What to eat when you feel sick on GLP-1 medication

Nausea is a side effect of these medicines, so the first person to ask is your prescriber or pharmacist. What this page can do is list small, plain foods with some protein in them, which many people find easier to face on a low-appetite day.

Updated 9 October 2026 · By the ParrotPal team

Key facts

Feeling sick is a known side effect of GLP-1 medicines; your prescriber, GP or pharmacist can advise on it. ParrotPal doesn’t give treatment advice. On days when a full meal is too much, small portions of protein foods such as skyr, cottage cheese, eggs or a protein milk keep some protein coming in.

Talk to your prescriber first

If you feel sick on Mounjaro, Wegovy, Ozempic or Zepbound, tell your prescriber or pharmacist. They can look at your medicine and your situation. If you can’t keep food or fluids down, or you feel very unwell, contact them, your GP or NHS 111 straight away.

Small, plain protein ideas

When you can’t face a meal

Protein

• A pot of skyr or 0% Greek yogurtabout 15 to 17 g
• 150 g of cottage cheeseabout 15 g
• A ready-to-drink protein shake or protein milkabout 15 to 20 g
• Two boiled eggs and a glass of milkabout 15 to 20 g

Approximate, from typical UK supermarket labels. Brands vary, so check the packet.

How to fit them in

• Small and often. Many people find smaller, less greasy meals easier. Four small sittings can be easier than three meals.
• Protein first. If you only manage a few mouthfuls, make them the protein.
• Keep it simple. Plain foods you already like are a good place to start.

For a week of small, protein-first meals, see the 7-day Mounjaro meal plan. For drinks and shakes, see protein shakes on Mounjaro.

Why protein still matters on low-appetite days

When you eat much less, some of the weight you lose is lean mass, muscle included. Enough protein and some strength work are the habits linked to keeping more of it: see muscle loss on Mounjaro. Our protein calculator gives you a number to aim for over the week.

What the research says

• A 2025 joint advisory from four US nutrition and obesity societies notes that higher protein targets, such as 1.2–1.6 g per kg a day, have been proposed during active weight reduction (or an absolute 80–120 g a day), and that protein intake in adults should not fall below 0.4–0.5 g per kg a day.

  Mozaffarian D, Agarwal M, Aggarwal M, et al. (2025). Nutritional priorities to support GLP-1 therapy for obesity: a joint advisory from the American College of Lifestyle Medicine, the American Society for Nutrition, the Obesity Medicine Association, and The Obesity Society. Obesity 33(8):1475–1503. doi:10.1002/oby.24336

• In the STEP 1 trial, body scans in a substudy found lean mass made up about 4 in every 10 kilos lost (5.3 kg of 13.6 kg). Lean mass includes muscle, organs and water.

  Wilding JPH, Batterham RL, Calanna S, et al. (2021). Once-weekly semaglutide in adults with overweight or obesity. New England Journal of Medicine 384(11):989–1002. doi:10.1056/NEJMoa2032183

Research describes the people who were studied. Where we quote our own members’ figures, they are what members logged, and the method is on our methodology page.

Questions people ask

Related guides and data

• GLP-1 nutrition: all our guides and data
• GLP-1 diet plan
• Foods to limit on Mounjaro
• Protein shakes on Mounjaro