An important component of pre-Ramadan education is medication adjustments. In general, medications that are typically taken once a day in the morning, such as extended-release metformin, once-daily sulfonylureas, SGLT-2 inhibitors, most DPP-4 inhibitors, and most blood pressure-lowering medications, can be taken at iftar. Medications that are taken twice-daily, such as regular-release metformin, twice-daily sulfonylureas, vildagliptin, and some blood pressure-lowering medications, can be taken at sahur and at iftar. Less commonly, metformin is taken three times daily, or with higher morning dose followed by a lower dinner dose. These doses can be modified by switching the higher dose from morning to iftar, and vice-versa. The mid-day dose of metformin can be combined and taken together with iftar dose.
Metformin dose adjustment during Ramadan. Image from IDF-DAR (click on image to zoom).
Insulin dose adjustments are also necessary during Ramadan. Given that the risk of hypoglycaemia is highest before iftar, the morning doses of insulin should generally be reduced by 25% to 50%, depending on the individual's glucose control. The dose of basal insulin taken the day prior to fasting may also need to be reduced by 15% to 30% to reduce the risk of hypoglycaemia.
Some people may require a higher dose of mealtime insulin at iftar if they consume more carbohydrate than usual during iftar.
Dose adjustments for basal insulin and meal insulin (short-acting insulin) during Ramadan. Image from IDF-DAR (click on image to zoom).
Patients with diabetes who are treated with premixed insulin should also adjust their insulin doses. If the premixed insulin dose is taken at equal doses twice daily, the sahur dose should be reduced by 20% to 50%. If the usual dose of premixed insulin at breakfast is higher than dinner, the doses should be switched with the higher dose taken at iftar and lower dose taken at sahur. This sahur dose can further be reduced depending on the risk of hypo- or hyperglycaemia.
Premixed insulin dose adjustments during Ramadan. Image from IDF-DAR (click on image to zoom).
Regardless of insulin dose adjustments, insulin dose titration is still required in most cases. Basal insulin and the dose of premixed insulin during sahur can be titrated according to blood glucose before iftar, whereas the dose of premixed insulin during iftar can be titrated according to blood glucose before sahur. Short-acting or rapid-acting insulin doses taken at sahur or iftar can be titrated according to post-meal blood glucose, typically after 2 hours.
Insulin titration during Ramadan. Image from IDF-DAR (click on image to zoom).
Patients who are using insulin pumps are advised to reduce their basal rate by 20% to 35% in the last 4-5 hours before iftar, and increase their basal insulin rate by 10% to 30% from iftar to midnight. Having 2 separate basal profiles for fasting and non-fasting days may be useful for easier profile switching between different days. Mealtime insulin can be administered based on the regular insulin-carb ratio (ICR) as long as it follows the changes in carbohydrate amounts taken during sahur and iftar. People who use continuous glucose monitoring and sensor-augmented insulin pumps have lower risk of hypoglycaemia, and these additional monitoring devices may be considered during Ramadan. At the moment, there is no data with regards to those using hybrid closed-loop system and Ramadan fasting. They are likely to experience less hypo- and hyperglycaemia, but whether they should follow similar dose adjustments for other insulin pump users remains to be seen.
Dose adjustments for insulin pumps during Ramadan. Image from IDF-DAR (click on image to zoom).