Choosing a Antihistamine for Diabetics

Page content

Many diabetic people who experience symptoms of flu, colds, cough and allergies are often not sure if they are suffering from infection or allergies. The symptoms may be similar and so people often buy over-the-counter drugs (OTC) that contain combinations of ingredients which target these symptoms all at once. These symptoms may include headache, fever, runny nose and weakness, for which OTC drugs combining pain relievers, antihistamines, nasal decongestants, cough suppressants and other ingredients are sold.

How Do OTC Antihistamines Work?

Antihistamines block the action of histamines which are produced by normal cells in reaction to allergens, thus preventing symptoms like runny nose, excessive tearing, itchiness and other allergic reactions. OTC antihistamines are usually combined with other drugs such as nasal decongestants, cough suppressants, expectorants, pain relievers, etc to relieve cough, colds and other flu symptoms.

First generation or older preparations of antihistamines often cause drowsiness. Examples of these are diphenhydramine (Benadryl) and chlorpheniramine (Chlortrimeton). These are usually taken when one is expected to rest in bed and contraindicated for persons who are driving vehicles or heavy equipment.

Second generation antihistamines are the newer class of drugs which are non-sedating and are taken by people who work or go to school. They include certirizine (Zyrtec) and loratadine (Claritin).

Choosing the Right Antihistamine

It is important to choose the right type of OTC antihistamines for people with diabetes, heart disease, and other chronic conditions. Diabetics usually suffer from other medical conditions brought about by the disease, such as hypertension, kidney and neurologic complications. For these reasons it is best to avoid certain drugs with certain ingredients or combinations of drugs.

Criteria for choosing the right antihistamine for diabetics include:

  • Does not contain sugar – some cough and cold preparations (usually in syrup form) contain sugar for flavoring, and may cause an increase in blood sugar level.
  • Does not contain alcohol – some syrups are combined with alcohol, which may cause a decrease in blood glucose level.
  • Does not contain stimulants like pseudoephedrine, phenylephrine, and phenylpropalamine – often found in nasal decongestants, and can cause increases in blood pressure and blood glucose level. These can also cause jitteriness, nervousness and difficulty in urination. Diabetics with hypertension and kidney problems should definitely avoid these drugs.
  • Does not contain some nonsteroidal anti-inflammatory drugs like ibuprofen and naproxen – can also increase blood pressure and kidney problems.
  • Sedating antihistamines must be taken at night or when one is taking a rest in bed. It should not be used during the day when excessive drowsiness may endanger one’s safety. An example of pure antihistamine that can cause sleepiness is Benadryl.
  • Non-sedating antihistamines may be taken by people who work or go to school. Loratidine is an example.

As a rule, antihistamines alone relieve runny nose, excessive tearing, sneezing, postnasal discharge, conjunctivitis and itchiness. When a person with diabetes is experiencing other symptoms like fever, cough and nasal congestion, specific but safe medications must be opted for. For example, acetaminophen is recommended for fever and body aches, instead of ibuprofen. For cough, one may take dextromethorphan which is an antitussive (controls cough). For ease in expectoration or excreting mucus one may have guiafenesin. These medications may be bought separately, and are preferred than taking combinations in one drug.

Many factors may cause increases or decreases in blood sugar levels in diabetic patients, among which are certain medications. Avoiding complications from OTC drug side effects is important in managing diabetes and its complications. Choosing the right medication for specific symptoms and conditions may be accomplished with proper information and help from health care workers including doctors, nurses and pharmacists.

References, “Cold Medicines That Are Safe for Diabetes”,

American Academy of Otolaryngology — Head and Neck Surgery, “Antihistamines, Decongestants, and Cold Remedies”,