Dehydration and post nasal drip: what to know

Post nasal drip is the sensation of mucus moving from the back of the nose into the throat. A dry mouth or throat can make that mucus harder to clear and may cause frequent throat clearing, cough, or a sticky feeling. Allergies, a cold, sinus irritation, reflux, and dry air are common possibilities. Dehydration can follow vomiting, diarrhoea, heat exposure, or poor intake, so the two problems may appear together without one fully explaining the other.

Take frequent small sips of water and rest from heat. Saline nasal spray or a gentle saline rinse may loosen mucus; use sterile or previously boiled and cooled water for a rinse and follow the product directions. A humidified room can reduce dryness. Avoid smoke and other irritants. If you have diarrhoea or vomiting, ask a pharmacist about oral rehydration. Do not sharply increase fluids if a clinician has given you a fluid limit.

Get urgent help for severe breathing difficulty, fainting, confusion, inability to swallow fluids, or signs of serious allergic reaction. Contact a clinician if symptoms persist, recur frequently, or come with fever, facial pain, wheezing, blood, or marked dehydration. Dark urine, constipation, or cloudy urine can add useful context, but each may have causes that need separate assessment.

Could allergy, sinus irritation, reflux, or a medicine explain the drip? Is a saline rinse suitable for me? How much should I drink while I am unwell? Do my bowel or urine changes suggest a separate problem?