Pharmacy U

For patients with diabetes, colds and flu present challenges


Cold and flu season presents unique challenges to your patients living with diabetes. You’ll need to make specific recommendations to help them prevent and manage their symptoms, and at the same time, you’ll need to make them aware of diabetes management issues for sick days.

By Shelley Diamond, BScPhm

Illustration by Martin Bregman

Managing colds

Try non-pharmacologic management first – fluids and lots of rest.

For sore throat relief, suggest they try salt-water rinses or sugar-free throat lozenges.

For congestion, suggest saline nose rinses.

Below are a few things to remember if using over-the-counter products to relieve symptoms specific to people with diabetes:

  • Make sure you select sugar-free products.
  • Choose a solid dosage form over a liquid to reduce the amount of carbohydrate (glucose).
  • Remember that oral decongestants may cause a rise in blood pressure and blood glucose.

Your patients may ask you about herbal, homeopathic, and other complementary and alternative treatments that are on the market for managing colds. For people without diabetes, there is some evidence that using zinc or vitamin C may reduce the severity and duration of a cold.

Managing flu

Specific concerns regarding flu for people with diabetes:

  • People with diabetes are at higher risk of developing complications from influenza. The most common complication is pneumonia.
  • Consider antiviral medications if they can be administered within 48 hours of the onset of symptoms.

Your patients may ask you about herbal, homeopathic, and other complementary and alternative treatments that are on the market for managing influenza. Unfortunately, there have been few well-designed studies to evaluate their efficacy and safety.

Managing diabetes with a cold or flu

When people with diabetes are ill, blood glucose levels can fluctuate and be unpredictable.

  • Have your patients drink extra sugar-free fluids or water; try to avoid caffeine-containing drinks, which increase fluid loss. If patients are not able to eat according to their usual meal plan, they can use glucose-containing fluids in place of solid food. In this situation, the goal would be to drink fluids with 15g carbohydrate every 1-2 hours.
  • If your patients are on insulin, stress that they need to continue taking it while they are sick but do require increased self-testing of bloodglucose (usually every two-four hours) for appropriate adjustment of dosing.Some medications should be held if patients can’t maintain adequate fluid intake or if their renal function declines acutely.These include the medications that increase risk for a decline in kidney function:
    • Angiotensin-converting enzyme inhibitors
    • Angiotensin receptor blockers
    • Direct renin inhibitors
    • Non-steroidal anti-inflammatory drugs
    • Diuretics

    Have reduced clearance and increase risk for adverse effects:

    • Metformin
    • Sulfonylureas (gliclazide, glimepiride, glyburide)


Suggest they see their doctor or go to an emergency room if they vomit and/or have had diarrhea two times or more in four hours.

Tips for preventing cold and flu

  • Handwashing, handwashing, handwashing! In most situations, washing hands with soap and water eliminates most microbes and is especially recommended if there is any visible dirt.
  • To date, studies have shown there is no added health benefit for people using soaps containing antibacterial ingredients compared with using plain soap.
  • If soap and water are not available, use an alcohol-based hand sanitizer that contains at least 60% alcohol.
  • People with diabetes should receive an annual influenza immunization to reduce the risk of complications associated with influenza (Canadian Diabetes Association 2013 Clinical Practice Guidelines).

Pharmacist Shelley Diamond is president, Pedipharm Consultants, and co-founder/president, Diabetes Care Community Inc., an extensive online resource for Canadians living with diabetes, their families and healthcare professionals.