Approximately 4 million Muslims in the UK observe Ramadan each year — fasting from dawn (Fajr) to sunset (Maghrib) for 29-30 days. During the fast, no food or drink (including water) is consumed during daylight hours. In a UK summer Ramadan, this can mean fasting for 18-19 hours per day.
For clinicians in UK primary care, Ramadan creates specific clinical scenarios that require cultural competence, prescribing flexibility, and practical patient guidance. This is not optional knowledge — it is core clinical care for a significant proportion of your patient population.
Who Should and Should Not Fast
Islam exempts from fasting: Individuals who are acutely ill, those with chronic conditions where fasting would cause harm, pregnant or breastfeeding women (if fasting poses risk to mother or baby), menstruating women (who make up missed days later), children before puberty, the elderly who are unable to fast, and travellers. The decision to fast despite a medical condition is ultimately the patient's — your role is to provide clear, evidence-based medical advice about the risks and to support them in making an informed decision, whether they choose to fast or not.
Conditions where fasting is medically inadvisable: Insulin-dependent diabetes (type 1 and type 2 on insulin — high risk of hypoglycaemia during long fasts), poorly controlled type 2 diabetes (risk of hyperglycaemia from medication timing disruption), advanced CKD (dehydration risk in patients with impaired concentrating ability), patients on dialysis, acute illness requiring regular medication or hydration, conditions requiring frequent fluid intake (renal calculi, UTI), and patients on multiple time-critical medications.
The IDF-DAR Practical Guidelines provide a risk stratification framework for diabetic patients who wish to fast during Ramadan — categorising patients as very high risk (must not fast), high risk (should not fast), moderate or low risk (may fast with medical supervision and medication adjustment).
Prescribing Adjustments During Ramadan
The key prescribing challenge: Ramadan shifts the eating window to two meals — Suhoor (pre-dawn) and Iftar (sunset). Medications taken with food must be retimed. Some regimens require dose adjustment.
Twice-daily medications: Usually manageable — take at Suhoor and Iftar. Metformin BD, antihypertensives BD, and most twice-daily antibiotics can be timed to the two meals. Adjust timing so the interval between doses is as close to 12 hours as possible.
Three-times-daily medications: Problematic. TDS regimens cannot be maintained during a fast. Options: switch to a BD or OD equivalent where available (e.g., switch amoxicillin TDS to co-amoxiclav BD, or switch to a once-daily antibiotic where appropriate), or adjust the regimen for the Ramadan period with clear instructions. Discuss with the patient — not all TDS regimens can be safely compressed, and some require specialist advice.
Once-daily medications: Take at Iftar (the evening meal). This is usually straightforward — statins, once-daily antihypertensives, and once-daily PPI can be taken at Iftar without adjustment.
Insulin management (the highest-risk adjustment): Pre-Ramadan assessment is essential. For patients on basal-bolus regimens: the basal insulin dose is usually maintained or reduced by 15-20%, the pre-Suhoor bolus is maintained (for the pre-dawn meal), the Iftar bolus is maintained (for the sunset meal), and the lunchtime bolus is omitted (no midday meal during the fast). For patients on biphasic insulin: the pre-dawn dose may need reduction (risk of daytime hypoglycaemia during the long fast), and the evening dose is maintained or adjusted based on post-Iftar glucose levels. Blood glucose monitoring during Ramadan is essential — patients should test at least 2-3 times daily (pre-Suhoor, mid-afternoon, and pre-Iftar). Breaking the fast is required if glucose falls below 3.9 mmol/L — Islam explicitly permits breaking the fast for medical reasons.
Medications that break the fast: Oral medications and injections are considered to break the fast in Islamic jurisprudence (there is scholarly variation on injections — patients should consult their imam or Islamic scholar). Inhalers: the majority scholarly view is that metered-dose inhalers do not break the fast (as the medication enters the lungs, not the stomach), but patients may hold different personal or scholarly views. Eye drops, ear drops, and topical medications: generally considered not to break the fast. Suppositories and pessaries: scholarly opinion varies.
Having the Conversation
Before Ramadan: Proactive outreach is better than reactive management. Identify patients with diabetes, CKD, and other high-risk conditions 4-6 weeks before Ramadan. Offer a Ramadan consultation to discuss: whether fasting is medically advisable, what medication adjustments are needed, what symptoms should prompt breaking the fast, and blood glucose monitoring plans for diabetic patients.
During Ramadan: Respect the patient's autonomy. If a patient with a high-risk condition chooses to fast despite medical advice, your role is to minimise the risk — adjust medications, provide monitoring guidance, and ensure they know when to break the fast for medical safety. Avoid being dismissive of the religious importance of Ramadan — for observant Muslims, fasting is one of the five pillars of Islam. The conversation should be "how can we make this safe" rather than "you should not do this."
Cultural competence points: Do not assume all Muslim patients fast (some may not for personal, medical, or religious reasons). Do not assume patients who fast are being medically irresponsible. Do ask: "Are you planning to fast during Ramadan? Would you like to discuss your medications?" This normalises the conversation and positions you as a partner, not a gatekeeper.
Clinical Scenarios That Arise Every Ramadan
Dehydration. Particularly in elderly patients and those with CKD. Advise adequate hydration during non-fasting hours (2-3 litres between Iftar and Suhoor). Monitor renal function in patients with CKD who fast.
Hypoglycaemia in diabetic patients. The single highest-risk clinical scenario. The long fasting period (up to 19 hours in UK summer) with no food or drink creates sustained hypoglycaemia risk, especially in patients on insulin or sulfonylureas. Pre-Ramadan medication adjustment, regular glucose monitoring, and clear "break the fast" thresholds (glucose <3.9 mmol/L) are essential.
Medication non-adherence. Some patients stop medications entirely during Ramadan rather than adjusting timing — because they are unsure whether the medication breaks the fast, or because the timing adjustment was not discussed. A pre-Ramadan consultation prevents this.
Headache and fatigue. Common in the first few days of fasting — caffeine withdrawal (patients who normally drink 3-4 cups of coffee per day stopping abruptly) and dehydration. Advise gradual caffeine reduction in the weeks before Ramadan and adequate hydration during non-fasting hours.
Ask iatroX can support Ramadan-related clinical queries — "What is the recommended insulin adjustment for Ramadan fasting in type 2 diabetes?" / "Is amlodipine safe to take at Suhoor?" — with NICE/BNF-grounded answers. iatroX Calculators provides HbA1c interpretation, insulin dose calculators, and CKD-EPI for renal monitoring during Ramadan.