Side effects of decongestants in cold and flu season

There are over 200 subtypes of the common cold (British Medical Journal (BMJ), 2022) and most people experience one cold in a year, which is usually self-limiting and lasts less than a week (BMJ, 2022). This involves inflammation of the upper respiratory tract mucosa, which may affect the nose, throat, sinuses and larynx, producing sore throat, sneezing, blocked or runny nose, headaches, cough, malaise and low-level fever. However, frailer patients are at higher risk of a more severe degree of illness from a cold.

Flu is a more severe illness that has similar symptoms to the common cold, and can have a detrimental impact on the vulnerable. Influenza is categorised as type A, B or C. Type A is more virulent and frequent, B involves milder disease but can still cause outbreaks, and C causes mild or no symptoms which are similar to the common cold (British National Formulary (BNF), 2022a). With flu, you may see more extreme fatigue, chills, fever and myalgia, and there may be a dry cough and nasal congestion. Complications of flu include bronchitis, secondary bacterial pneumonia, and may at times be cardiac or neurological in presentation (BNF, 2022a).