Is hay fever worse in the morning or evening?
Hay fever can be worse at either time of day depending on which pollen you're allergic to and local weather conditions. There is no single answer because different plants release pollen at different times—for example, grass pollen peaks around 7:30am whilst birch pollen is released in the afternoon. For some people, symptoms are actually worse in the evening due to a "pollen shower" effect, where pollen grains drift back down to ground level as air cools after a warm day.
Key points:
- Grass pollen tends to cause worse morning symptoms, whilst tree pollen like birch causes worse afternoon and evening symptoms
- Evening symptoms can worsen in cities where buildings release heat, slowing air cooling and prolonging the pollen shower effect
- Morning symptoms may be triggered by pollen released overnight that has settled on bedding, curtains or pets
- Weather conditions like temperature, wind and rain significantly affect when pollen counts peak throughout the day
This text has been fact-checked for accuracy by medino's clinical team.