Diarrhea on a GLP-1: what to eat and drink to feel steadier

Diarrhea is one of the side effects people talk about least and live with most on a GLP-1. The good news is that food and drink can help you feel steadier while your body adjusts. This guide covers how common it is, what to drink, what tends to sit well and what to go easy on, and when to call for help. Questions about your dose or anti-diarrhea medicine are for your prescriber or pharmacist.

Is diarrhea common on a GLP-1?

Yes. Diarrhea is listed among the most common side effects on GLP-1 labels.

Here’s how often it was reported in the clinical trials, as the labels state it:

• Wegovy 2.4 mg injection (adults, weight reduction). 30% of people, compared with 16% on placebo.
• Zepbound (adults, weight reduction). 19% to 23% depending on dose, compared with 8% on placebo.
• Mounjaro (adults with type 2 diabetes). 12% to 17% depending on dose, compared with 9% on placebo.

The Mounjaro and Zepbound labels say most nausea, vomiting and diarrhea happened while the dose was being stepped up, and decreased over time. A 2022 expert consensus adds that diarrhea usually starts in the first four weeks, and that in people with obesity it has been reported to last about three days.

What should you drink when you have diarrhea?

Drink more than usual, and include drinks with electrolytes, because diarrhea drains both water and salts.

• Keep up with losses. MedlinePlus suggests at least 1 cup (240 ml) of liquid every time you have a loose stool.
• Add electrolytes. The NIDDK suggests water plus liquids with electrolytes, such as broths and sports drinks, or oral rehydration solutions.
• Ask first if you have diabetes or kidney disease. The NIDDK says older adults and people with diabetes, kidney disease or other health conditions should talk with their doctor before using oral rehydration solutions. There may be a better option or amount for you.
• Sip, don’t gulp. On a GLP-1, small sips through the day are often easier than large glasses.

The labels give the reason this matters. The Wegovy Medication Guide says diarrhea, nausea and vomiting may cause fluid loss that may lead to kidney problems, and that drinking fluids helps lower the chance. More in what to drink on a GLP-1.

What foods are easier to eat?

Plain, lower-fat, cooked foods in small portions tend to sit best.

MedlinePlus lists foods that are generally okay when you have diarrhea, including baked or broiled chicken, fish or turkey, cooked eggs, white rice, pasta, bread made from white flour, oatmeal and cooked vegetables like carrots and peeled zucchini. It also suggests high-potassium foods like bananas and potatoes, and some salty foods like soup. Check with your provider about potassium if you have significant chronic kidney disease.

The 2022 GLP-1 consensus names chicken broth, rice, carrots and very ripe fruit without the skin. Small meals through the day are easier than three large ones, which MedlinePlus suggests too.

Protein still matters on these days. Eggs, fish and chicken are some of the gentlest ways to get it. The protein finder can help you find more.

What foods can make diarrhea worse?

Greasy food, very sweet food and drinks, sugar-free sweets, caffeine and alcohol are the usual ones.

The NIDDK suggests avoiding these during short-term diarrhea:

• High-fat foods like fried food, pizza and fast food.
• Lots of simple sugars, as in sweetened drinks, some fruit juices, candy and packaged desserts.
• Sugar alcohols, found in sugarless gum and candy. The consensus names the ones ending in “-ol”, like sorbitol, xylitol and maltitol.
• Caffeine, as in coffee, tea and some soft drinks.
• Alcohol.
• Milk products with lactose, if they make it worse. The NIDDK says some people have trouble digesting lactose for a month or more after acute diarrhea.

MedlinePlus adds gassy foods like beans, broccoli and corn, and carbonated drinks. None of this is forever. The foods that can feel harder guide has swaps for when you’re ready.

Should you follow the BRAT diet?

You don’t need to. Bananas, rice, applesauce and toast are fine to eat, but current guidance doesn’t call for eating only those.

The NIDDK says most experts don’t recommend a restricted diet, beyond avoiding the foods above, or fasting when you have short-term diarrhea. It says that when your appetite comes back, you can usually return to your normal diet, even if you still have diarrhea. Use BRAT foods as a starting point, then add eggs, chicken, fish, yogurt if it suits you, and cooked vegetables to keep protein and nutrients coming in.

Does fiber help or hurt?

It depends on the fiber. Softer foods like oatmeal and bananas usually sit well, while lots of rough fiber can be harder for a few days.

The 2022 consensus suggests temporarily cutting back on high-fiber foods such as whole-grain bread, nuts, seeds, beans and lentils, and fruits with skins. MedlinePlus suggests asking your provider whether a fiber supplement could add bulk to your stools. If you’ve been working on fiber for constipation, you can build it back up once things settle. See constipation and fiber.

When should you call your care team?

Call if diarrhea won’t go away, is severe, or comes with signs of dehydration or other warning signs.

The GLP-1 Medication Guides ask you to tell your healthcare provider right away if nausea, vomiting or diarrhea doesn’t go away. The NIDDK lists signs of dehydration to watch for:

• extreme thirst or a dry mouth
• urinating less than usual, or dark urine
• feeling tired, dizzy or lightheaded
• sunken eyes or cheeks

How does Imi help?

Imi takes care of the food side while things settle.

• Side-effect check-ins. Track side effects in a tap. When you log nausea, Imi plans gentler meals.
• Easy swaps. Ask Imi to “make dinner gentler” and it swaps the meal for you.
• Water and protein first. Both targets sit at the top of every day.
• Your dose in one place. Log doses and see an estimated level, injection site rotation and your supply.

Imi helps with food. Your prescriber handles your medication. For more on harder days, read gentle meals for queasy days or visit the GLP-1 hub.

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