Jabwise

Drinking enough when you feel sick

Being sick and diarrhoea can dehydrate you, as every leaflet and label here says. Mounjaro’s says drink plenty of fluids; Wegovy’s and Ozempic’s add this is especially important with kidney problems. None gives an amount. Zepbound’s label says tell your healthcare provider right away if it doesn’t go away.

In their own words

Why each leaflet raises it, and what it asks you to do, quoted as written.

MedicineWhyWhat to do
MounjaroWhen starting treatment with Mounjaro, in some cases you may experience loss of fluids/dehydration, e.g. due to vomiting, nausea and/or diarrhoea, which may lead to a decrease in kidney function.Mounjaro KwikPen patient leafletIt is important to avoid dehydration by drinking plenty of fluids.Mounjaro KwikPen patient leaflet
ZepboundDiarrhea, nausea, and vomiting may cause a loss of fluids (dehydration) which may cause kidney problems.Zepbound prescribing informationIt is important for you to drink fluids to help reduce your chance of dehydration.Zepbound prescribing information
WegovyThese side effects can cause dehydration (loss of fluids).Wegovy FlexTouch patient leafletIt is important that you drink enough fluids to prevent dehydration.Wegovy FlexTouch patient leaflet
OzempicThese side effects can cause dehydration (loss of fluids).Ozempic patient leafletIt is important that you drink plenty of fluids to prevent dehydration.Ozempic patient leaflet

What else they say

  • Early on

    Mounjaro’s leaflet says that, in some cases, fluids can be lost when you start treatment, through sickness or diarrhoea.

  • Kidney problems

    Wegovy and Ozempic say drinking enough fluids to avoid dehydration matters especially if you have kidney problems.

  • When it won’t stop

    Zepbound’s label says tell your healthcare provider right away about nausea, vomiting or diarrhoea that does not go away.

  • No set amount

    None of the leaflets, nor Zepbound’s label, gives a set number of glasses or litres to drink. A pharmacist can help.

Questions

How much should I drink?

The leaflets don’t give an amount. Mounjaro’s and Ozempic’s say plenty of fluids, and Wegovy’s says enough. A pharmacist can help if you’re not sure.

Does it have to be water?

The leaflets say fluids, not water in particular. On alcohol, the NHS says it can increase side effects like feeling or being sick, so it’s best not to drink it.

When should I get help?

The NHS says to speak to a pharmacist or doctor if you have side effects that bother you or do not go away. Zepbound’s label says tell your healthcare provider right away if nausea, vomiting or diarrhoea does not go away.

Water and steps

Jabwise counts every glass.

Tap the plus on the water pill to log a glass or a bottle. Water shows today against a goal you set, your streak and the last two weeks, and water from Apple Health counts too if you connect it.

Jabwise Water: 1 litre today, half of a 2 litre goal, a five-day streak and bars for the last two weeks

Sources

General information, not medical advice. Follow your prescriber’s guidance.

Getting real advice

We’re not doctors. This page sums up what the NHS and the official medicine information say, and can’t tell you what’s right for your body: your prescriber’s instructions and the leaflet in your box come first. More in our terms.

  • Quoted from official sources, each one linked
  • Sources checked 12 October 2026
  • No dosing advice; your prescriber comes first