Sir,Ramadan is the ninth month of the Islamic lunar calendar. During this month, millions of mature and healthy Muslims fast from dawn to dusk. The fast comprises abstinence from food, sexual intercourse, and immoral activities. This period lasts for around 12 h. Muslims generally consume a large meal before and another one after the fast. Certain groups of people such as pregnant or menstruating women, travelers, and patients are exempted. However, many of them choose to fast despite their exemption.According to a recent study, there are 1.57 billion Muslims worldwide, which makes around 23% of the world population.[12] Therefore, it can be predicted that patients with common chronic diseases may be seen during a fast. An idea of the sheer size of this problem can be gained by looking at the statistics of fasting diabetics. According to an estimate, 40–50 million diabetics fast during Ramadan each year worldwide.[3] A drastic change such as a fast may lead to adverse events in these patients. However, until very recently, no guidelines were available which would dictate the action of clinicians concerning the fasting patients, diabetics, or otherwise, in Ramadan.Although some guidelines have been formulated,[1] most diseases that may be present in fasting patients remain ignored. Due to the major change in dietary habits and the inability of fasting patients to take their prescribed medicines on time during the fast, there is a higher risk of certain diseases in Ramadan, such as diabetes, ulcers, and asthma.[4] Especially likely to exacerbate in such conditions are those diseases which require a strict control over drug intake or require emergency treatment. This makes fasting individuals a special population with different needs than the nonfasting population. Without the presence of evidence-based guidelines, the treatment of such cases is on the subjective judgment of the clinician, which may or may not lead to optimal clinical outcomes.There is an urgent need to monitor the medical effects of Ramadan fasting and to conduct prospective or retrospective clinical studies in order to identify the best management options in these cases. This would subsequently lead to the development of evidence-based guidelines for these patients. The sheer size of this medical problem warrants that more robust medical attention is provided to this problem. It is important to mention here that forbidding fasting in patients is out of our domain since this is a religious instead of a medical issue. The decision to fast should entirely depend on patient's own will. This is a complex issue for clinicians because it mixes religious and medical considerations. However, the focus should be on the next best thing: making the fast as safe and healthy for patients as possible.