The Muslim holy month of Ramadan begins May 27. And for those who observe its rules on fasting, there are implications about taking medication. 

During Ramadan, Muslims don't eat, drink or swallow any medication from dawn to dusk.

However, there's a knowledge gap among health care professionals unfamiliar with the custom. And they may not know how to manage medication for patients who choose to fast during Ramadan.

"There are lots of issues that health care professionals don't know in terms of what to do when changing medications and – most importantly – people who can not go safely without their medication should be exempted and should not fast," Wasem Alsabbagh, a pharmacist and assistant professor at the University of Waterloo School of Pharmacy told CBC's The Morning Edition host Craig Norris on Tuesday.

What should providers know?

Alsabbagh said one of the most important things healthcare professionals should do is have an open conversation with their patients in order to go over some of the risk factors.

If a patient chooses to fast, there are ways to change the regular time they should take their medication. For example, if a person takes their medication multiple times a day, healthcare professionals can substitute long-acting forms of medication that only need to be taken once or twice daily.

"Pharmacists have what we call 'expanded scope of practice' so they can adapt prescriptions and change doses," he said.

Health care professionals should also know and have a conversation with their patients about food and fluid intake, such as drinking more water in the evening and making sure the pre-dawn meal, Suhoor, is balanced and nutritious.

Many exempted choose to fast

"If you read the rules around fasting in Islamic literature, if you are sick or chronically ill you are exempted," said Alsabbagh.

However, those who may be exempted often choose to fast because it is a very important religious practice for many Muslims.

"A survey was done and it showed that 80 per cent of patients who have Type 2 diabetes still choose to fast," he said. "More than 40 per cent of people with Type 1 diabetes, those who use insulin, still choose to fast."

Longer days

Because of the lengthening daylight hours at this time of year, fasting can be as long as 15 hours.

Alsabbagh said people who cannot go safely from dawn to dusk without their medication can do other things to observe the holy month of Ramadan.

He said patients can make up their fasting days at other times of the year when the days are shorter. And if a patient can't fast, they can also honour Ramadan through charitable activities.