausea and vomiting. Enter your weight above for a personalized number.
- Why am I always dehydrated on Ozempic or Mounjaro?
- GLP-1 medications reduce thirst signals along with hunger, so you feel less prompted to drink even when your body needs fluid. Building a deliberate daily target and sipping steadily counteracts it.
- Can dehydration make GLP-1 side effects worse?
- Yes. Low fluid levels intensify nausea, fatigue, headaches, dizziness, and constipation — several of the most common GLP-1 complaints. Consistent hydration is one of the simplest ways to feel better.
- Should I add electrolytes?
- On days with vomiting, diarrhea, or heavy sweating, an electrolyte drink helps replace what plain water cannot. For ordinary days, water plus a balanced diet is usually enough.
Medical disclaimer. Tiro is a tracking companion, not a medical device, and nothing on this site is medical advice. Always follow the titration schedule and dosing instructions from your prescriber. Never change your dose without talking to them first.