Effects of fasting on solid organ transplant recipients during Ramadan - a practical guide for healthcare professionals.

Fasting in the month of Ramadan is an obligatory act for healthy adult Muslims. It requires abstinence from food and drink from dawn to sunset. Although there are exemptions from fasting, many patients are keen to fulfil what they see as a religious obligation, even if this may be against medical advice in some cases. Solid organ transplant (SOT) recipients often ask healthcare professionals for advice on fasting. Studies on the effect of fasting in transplant patients have all been done in the Middle East and North Africa where the average fasting duration is between 12 and 14 hours. In comparison, in temperate regions in the summer, fasting duration can be as long as 20 hours. Fasting when patients have to take immunosuppression 12 hours apart with little time variation poses unique challenges. In this review, current literature is reviewed, and a decision-making tool has been developed to assist clinicians in discussing the risks of fasting in transplant recipients, with consideration also given to circumstances such as the COVID-19 pandemic.Our review highlights that SOT recipients wishing to fast should undergo a thorough risk assessment, ideally 3 months before Ramadan. They may require medication changes and a plan for regular monitoring of graft function and electrolytes in order to fast safely. Recommendations have been based on risk tiers (very high risk, high risk and low/moderate risk) established by the International Diabetes Federation and the Diabetes and Ramadan International Alliance. Patients in the 'very high risk' and 'high risk' categories should be encouraged to explore alternative options to fasting such as winter fasting or Fidyah. Those in the 'low/moderate' category may be able to cautiously fast with guidance from their clinician. Prior to the commencement of Ramadan, all patients must receive up-to-date education on sick-day rules, instructions on when to terminate their fast or abstain from fasting. © Royal College of Physicians 2021. All rights reserved.