Ramadan and Diabetes: Medical Challenges, Concerns and Considerations

Individualization is key to diabetes management during Ramadan, a month of fasting, for patients who follow Islam.

Though Ramadan represents a period of reflection and religious devotion for those who follow Islam, it can also present a significant medical challenge for endocrinologists and their Muslim patients with diabetes.

Ramadan is a lunar-based month that can last from 29 to 30 days during which many Muslims fast. Because the lunar calendar is about 11 days shorter than the solar calendar, Islamic holidays move each year. In 2015, Ramadan is expected to begin at sundown on June 18 in the United States, with dates varying throughout the world. Depending on the geographical location and season, the duration of the daily fast may range from a few hours to more than 20 hours.

However, although the timing may range from city to city and country to country, the challenges that patients with diabetes face remain the same, according to experts.

Dietary Concerns

One major problem for patients with diabetes during Ramadan is diet.

Ramadan involves fasting during the day, but there are no restrictions on food or fluid intake between sunset and dawn. Therefore, during this time, many Muslims consume two meals per day, often having one after sunset and another before sunrise.

Unfortunately, complications can occur in patients with diabetes during this time due to overeating and insufficient sleep that arise from these changes in eating patterns.

Although no evidence-based guidelines exist, clinicians recommend that an individual’s diet should not differ significantly during Ramadan for patients with diabetes. Meals need to be healthy and balanced, with a goal of maintaining the same BMI, according to Kim A. Carmichael, MD, who is an associate professor of medicine in the division of endocrinology, metabolism and lipid research at the Washington University School of Medicine in St. Louis. 

Nevertheless, this is not always the case. One significant concern, for instance, is the common practice of ingesting large amounts of foods rich in carbohydrates and fats at the sunset meal. Clearly, this is something that should be avoided and discussed with patients with diabetes. Clinicians instead suggest that patients eat foods containing “complex” carbohydrates at the predawn meal because these foods are more likely to delay ingestion and absorption.

“Important factors to improve safety include a sensible diet, minimizing the use of simple carbohydrates and fats during the evening and early morning meals, maintaining good sleep hygiene, avoiding excessive exercise, maintaining adequate fluid intake and checking blood glucose levels frequently,” Carmichael told Endocrinology Advisor

Importance of Monitoring Medications

Another problem that clinicians and patients need to keep tabs on is careful monitoring of medications during Ramadan.

“In general, insulin and sulfonylureas increase the risk of hypoglycemia and their effects may be potentiated by other agents, dehydration or altered diet. Sulfonylureas in general should be avoided since they are hard to adjust and regulate,” Carmichael said.

However, he noted that sulfonylureas are relatively inexpensive and commonly prescribed. So, Carmichael said clinicians and patients should exercise extreme caution if their use is deemed necessary during Ramadan.

Glinides may be substituted since they are short-acting and may be timed with meals, he added.

Additionally, insulin therapy is best given with a flexible regimen, according to Carmichael. Consequently, specific adjustments in the timing and amounts given must be based on the new mealtime and activity schedule. All patients on insulin should discuss an individual plan with their health care team 4 to 8 weeks before Ramadan. 

“Metformin therapy is considered to be safe during Ramadan, as long as persons maintain good fluid intake. Other classes considered to be safe include DPP-4 inhibitors, GLP-1 agonists, an amylin analog, thiazolidinediones and alpha-glucosidase inhibitors. There are no data regarding the newer class of SGLT2 inhibitors, but since these increase the risk of dehydration and hypotension, they would need to be given with caution,” explained Carmichael.

Michael Fowler, MD, who is an associate professor of medicine and director of Vanderbilt Diabetes Outreach in the division of diabetes, endocrinology and metabolism at Vanderbilt University Medical Center in Nashville, Tennessee, also underscored the importance of assessing medications and treatment regimens during Ramadan.

Sulfonylureas and metaglinides trigger endogenous insulin release, he said, and the absence of these agents in individuals who normally take them predispose patients to fasting hypoglycemia. This is especially true when activity levels are high, Fowler said.

Also, patients using mealtime insulin should continue to use insulin when they eat in order to control postprandial hyperglycemia, he noted.

“Patients may need to use regular or rapid-acting insulin in ‘correction’ doses in the event of hyperglycemia, but this should be done with caution,” Fowler told Endocrinology Advisor.

“Basal insulin is a different matter. This is provided by agents such as insulin glargine and detemir in the United States. In other countries, insulin degludec and ultralente insulin may be available. Basal insulin acts to keep blood sugar stable during the fasting state; therefore, when dosed carefully, blood sugar should remain stable when a person is not eating,” he said.

“The catch is that if activity level increases, if someone’s dose is too high already or if a patient loses weight and becomes more insulin-sensitive during the month of Ramadan, they may still experience hypoglycemia while fasting.”

Fowler said he keeps his patients with type 2 diabetes on basal insulin, but reduces the dosage by 10% to 20% during the month of Ramadan. He does this because many patients tend to lose weight during this time.

However, all agents can cause hypoglycemia, Fowler cautioned, but some agents are much less likely to do so than others.

“Ones less likely to do so during the fasting state include metformin, DPP-4 inhibitors such as sitagliptin, SGLT2 inhibitors such as canagliflozin, GLP-1 agonists such as exenatide, thiazolidinediones such as pioglitazone and alpha-glucosidase inhibitors such as acarbose. Using these agents, the risk of hypoglycemia is low, but not zero,” he said.

“If the patient is not drinking liquids during Ramadan — some of my patients drink water during their Ramadan fast and some do not — they should avoid therapies which could promote dehydration, such as alpha-glucosidase inhibitors and SGLT2 inhibitors, since both of these agents will promote water loss. If a patient is at risk for pre-renal azotemia from dehydration. they should also stop metformin.” 

Patients with type 1 diabetes should never stop their basal insulin, Fowler said. A small reduction in insulin dosage may be warranted, especially if the patient loses some weight, but he said withholding basal insulin would inevitably result in diabetic ketoacidosis. Fowler recommends patients continue to use rapid-acting insulin when they eat, usually based on their insulin-to-carbohydrate ratio.

It is generally recommended that all patients have the means to monitor their blood glucose levels several times a day, and this is particularly important in patients who take insulin. Carmichael said the fast should be broken immediately in the event of extreme hypoglycemia or hyperglycemia. 

“Persons prone to frequent hypoglycemia should carry a medical alert identification and have a glucagon injection device for emergency use. Persons should avoid fasting on sick days. Fasting is also not medically advised during pregnancy so expectant mothers observing Ramadan will need intensive monitoring by a high-risk specialty group,” said Carmichael.

A Growing Issue

There are an estimated 1.57 billion Muslims in the world, and it is also the world’s second largest religious group, according to the Pew Research Center.1 Additionally, the ranks are growing rapidly, partially due to differences in fertility rates and the size of youth populations among the world’s largest religions.

By 2050, the Pew Research Center estimates Islam will replace Judaism as the largest non-Christian religion in the United States.

With these numbers increasing, more endocrinologists are now managing Muslim patients with diabetes who are passionate about their religious tenets. The fact that more and more Muslims are developing diabetes after adopting more Western-style eating habits is further compounding the issue.

Fasting during Ramadan, however, has been uniformly discouraged by the medical profession for patients with diabetes.

“The Holy Koran specifically exempts the sick from the duty of fasting, especially if fasting leads to comorbidities for the individual. Patients with diabetes mellitus fall under this category because their chronic metabolic disorder may place them at high risk for various complications, if the pattern and amount of their meal and fluid intake is markedly altered,” Farhad Zangenah, assistant clinical professor of medicine at George Washington University School of Medicine in Sterling, Virginia, told Endocrinology Advisor.

“Nevertheless, many patients with diabetes insist on fasting during Ramadan,” he said.

Many Muslims with diabetes insist on fasting as an expression of their faith or for other reasons, but some patients do end up in the hospital for a host of complications. As the number of Muslims in the U.S. continues to grow, it is expected that more hospitals will need to be prepared to treat an increasing number of patients with diabetes in the emergency room during the month of Ramadan. 

“Hospitalizations have increased for type 1 and type 2 diabetes during this month for hypoglycemia and hyperglycemia. The risks include diabetic ketoacidosis, dehydration, syncope, falls, orthostatic and hypotension,” said Zangenah.

“The most important potential complications of diabetes during Ramadan are poor glucose control and dehydration. Although there are few studies on these, the incidence of hypoglycemia may increase up to 4.7-fold in type 1 diabetes and 7.5-fold in type 2 diabetes.”

Additionally, in patients with type 1 diabetes, there may be an increase in the risk for dangerous hyperglycemia, Carmichael said, but most experts agree that this risk may be reduced by having better glucose control before Ramadan.

Zangenah also emphasized the need for evidence-based guidelines for managing patients with diabetes who want to fast during Ramadan, and there has been a call for this issue to be addressed sooner rather than later.2

Until then, even though Ramadan can be a challenge for patients with diabetes, clinicians contend that it can be an opportunity to improve diabetes management education overall. Studies suggest that the best possible approach is advanced education for each patient and making sure that all treatment plans are highly tailored to that specific patient.

“Medication management must be individualized, particularly as many persons with diabetes take multiple types of agents,” said Carmichael.


  1. The Future of World Religions: Population Growth Projections, 2010-2050. Pew Research Center website. http://www.pewforum.org/2015/04/02/religious-projections-2010-2050/. April 2, 2015. Accessed June 2015.
  2. Yaqub F. Lancet Diabetes Endocrinol. 2014;2(6):454.