Treating the Common Cold and Type 2 Diabetes

by diabetes care guide

It is that time of year again and as a Pharmacist/Certified Diabetes Educator one of the most common questions over the fall, the holiday’s and winter months is “What do you have to treat my cold?” or simply “Can you make me feel better?” Well there is no cure and we cannot wave our “therapeutic” wand and make symptoms disappear but there are a variety of products to help with the symptoms of cough and cold. If the patient is relatively healthy it may be a bit of a hit or miss scenario but usually the product will ease the symptoms until the cold runs its course over 7 to 10 days.

The picture becomes less clear when the patient is taking other medications, has medical conditions such as kidney disease, blood pressure, or they have diabetes.

Assisting our patient choose an appropriate product that will not worsen their existing medical conditions, and lessen the symptoms that make them feel miserable is key.

Diabetes is a condition that requires some adjusting to choose the right product. It is not always a “Sugar free”, “Natural”, or alternative product that is best, as active ingredients may have issues. These include raising blood sugars, raising blood pressure or stressing the kidneys (common issues with diabetes). Usually after a brief discussion to educate the patient, a product can be chosen to help both their symptoms and minimally impact their diabetes and blood sugars.

The discussion that follows is a practical approach on how to decide what a person with diabetes can use so that they understand why we avoid certain classes of products due to a their existing medical conditions.

Blood Sugars Can Rise when Ill

It is important to realize that when a person with diabetes is “fighting” a cold it produces stresses on the body as a whole and may be associated with fluctuations in blood sugar. This may be related to the stress of being sick or to changes in what they eat during illness. A severe bout of the common cold (a viral illness) can elevate blood sugars on its own, without any effects from nonprescription or other medications. Simply put, when patients are sick they should test their blood more often to keep an eye on what’s happening. This is important as most assume that because they may be eating less their blood sugars would be lower. In fact, blood sugars tend to rise as a defense against the virus and to help the body fight the effects of feeling ill.

Checking Medications & Interactions

Patients with diabetes should be reminded to always contact a health care provider especially their pharmacist prior to taking new nonprescription medications. Many over the counter cold medications contain multiple ingredients some of which are compatible with diabetes and its complications while others may have unwanted effects. Natural/Herbal products being taken should be reviewed as well as any prescription medications.

Classes of nonprescription medications commonly used to relieve symptoms of the common cold include decongestants, antihistamines, analgesics/antipyretics, antitussives, expectorants and traditional/simple remedies.

Decongestants relieve the nasal stuffiness and congestion characteristic of the common cold. In oral form, the most common decongestants are pseudoephedrine (Sudafed®) and phenylephrine (Dimetapp®). Oral decongestants as a category have the most potential for affecting blood sugar control as well as elevating blood pressure. They can increase blood sugar by preventing insulin secretion, by decreasing glucose uptake into peripheral tissues and by stimulating glycogen breakdown. Blood pressure can be elevated by its vasoconstricting effect on blood vessels. Diabetic patients should definitely check with their health care providers before using an oral decongestant. Sometimes choosing a lower dose or choosing the best time of day to use it can limit the unwanted side effect of the medication and provide the desired relief.

As an alternative, topical decongestants such as nasal sprays 0.1% xylometazoline HCL (Otrivin®) Phenylnephrine 0.5% and Pheniramine 0.2% (Dristan®) are thought to have a more localized effect with less effect overall. The most common issue with topical decongestants is the experience of “rebound congestion”. This occurs when the nasal spray is used more than recommended or longer than 2-3 days and results in symptoms that can considerably worsen or become chronic, resulting in a patient’s continuous use to open the nasal passages. Although less common than in the past it is still necessary to educate the patient so it does not become an issue.

Antihistamines, more commonly used to treat allergic rhinitis, may have some limited benefit against the common cold as they decrease runny nose and sneezing. Common nonprescription antihistamines include the traditional antihistamines that can cause drowsiness – diphenhydramine (Benadryl®) and chlorpheniramine (Chlor-Tripolon®). Non-traditional antihistamines that do not cause drowsiness include loratadine (Claritin® and store brands), cetirizine (Reactine® and store brands), desloratidine (Aerius® and store brands). This class of drugs has no effect on blood sugar. Again caution is needed as antihistamines are commonly found as part of combination products that may have additional active ingredients which may cause concern.

Analgesics are used for aches and pains associated with the common cold, and antipyretics address fever.

Aspirin, acetaminophen (Tylenol®), ibuprofen (Advil®), naproxen (Aleve®) are nonprescription members of this category. Although low dose aspirin (81 mg to 325mg per day) is recommended for diabetic patients, as secondary prevention in cardiovascular disease (under review as some studies are showing low or no benefit), very high dosages of aspirin and other salicylate drugs can cause hypoglycemia and should be avoided by diabetic patients. Aspirin should not be given in any dosage to children who have a viral infection, as it may precipitate a severe illness known as Reye’s syndrome. Acetaminophen is probably the safest analgesic/antipyretic for diabetic patients. Ibuprofen (Advil®, Motrin® and store brands) and naproxen (Aleve®) do not have significant effects on blood sugar, but should be used with caution by patients who have kidney disease.

Antitussive agents help suppress cough. The most common active ingredient in this class is dextromethorphan (DM). Diphenhydramine, an antihistamine, described above, can also have antitussive properties, though considered “second line” or less for cough. Codeine containing products are available behind the pharmacists counter without a prescription but are combined with other ingredients that may raise “red flags” with our patients with diabetes. None of these cough suppressant medications significantly affect blood sugar control. As mentioned above this class “Antitussives” can be found as single ingredients products (Delsym, DM – syrups, etc) they are more commonly found as part of a “Multi Symptom Product” which may pose concerns for patients with diabetes.

Expectorants are the final major category of agents used to treat symptoms of the common cold. These medications loosen respiratory tract secretions and make coughs more productive. The most common active ingredient in this category is guaifenesin – which has no effect on blood sugar control. These are found in single ingredient products like Robitussin® Plain, Benylin®-E®, store brand expectorant syrup). It is also commonly combined with other ingredients in multi symptom cold products, so there is a need to read that label.

Simple and Topical Approaches are often overlooked however they frequently provide the desired relief for patients.

Menthol lozenges such as Fisherman’s Friend® can soothe to an irritated throat and make the sinuses feel clearer and are available in both “Sucrose Free” as well as regular varieties.

Saline solutions can be used to dilute mucous and promote easier breathing and diluted mouthwash gargle to soothe a sore throat can lessen symptoms without risk of affecting the patient’s blood sugar.

Products to reduce the severity and length of colds such as ColdFx® can usually be safely used by patients with diabetes and may also provide a degree of relief.


An important note is that all over-the-counter (OTC) cough and cold products will have a ‘WARNINGS” label on the package. The warnings are generally very inclusive and this is where patients with diabetes should seek advice to ensure that the product is safe for their use.

Keep it Simple to Avoid Complications

Depending on the individual, patients with type 1 or type 2 diabetes, with a cold, will have elevated blood sugars to some extent.

Consider the actual sugar content of the product chosen and is it of concern. Most products are manufactured to have minimal caloric value per dose. Most cough syrups only have 5 calories or less per dose. While some of the nighttime products NeoCitran® or Nyquil® can be higher, it is up to us to help the patient decide if it can be used safely.

When the patient has many “red flags”, we need to choose a therapy that can provide comfort without worsening existing medical conditions.

This is an area where the “traditional/simple” therapies are often the most appropriate. Saline sprays, Fisherman’s Friend® Sucrose Free menthol lozenges, camphor base rubs (Vicks® Vapor Rub) camphor inhalers (Vicks®), salt water or diluted mouthwash gargles can provide these patients with relief for their colds.

Remember to keep it simple, keep it safe and by asking some questions we will usually be able to offer a few suggestions and hopefully get them back on their feet sooner rather than later.

As always seek qualified medical advice regarding your diabetes care screening and treatment.

“Treating the Common Cold and Type 2 Diabetes” By Robert S. Roscoe B. Sc. Pharmacy, CDE (Certified Diabetes Educator), CPT (Certified Insulin Pump Trainer).

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