Lying flat is usually the answer: mucus from your nose drips down the back of your throat, and stomach acid travels upward more easily, and both set off the cough reflex.
The NHS names both post-nasal drip and acid reflux as common cough causes, and notes reflux symptoms worsen when you lie down. Allergies can add a third push. Most coughs clear on their own within 3 to 4 weeks. Pymander is a free AI doctor, 24/7 by text, that can help you work out which mechanism is yours.
What to do
Common questions
Why is my cough worse at night?
Gravity does most of the damage. When you lie flat, mucus from your nose and sinuses drips down the back of your throat instead of draining forward, and that drip triggers the cough reflex - the NHS lists mucus dripping down the throat from the back of the nose as a common cough cause. The second mechanism is reflux: stomach acid travels upward far more easily when you are horizontal, and the NHS notes heartburn symptoms get worse when lying down; acid irritating the airway produces a dry, tickly cough. Allergies add to it, since bedding collects dust. What helps tonight: prop your head and shoulders up on extra pillows, sip warm water or hot lemon and honey, and skip food in the 3 to 4 hours before bed if reflux is your pattern. Most coughs clear within 3 to 4 weeks on their own. See a GP if yours lasts more than 3 weeks, you are losing weight for no reason, or the cough is very bad or quickly getting worse. Pymander is a free AI doctor, 24/7 by text, that can help you sort drip from reflux from infection.