Vomiting: protecting fluids and knowing when to call
Vomiting can cause loss of fluid and salts, weakness and medicines not being absorbed. This section explains how to restore fluids after vomiting, how to return to food and when to call for help at once.
01Short answer
02Simple explanation
Fluids in small sips.
Rehydration solution.
Then soft food.
Vomited a medicine? Ask.
03Scientific explanation
Dehydration: frequent vomiting can cause sodium and potassium loss and worsen kidney function; oral rehydration solutions replace water and salts together.
ESPEN: enough energy and protein matter for preventing weight and muscle loss in people with cancer, and nutritional status should be assessed regularly.
NCI: practical eating tips exist for treatment side effects such as nausea, taste changes and mouth sores.
04What happens in the body?
A gradual return
Clear fluids → broth → rice, potato, biscuits → normal food.
Mouth care
Rinse your mouth with water after vomiting; brush gently with a soft brush a little later.
Dietitian
If you are losing weight, have no appetite or need a special diet, ask to see the hospital dietitian.
Food safety
Food-safety rules for neutropenia (see “Handwashing: the simplest protection” and “Eggs and dairy: safe choices”) apply at every stage.
05Nutrition: four steps
Assess, swap the risky, cook safely, eat regularly.
06Key points at a glance
| Topic | In brief |
|---|---|
 A gradual return | Clear fluids → broth → rice, potato, biscuits → normal food. |
 Mouth care | Rinse your mouth with water after vomiting; brush gently with a soft brush a little later. |
| Dietitian | If you are losing weight, have no appetite or need a special diet, ask to see the hospital dietitian. |
| Food safety | Food-safety rules for neutropenia (see “Handwashing: the simplest protection” and “Eggs and dairy: safe choices”) apply at every stage. |
07Key terms
- Dehydration
- Loss of body water.
- Oral rehydration solution
- A special mix of water, salts and sugar.
- Dietitian
- A nutrition specialist.
- Protein
- A nutrient for repairing muscles and tissues.
- Neutropenia
- Low neutrophils.
08Key points
- Small sips.
- Gradual return to food.
- Call with warning signs.
- A diet is not a treatment.
- Talk to a dietitian.
09Frequently asked questions
I vomited after my medicine; should I take it again?
Not on your own; ask your team.
Do fizzy drinks help?
For some people; let the fizz out and sip slowly.
Can a special diet cure leukemia?
No. Good nutrition helps you cope with treatment, but it does not cure.
10Questions for your doctor
Take these questions to your appointment. The ones you save are collected on the “My questions” page and stay on this device only.
I vomited after my medicine; should I take it again?
Do fizzy drinks help?
Can a special diet cure leukemia?
12Sources
- National Cancer Institute. Eating Hints: Before, During, and After Cancer Treatment
- ESPEN. ESPEN practical guideline: Clinical Nutrition in cancer (2021)
- Leukemia & Lymphoma Society. Food and Nutrition
- World Health Organization. Healthy diet fact sheet
- MedlinePlus (U.S. National Library of Medicine). Iron
- MedlinePlus (U.S. National Library of Medicine). Potassium
- NHS. Vitamins and minerals: Iron
- NHS. Vitamins and minerals: Calcium
- NHS. Vitamins and minerals: Others (magnesium, potassium, zinc, selenium and more)
- NIH Office of Dietary Supplements. Iron — Fact Sheet for Consumers