Allegra-M for a dry cough

Products sold under this name commonly combine the antihistamine fexofenadine with montelukast, although ingredients can vary by market and product. The combination targets allergic inflammation and may reduce coughing driven by nasal allergy or asthma; it does not address every cause of cough.

A dry cough can accompany allergic rhinitis, asthma, a common cold or irritation after a respiratory infection. Acid reflux, smoke, perfumes and some medicines can also trigger it. Allergic rhinitis often presents with sneezing, nasal itching, clear discharge and throat clearing; asthma can present with cough, wheeze, chest tightness or breathlessness.

Montelukast can cause mood, sleep or behaviour changes in some people. New nightmares, agitation, low mood, unusual thoughts or other concerning changes warrant stopping the medicine and contacting the prescriber promptly.

Read the label to confirm both active ingredients and use the product only for the person it was prescribed or recommended for. Discuss pregnancy, breastfeeding, kidney or liver problems, mental health symptoms and other medicines with a clinician or pharmacist. Take fexofenadine-containing products with water rather than fruit juice.

Track when the cough occurs and note nasal symptoms, wheeze, reflux symptoms, workplace exposures and any new medicine. This pattern helps a clinician choose treatment that matches the cause. Do not use montelukast as a substitute for a prescribed quick-relief inhaler during an asthma attack.

Call emergency services for severe breathing difficulty, blue or grey lips, fainting, confusion, or swelling of the tongue or throat. Seek prompt assessment for coughing up blood, chest pain, high fever with marked illness, dehydration, worsening wheeze or a cough that persists or repeatedly interrupts sleep and daily activity.

Clarify whether the cough pattern fits nasal allergy, asthma or reflux; how long to try the medicine; what side effects should trigger stopping it; and whether breathing tests, an inhaler review or another evaluation would be useful.