Ramadan is one of the most spiritually significant times of the year for Muslims across the UK and worldwide. For individuals on a weight loss journey using injectable medications such as Mounjaro (tirzepatide) or Wegovy (semaglutide), the holy month often requires thoughtful planning to balance health needs with fasting.
At Batley Pharmacy, we understand that managing your health and honouring your faith must go hand in hand. This guide is designed to answer all of these questions clearly, drawing on clinical evidence and pharmacist expertise so that you can observe Ramadan with confidence while continuing your weight loss treatment safely.
What Are Mounjaro and Wegovy? Understanding GLP-1 Injections During Ramadan
Both Mounjaro and Wegovy belong to a class of medications known as GLP-1 receptor agonists. GLP-1 (glucagon-like peptide-1) is a naturally occurring hormone in the body that regulates appetite and blood sugar levels.
Mounjaro (tirzepatide), manufactured by Eli Lilly, is a dual-action medication that activates both GIP (glucose-dependent insulinotropic polypeptide) and GLP-1 receptors. This dual mechanism makes it particularly effective at:
- Reducing appetite
- Slowing gastric emptying
- Improving insulin sensitivity
Clinical trials such as the SURMOUNT-1 trial demonstrated that tirzepatide delivered an average weight loss of up to 20.9% of body weight over 72 weeks, making it one of the most effective weight loss medications currently available in the UK.
Wegovy (semaglutide), manufactured by Novo Nordisk, is a GLP-1 receptor agonist that was studied in the extensive STEP clinical trial programme. It works by suppressing appetite, promoting a feeling of fullness, and slowing the movement of food through the digestive system.
Both medications are administered as once-weekly subcutaneous injections, which is an important advantage when it comes to managing them during Ramadan.
Does Mounjaro Break Your Fast?
The widely accepted ruling among Islamic scholars is that subcutaneous injections, meaning injections given under the skin, do not break the fast. For an act to invalidate fasting, it must involve the introduction of a substance into the body through a natural opening, or it must be nutritional in nature.
Subcutaneous injections such as Mounjaro and Wegovy are administered directly into the fatty tissue beneath the skin and do not enter the body through a natural passage. Crucially, they do not provide any caloric or nutritional value to the body.
It is worth noting that Islam also makes explicit provision for those who are unwell or managing a chronic condition. Your health should always come first, and you should speak with both your pharmacist and your religious advisor if you have any doubts.
Is it Safe to Use Mounjaro or Wegovy During Ramadan?
For the majority of people, continuing Mounjaro or Wegovy during Ramadan is safe, but it does require informed planning.
Dehydration Risk with Mounjaro and Wegovy While Fasting
One of the most significant concerns when using GLP-1 injections during Ramadan is dehydration. Both Mounjaro and Wegovy can reduce your sense of thirst, which is already a recognised side effect of these medications.
When combined with fasting hours that can extend from approximately 4 am to 9 pm during UK spring and summer months, this reduced thirst response potentially leads to dehydration, headaches, dizziness, and fatigue. Clinical guidance consistently recommends aiming for 2 to 3 litres of water between Iftar and Suhoor.
Hypoglycemia Risk While Fasting on GLP-1 Medications
GLP-1 receptor agonists like Mounjaro and Wegovy have a low risk of causing hypoglycemia on their own because they work in a glucose-dependent manner. This means they stimulate insulin release only when blood sugar is already elevated.
However, the risk increases significantly if you are also taking other diabetes medications or insulin alongside your GLP-1 injection. If this applies to you, regular blood glucose monitoring during Ramadan is strongly advisable, and you should discuss potential dose adjustments with your GP or pharmacist before the month begins.
Managing Nausea and Gastrointestinal Side Effects While Fasting
Nausea, bloating, and changes in appetite are among the most commonly reported side effects of both Mounjaro and Wegovy. These can be amplified during Ramadan, particularly after Iftar, when people may be eating larger meals than usual after a long day of fasting.
When to Pause Your Weight Loss Injection During Ramadan?
If you experience severe nausea, persistent vomiting, significant fatigue, or difficulty staying hydrated during non-fasting hours, it may be advisable to pause your treatment for the month of Ramadan. Stopping for four weeks will not undo your weight loss progress.
Since you are fasting, significant weight gain is unlikely. When restarting, those who were on a dose of 10mg or higher of Mounjaro should restart at 5mg; those on lower doses may restart at their previous dose. Always consult your prescriber before making this decision.
Best Time to Inject Mounjaro & Wegovy During Ramadan: Suhoor or Iftar?
After Iftar (Recommended)
Taking your injection approximately 30 minutes after breaking your fast, during or just after the Maghrib prayer window, is generally considered the best approach. Food intake at Iftar helps buffer gastrointestinal side effects and significantly reduces the risk of nausea on an empty stomach. The Maghrib prayer window provides a natural pause between breaking your fast and your main Iftar meal, which can be an ideal moment for your injection.
After Suhoor (Alternative)
Some clinicians suggest injecting after Suhoor if you are more likely to experience nausea at night or if you prefer to manage any side effects earlier in the eating window. However, injecting close to the start of a long fast can increase the risk of nausea and appetite suppression that interferes with adequate hydration and nutrition during the eating window.
Research involving GLP-1 receptor agonists broadly suggests that injecting after breaking the fast at Iftar is the most well-tolerated approach for the majority of patients during Ramadan fasting. Because Mounjaro and Wegovy are once-weekly injections, you have considerable flexibility in choosing a consistent day and time that works around your Ramadan routine.
Clinical Evidence for GLP-1 Injections During Ramadan
The use of GLP-1 receptor agonists during Ramadan has been the subject of growing clinical research, particularly because these medications were originally developed for type 2 diabetes management.
A comprehensive systematic review and meta-analysis published in 2025 evaluated the safety and efficacy of GLP-1 receptor agonists in patients with type 2 diabetes fasting during Ramadan. The review found that GLP-1 receptor agonists achieved a greater reduction in HbA1c compared to non-GLP-1 medications, with a significantly lower risk of symptomatic hypoglycemia.
For Mounjaro (tirzepatide) specifically, a prospective, multicentre real-world study published in 2025 examined 109 patients with type 2 diabetes who fasted during Ramadan while taking tirzepatide. The study found that tirzepatide was safe and effective during the fasting month, with improvements in glycemic parameters and weight providing important reassurance for patients considering continuing their treatment during the holy month.
The landmark SURMOUNT-5 phase 3 trial compared tirzepatide and semaglutide head-to-head over 72 weeks in people with obesity. Tirzepatide delivered a mean weight loss of 20.2% compared to 13.7% with semaglutide. Both medications showed primarily mild to moderate gastrointestinal side effects, predominantly during dose escalation, which is important context when planning use during Ramadan.
Managing Wegovy Side Effects While Fasting
Taking Wegovy while fasting may require small adjustments to manage side effects and maintain comfort throughout Ramadan.
Nausea and Digestive Discomfort
Nausea is a common side effect and can worsen if you break your fast with heavy or fried foods. Start Iftar with light options like dates, water, and soup before moving to a main meal. Avoid fatty, sugary, and processed foods to help reduce discomfort.
Reduced Appetite at Suhoor
Wegovy can suppress appetite, making it harder to eat enough at Suhoor. Focus on nutrient-dense foods like oats, eggs, yoghurt, and healthy fats. These provide sustained energy without needing large portions.
Constipation and Bloating
Slower digestion and reduced fluid intake can lead to constipation during Ramadan. Include fibre-rich foods like fruits, vegetables, and wholegrains in your meals. Stay well hydrated and add light movement, such as a short walk after Iftar, to support digestion.
Exercise While Fasting on Mounjaro or Wegovy During Ramadan
Staying physically active during Ramadan supports your weight loss goals and overall well-being, but exercise requires careful consideration when combined with GLP-1 medications and extended fasting hours.
The best time to exercise is approximately two hours after Iftar, when your energy and fluid levels have been replenished. This window allows your body to have fuel available for activity without the risk of hypoglycemia or dehydration that comes with exercising in a fasted state.
Opt for moderate-intensity activities, such as brisk walking, light yoga, or gentle swimming, rather than high-intensity workouts, particularly in the first week of Ramadan, as your body adjusts to the new routine. If you choose to exercise during the day while fasting, keep it light and short, such as a 20-minute walk in the cooler part of the day. Stop immediately if you feel dizzy, faint, or unwell.
What If You Want to Pause Your Weight Loss Injection During Ramadan?
Taking Wegovy while fasting or continuing with Mounjaro during Ramadan is entirely your personal choice. Some people find managing both the fast and the medication straightforward; others find it too challenging and prefer to pause for the month. Both decisions are medically acceptable and will not significantly affect your long-term weight loss outcome.
Pausing your GLP-1 injection for four weeks during Ramadan will not undo your weight loss progress. Given that you will be fasting for the majority of the month, weight gain is unlikely. Evidence has consistently shown that Ramadan fasting in individuals with overweight or obesity is associated with a reduction in body fat percentage.
If you do pause your treatment and then restart after Eid, please be aware that you may need to restart at a lower dose to allow your body to readjust to the medication. If you were taking Mounjaro at 10mg or higher before Ramadan, you should restart at 5mg. If you were on a lower dose, restart at 2.5mg. For Wegovy, consult your prescriber as the recommended restart dose will depend on your individual history with the medication.
Always speak to your pharmacist or prescriber before pausing or restarting your medication. Do not attempt to self-adjust your dose without professional guidance.
Pre-Ramadan Checklist: How to Use Weight Loss Injections During Ramadan
Preparation is key to staying safe, healthy, and confident while fasting on weight loss injections. Use this checklist in the weeks leading up to Ramadan.
Consult Your Pharmacist or GP
Speak to your pharmacist or GP to review your current dose and ensure it is suitable for fasting. If you need personalised support, Batley Pharmacy offers in-person weight loss consultations to help you prepare safely for Ramadan. This allows you to adjust your plan based on your health needs and routine.
Plan Meals in Advance
A well-structured Suhoor and Iftar can help maintain energy levels and reduce side effects. Focus on balanced meals with protein, fibre, and healthy fats to support satiety and hydration. Planning also helps you avoid heavy or processed foods that may worsen symptoms.
Choose the Right Injection Timing
Select a consistent day and time for your injection that fits your fasting schedule. Many people prefer taking it after Iftar when they can eat and hydrate. Sticking to a routine helps minimise side effects and keeps your treatment effective.
Understand Your Body and Warning Signs
Learn to recognise signs of dehydration, hypoglycaemia, or severe side effects. If you are new to fasting on medication, consider a trial fast beforehand to see how your body responds. This helps you make informed decisions during Ramadan.
FAQs
Is it haram to take Mounjaro during Ramadan?
No. Islamic scholars and medical experts broadly agree that subcutaneous injections like Mounjaro do not break the fast because they are non-nutritional and administered under the skin, not through a natural body opening.
Can I use Wegovy while fasting?
Yes, Wegovy can generally be used while fasting with appropriate precautions. Prioritise hydration, choose a post-Iftar injection time, eat balanced Suhoor and Iftar meals, and monitor for side effects. Consult your pharmacist or GP before and during Ramadan for personalised advice suited to your health profile.
Can I take a weight loss injection during Ramadan?
Yes. GLP-1 weight loss injections such as Mounjaro and Wegovy are once-weekly subcutaneous medications that do not break the fast according to the majority of Islamic scholars. Clinical evidence supports their safety during Ramadan with proper planning, hydration, and nutritional management throughout the eating window.
Can I fast while using Mounjaro?
Yes, most people can fast while taking Mounjaro. The once-weekly dosing schedule offers good flexibility, and clinical studies confirm a low hypoglycemia risk when used as a standalone weight loss medication.