Christmas tree allergy
\"Christmas tree syndrome\" from mould and terpenes on conifers.
About christmas tree allergy
So-called "Christmas tree syndrome" describes a cluster of allergy-type symptoms that some people notice after a real conifer is brought indoors. The tree itself is rarely the true allergen; instead, it carries mould spores that multiply in the warm home, along with pollen, dust and naturally fragrant terpene oils from the sap and needles. Sensitised people can react through an IgE-mediated allergic response to the moulds and pollen, while the terpene scents act more as airway irritants. It is a recognised, if uncommon, seasonal complaint that appears in the weeks around Christmas when trees are on display.
The usual presentation is allergic rhinitis: sneezing, a runny or congested nose and itchy, watering eyes that build up over the days a tree is in the room. People with asthma may notice more coughing or wheeze, and those with eczema can find their skin flares, partly from handling sap and needles. Symptoms are generally mild and settle once the tree is removed, though they can be a nuisance during the festive period.
Helpful measures include hosing down and drying a tree before bringing it indoors, limiting how long it stays up, using an air filter, and considering an artificial tree if reactions recur each year. Diagnosis, where needed, uses skin-prick or specific-IgE testing to identify the underlying mould or pollen sensitivity. Symptoms respond to the usual antihistamines and steroid nasal sprays. See a GP if festive symptoms are severe, keep recurring, or trigger troublesome asthma.
Common triggers
- Christmas tree 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.