Ramadan Fasting Guide for Oncology patients

Is Fasting Allowed?
Your health comes first.
There is no single answer for all oncology patients. According to the Emirates Oncology Society, fasting decisions must be individualized. So please discuss with your physician if you're allowed to start fasting or not.
Why Fasting Can Be Risky for Oncology Patients
- Cancer treatment can cause weakness and dehydration.
- Some medicines must be taken with food or at fixed times.
- Not drinking enough fluids can harm the kidneys.
- Nausea, vomiting, dizziness, and fatigue may get worse.
Who Should Not Fast?
- IV chemotherapy days. You may fast on non-treatment days only if your doctor approves.
- If you need IV medication (such as chemotherapy or fluids) or frequent hospital visits.
- If you have strong nausea, vomiting, diarrhea, or cannot eat.
- If you have significant weight loss or dehydration.
- After major cancer surgery (during recovery).
- During intensive/long radiotherapy if dehydration or fatigue develops.
Who May Be Allowed to Fast (Only with Doctor Approval)?
- You are medically stable.
- Your treatment is mild or oral and can be safely scheduled at night.
- You can drink enough fluids between Iftar and Suhoor.
- Your oncology team clearly approves fasting.
STOP Fasting Immediately and Get Help If You Have
- Dizziness or fainting.
- Severe weakness.
- Vomiting or diarrhea.
- Very dry mouth or little urine.
- Chest pain or breathing problems.
- Missed or vomited cancer medicines.
Call your oncology team or go to emergency care.
Medications & Fasting
- Do NOT stop or change medicines by yourself.
- Some cancer medicines must be taken with food or at exact times.
- Oral cancer medicines may be taken after Iftar if timing is safe. Ask your oncology pharmacist.
- Twice-daily oral medicines need at least 9–10 hours between doses (often at Iftar and Suhoor).
- If safe timing is not possible, fasting may not be safe.
- Your doctor may prescribe anti-nausea patches (up to one week) to reduce the need for oral medicines after chemotherapy.
If you miss a dose: do NOT double the dose. Call your doctor or pharmacist.
Eating & Drinking Safely During Ramadan
Nutrition Dense Food
| Proteins | Carbohydrates | Healthy Fats |
|---|---|---|
| Such as lean meat; legumes (like fava beans, chickpeas, lentils), dairy products, fish, chicken, and eggs. | Such as rice, pasta, potato, bread, hareese. | Such as olive oil, raw unsalted nuts, avocado, fatty fish. |
Hydration
Drink 1.5–2 liters of fluids between Iftar and Suhoor
| Water | Soup, Milk, Yogurt and Laban | De-caffeinated teas like chamomile, ginger, and anise |
|---|
- Small frequent meals; at least three meals; bland foods, avoid strong smells to prevent nausea.
- Fluids and fibers (vegetables, legumes, whole grains, unsalted nuts, and dried fruits) to avoid constipation.
- Limit caffeinated tea, coffee, and soft drinks.
- Limit salty and ultra processed food, spicy and deep-fried food.
Family & Emotional Support
- Families should respect the patient's decision if fasting is medically approved.
- Avoid stress and avoid medical advice from social media.
Key Messages
- Your health comes first.
- Many cancer patients are exempted from fasting.
- Fasting decision must be personal.
- Always speak to your oncology team before Ramadan.
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