Hay Fever Fatigue

Yes – hay fever can absolutely cause fatigue. Seasonal allergies don’t just affect the nose and eyes; they can make people feel physically and mentally drained.

Common reasons include:

• Poor sleep – nasal congestion, sneezing, itchy eyes, and postnasal drip often disturb sleep quality.
• Constant immune activation – your body releases histamine and inflammatory chemicals in response to pollen, which can leave you feeling tired and “foggy”.
• Sinus pressure and headaches – ongoing inflammation can feel exhausting.
• Antihistamines – some allergy medications, especially older ones like chlorphenamine (Piriton), can cause drowsiness.
• Reduced concentration – many people describe “hay fever brain fog”, with low energy and poor focus during high pollen periods.

Typical symptoms alongside fatigue can include:

• Sneezing
• Itchy eyes, nose, or throat
• Runny or blocked nose
• Headaches
• Feeling sluggish or unmotivated

If fatigue is severe, persistent, or occurring outside allergy season, it’s worth considering other causes too, such as:

• Iron deficiency
• Low vitamin D
• Thyroid problems
• Sleep apnoea
• Viral illness
• Stress or burnout

At OneMedicine, fatigue during allergy season is something commonly seen in patients with moderate to severe hay fever, particularly during high tree and grass pollen periods in the UK.