If a patient with type 2 diabetes mellitus does decide to fast:

• they should try and and eat a meal containing long-acting carbohydrates prior to sunrise (Suhoor)
• patients should be given a blood glucose monitor to allow them to check their glucose levels, particularly if they feel unwell
• for patients taking metformin the expert consensus is that the dose should be split one-third before sunrise (Suhoor) and two-thirds after sunset (Iftar)
• expert consensus also recommends switching once-daily sulfonylureas to after sunset. For patients taking twice-daily preparations such as gliclazide it is recommended that a larger proportion of the dose is taken after after sunset
• no adjustment is needed for patients taking pioglitazone