Hay allergy
Allergy to hay, relevant to farming and stables.
About hay allergy
Despite the name, "hay fever" is not an allergy to hay, but hay itself can certainly cause allergic symptoms, which matters greatly for people who farm or keep horses and other livestock. Hay is dried grass, and it typically carries a mixture of allergens: grass pollen trapped when it was cut, plus storage mites and mould spores that multiply as it is stored in barns and stables. Handling and disturbing hay releases these into the air to be inhaled, and in sensitised people they provoke an IgE-mediated allergic reaction. This is a well-recognised occupational issue in agricultural settings.
The usual presentation is allergic rhinitis, with sneezing, a runny or blocked nose and itchy, watery eyes when mucking out, feeding animals or moving bales. Because hay dust is such a potent airway irritant and allergen, it is a common trigger for asthma symptoms, including cough, wheeze and chest tightness, and heavy exposure to mouldy hay can cause more serious lung inflammation in some people. Symptoms are usually not life-threatening, but they can significantly affect anyone whose work involves daily contact.
Reducing exposure helps: keeping hay dry and well stored, damping it down before handling, improving ventilation, wearing a suitable dust mask and washing afterwards. Diagnosis uses skin-prick or specific-IgE tests to identify the underlying pollen, mite or mould sensitivity. Treatment follows the usual ladder of antihistamines and steroid nasal sprays. See a GP if symptoms are persistent, work-limiting, or accompanied by breathlessness.
Common triggers
- Hay and products containing it
Symptoms
- Sneezing and a runny or blocked nose
- Itchy, red or watery eyes
- Itchy throat, nose or ears
- Coughing or wheezing
- Worsening of asthma
Avoidance & management
- Reduce exposure to the trigger where possible
- Keep windows closed during high-exposure periods
- Use air filtration and wash bedding regularly
- Shower and change clothes after exposure
- Use prescribed antihistamines, nasal sprays or preventers
Sources & references
Allergy safety: what everyone should know
Mild-to-moderate reaction signs
- Itching, hives or a raised rash
- Swelling of lips, face or eyes
- Tingling mouth, sneezing, runny nose
- Stomach pain, nausea or vomiting
Anaphylaxis — call 999 (UK) or 112 (EU) immediately
- Difficult or noisy breathing, wheeze, persistent cough
- Swelling of the tongue or tightness in the throat
- Dizziness, collapse, pale and floppy (young children)
- Use an adrenaline auto-injector (e.g. EpiPen) at once if prescribed, then call an ambulance even if symptoms improve
Allergy or intolerance? A true allergy involves the immune system and can escalate quickly; an intolerance (e.g. lactose intolerance) is unpleasant but not life-threatening. The symptoms overlap, so self-diagnosis is unreliable.
Getting tested: home-testing kits based on IgG are not diagnostically valid. If you suspect an allergy, ask a GP for referral to an allergy clinic for skin-prick or specific-IgE testing and a supervised food challenge where appropriate.