Guide · Food and modes · 3 min read
Fasting in Ramadan on a GLP-1 medicine
This article follows the IDF-DAR guidelines on diabetes and Ramadan, which are written for people with diabetes, so if you take the medicine for weight, ask your doctor how they apply to you. 1 The Ramadan studies were done mostly with liraglutide, lixisenatide and exenatide, and the guidelines say more research is needed on newer medicines. 1 On their own these medicines carry a low risk of severe low blood sugar, but the risk may be higher with a sulphonylurea or insulin. 1
Talk to your doctor early
The guidelines advise a visit ideally 6 to 8 weeks before Ramadan. 1 There your doctor looks at whether fasting is safe for you and how to adjust your medicines. 1
Your dose
- Finish dose increases before Ramadan. The guidelines say that when the dose has been adjusted at least 2 to 4 weeks before Ramadan, no further changes are needed. 1
- Weekly injection: you can have it at any time of day, and you can change the day as long as at least 3 days have passed since your last injection. 3·4
- Tablet: ask your doctor which meal to fit it to; semaglutide tablets are taken after not eating for at least 8 hours, and you wait at least 30 minutes before eating or drinking. 3
Does the injection break the fast?
The International Islamic Fiqh Academy ruled that injections under the skin, into a muscle or into a vein do not invalidate the fast, except nutritive fluids. 2 It also asks doctors to move such treatments to after iftar when the delay does no harm. 2 The diabetes guidelines say the same for insulin injections. 1
Suhoor and iftar
- Have suhoor as late as possible, with enough protein and fat. 1
- Start iftar with plenty of water and 1 to 3 small dates. 1
- Drink water and unsweetened drinks between iftar and suhoor; keep coffee, tea and cola low, as they can lead to dehydration. 1
- Avoid sugary drinks and sweet desserts after iftar. 1
- Keep meals small: vomiting is more likely after a large meal. 5
When to break the fast
- Break the fast if you have signs of low or high blood sugar, dehydration or a sudden illness. 1
- If you check your blood sugar, break the fast when it is below 70 mg/dL (3.9 mmol/L) or above 300 mg/dL (16.6 mmol/L). 1 Check again within 1 hour if it is between 70 and 90 mg/dL. 1
- Signs of low blood sugar include trembling, sweating, a racing heart, hunger, confusion and headache. 1 Take a small amount of fast-acting sugar, such as a small carton of juice, and check again after 15 to 20 minutes. 1
In CalJab
The Ramadan card in Guide counts down the days to Ramadan. You can change your dose day and time on your medicine's page in Health, and your reminder follows. Your doctor report puts your doses, symptoms and weight together for the visit before Ramadan. During Ramadan, if you turn on "I'm fasting this Ramadan" in Reminders, no sips or lunch reminder comes during the day.
Plan your fasting with your doctor; for religious questions, ask a scholar you trust.
Sources
- 1International Diabetes Federation and DAR International Alliance. Diabetes and Ramadan: Practical Guidelines 2021. media.idf.org
- 2International Islamic Fiqh Academy. Resolution No. 93 (1/10): Invalidators of fasting in medical treatments. Jeddah, 1997. iifa-aifi.org
- 3NHS: Semaglutide. Last reviewed 15 May 2026. nhs.uk
- 4NHS: Tirzepatide. Last reviewed 15 May 2026. nhs.uk
- 5Mozaffarian D, et al. Nutritional priorities to support GLP-1 therapy for obesity: a joint Advisory from ACLM, ASN, OMA and The Obesity Society. Obesity 2025;33(8):1475-1503. pmc.ncbi.nlm.nih.gov
Written by the CalJab team, with sources. It does not replace your doctor's advice. Found a mistake? Write to support@caljab.app.