What to drink on a GLP-1: water, electrolytes, coffee and fizzy drinks

When a GLP-1 turns your appetite down, drinks can quietly slip off the list too. This guide covers how much fluid you need, what to reach for on ordinary days and harder ones, and where coffee, fizzy drinks and protein drinks fit. Questions about your dose or other medicines are for your prescriber.

Why do fluids matter so much on a GLP-1?

Because stomach side effects can drain your fluids, and the labels link that fluid loss to kidney problems.

The Ozempic and Mounjaro Medication Guides say it plainly: diarrhea, nausea and vomiting may cause a loss of fluids (dehydration), which may cause kidney problems. They say drinking fluids helps reduce the chance, and to tell your healthcare provider right away if nausea, vomiting or diarrhea doesn’t go away.

There’s a quieter reason too. A 2022 expert consensus on GLP-1 side effects notes that feeling full after the medicine can lead people to drink less water. Eating less also means less water from food.

How much should you drink in a day?

There’s no single number, but a National Academies panel set adequate intakes of about 2.7 liters (91 oz) a day for women and 3.7 liters (125 oz) for men, counting all drinks and food.

A few things make that number easier to read:

• It’s total water. About 80% comes from drinks, including coffee and tea, and about 20% from food.
• It’s not a rule of glasses. The panel chose not to give a glasses-per-day rule, and said most people meet their needs through normal drinking and by letting thirst guide them.
• Some people need more. Very active people and those in hot climates may need more.

On a GLP-1, eating less food means less water from your plate, so drinks may need to do more of the work. Water-rich foods like soup, yogurt and fruit count as well.

What’s the best everyday drink?

Water, still or sparkling, plus other unsweetened drinks.

The Dietary Guidelines for Americans 2025–2030 say to choose water (still or sparkling) and unsweetened beverages, and to avoid sugar-sweetened drinks like sodas, fruit drinks and energy drinks. The 2025 joint advisory on GLP-1 nutrition also lists sugar-sweetened beverages among things to minimize.

How you drink can matter as much as what. The 2022 consensus suggests clear, fresh drinks in small sips, but not so much at once that you feel too full. It also suggests not drinking through a straw.

When do electrolyte drinks help?

They help most on days you’re losing fluid through vomiting or diarrhea.

The NIDDK says that with diarrhea you need to replace both fluids and electrolytes. It suggests water plus liquids that contain electrolytes, such as broths and sports drinks, or oral rehydration solutions. Those are drinks with glucose and electrolytes, sold where medicines or baby supplies are sold.

One important caveat from the same page: older adults, people with a weak immune system, and people with diabetes, kidney disease or other health conditions should talk with their doctor before drinking oral rehydration solutions. Many people on a GLP-1 have type 2 diabetes, so this is worth asking about before you need it.

On ordinary days, plain water is usually enough. More on harder days in gentle meals for queasy days.

Can you drink coffee on Ozempic or another GLP-1?

The labels don’t mention coffee or caffeine, and for most adults the FDA says about 400 mg of caffeine a day isn’t generally linked to negative effects.

The FDA puts 400 mg at about two to three 12 oz cups of coffee. It also says people vary a lot in how sensitive they are to caffeine. Certain conditions and medicines can make you more sensitive, so ask your provider if you’re unsure, or if you’re pregnant, trying to become pregnant or breastfeeding.

If your stomach is unsettled, the 2022 consensus suggests going easy on coffee, tea and cola. It suggests avoiding them when heartburn is a problem, and avoiding coffee when you have diarrhea. A smaller cup, or one with milk after food, can feel kinder.

Are fizzy drinks okay?

Plain sparkling water fits the guidelines, but bubbles don’t suit every stomach on a GLP-1.

The 2022 consensus suggests avoiding carbonated drinks if you have reflux, and soft drinks if you have diarrhea. Some people find bubbles add to the full feeling. If that’s you, let sparkling water go a little flat, or switch to still water for a few days. The foods that can feel harder guide has more swaps.

Do protein drinks count?

They count toward your fluids and can help you reach your protein on days when a full meal feels like too much.

The 2025 joint advisory says some people meet their protein targets with high-protein shakes, bars and other fortified products, alongside foods like fish, eggs and Greek yogurt. A milky smoothie or a glass of milk also does both jobs. If a thick drink feels heavy, try a smaller glass sipped slowly.

How to choose one by its label is in the protein shakes guide, and the protein guide covers how much you need.

How does Imi help?

Imi keeps drinks in view alongside your food.

• Water and protein first. Both targets sit at the top of every day.
• Quick logging. Log meals by photo, barcode, text or voice.
• Gentler days. Log nausea and Imi plans lighter meals.
• Grocery list by aisle. Your week’s plan turns into one list, sorted the way you shop.

Imi helps with food. Your prescriber handles your medication. Ready to shop? Build your grocery list.

Ozempic and Wegovy are trademarks of Novo Nordisk A/S. Mounjaro and Zepbound are trademarks of Eli Lilly and Company. Imi isn’t affiliated with either company.