A constant cough can be disruptive for any person but when it comes to diabetics, it does complicate matters. For starters, a person with diabetes cannot just reach out for any over the counter (OTC) cough syrup because it is likely to be rich in sugar. Secondly, the cough is often the result of a cold and this puts additional stress on the body, causing blood sugar levels to rise. Therefore, dealing with cough in diabetics requires much greater care and attention.

Cold, cough and blood sugar – what’s the link?

If the cough and cold is the result of an infection, the body seeks to combat it by releasing greater quantities of hormones to fight the infection. While this is good for people without diabetes, it can create complications for diabetic persons because, as the American Diabetes Association explains, these hormones interfere with the action of insulin in the body. Whether it is the natural insulin produced by the pancreas or the insulin a person receives as part of anti-diabetic therapy, this hormonal interference is likely to result in higher blood sugar levels.

If a diabetic person has cough and cold that lasts for more than a week, the chronically elevated blood glucose levels can lead to other complications such as ketoacidosis where too much acid builds up in the blood.[4](Reference) This makes it even more crucial for diabetics to deal with their cough and cold symptoms at once, without waiting for it to go away on its own.

Composition of cough products

Like all pharmaceutical formulations, OTC cough syrups contain certain active ingredients (the actual drugs responsible for the therapeutic effect) and some inactive materials (solvents, coloring agents, flavoring agents and preservatives) that help to give a palatable and aesthetic product. Both active as well as inactive ingredients in conventional cough syrups can potentially affect blood glucose levels or other critical functions in a diabetic patient.

Sugar and alcohol in cough syrups are the main culprits likely to cause fluctuations in blood sugar in diabetics. Sugar is the main inactive ingredient in most cough syrups and when absorbed into the blood, will directly cause a major spike in blood glucose levels.

Writing in the “Living with Diabetes” blog of the Mayo Clinic, Nancy Klobassa Davidson, R.N. and Peggy Moreland, R.N. explain that consumption of alcohol can lead to diabetic complications.[2,3] Considering that quite a few cough syrups also contain alcohol, it is important to remember that this can also affect the body’s metabolic pathways to increase blood glucose levels.

When it comes to active ingredients in cough syrups, the common drugs used are dextromethorphan and guaifenesin; both these are considered safe for diabetics at prescribed doses. However, most cough syrups may also include other drugs such as paracetamol and ibuprofen to help reduce pain – both these drugs can have toxic effects on diabetics who have kidney complications. Besides, ibuprofen also has the tendency to enhance the blood-glucose lowering effect of anti-diabetic medication.[5](Reference) Decongestants and antihistamines that are present in cough syrups may also
interfere with the way the body metabolizes sugar, insulin and anti-diabetic medicines in diabetics.

Conventional cough sugar based lozenges are equally taboo for diabetics; these are nothing but a hardened version of a sugar concentrate that also contains cough medication. Whether it is a medicated lozenge or a herbal lozenge that contains ingredients such as tulsi, menthol or ginger, the fact remains that it is rich in sugar and is best avoided. It is also advisable for diabetics with cough to think twice before taking herbal lozenges that contain honey because this can also have an effect on blood glucose levels.

What is the solution?

In other words, diabetics cannot just reach out for any OTC product when they suffer from cough and cold; it is vital they consider the effect of such medication on their disorder. Most liquid medicines for cough and cold contain added sugar but there are safer products such as the new product range from Benadryl – this has a formula that is designed specifically for treating cough in diabetics and therefore, is a better option than conventional cough syrups.

Besides, it is also advisable that diabetics check blood sugar levels more regularly when they have a cough and cold. Information about the changes in sugar levels can help your doctor determine the right medication to help you recover faster.

Drinking a herbal tea or kashaaya can help soothe an irritated throat but diabetics ought to pay attention to the ingredients that feature in such teas – substances such as cinnamon may tend to reduce blood sugar levels and others such as honey can cause levels to rise; so it is important to exercise due caution and speak to a doctor before taking any such home remedy.

Considering the complications of treating cough and cold in diabetics, it is best to take measures to prevent contracting them in the first place. For this, it is vital to practice good hygiene to avoid catching a cold from someone in the family; it is equally important to stay alert and tackle a cough at the earliest.