Balsam of Peru allergy
Contact allergy to balsam of Peru, a fragrance marker.
About balsam of peru allergy
Balsam of Peru is a natural resin from the *Myroxylon* tree, used historically in perfumes, flavourings and topical medicines. In patch testing it acts as a useful marker for fragrance sensitivity, because it contains dozens of aromatic compounds also found in scented products. Allergy to it is a delayed, type IV allergic contact dermatitis, so the rash usually develops a day or two after skin contact rather than immediately. It is one of the more common positive results on standard patch test series, and can affect anyone regularly exposed to perfumed cosmetics, toiletries or certain ointments.
The rash is typically itchy, red and sometimes scaly or blistered, appearing where scented products are applied, such as the face, neck, underarms and hands. Because balsam of Peru shares constituents with many fragrances, people who react to it often also react to the fragrance mix and to related botanical extracts; some also notice flares from strongly flavoured foods and spices, though this is variable and less predictable.
Diagnosis rests on patch testing by a dermatologist, not skin-prick testing. The mainstay of management is reading labels and avoiding fragranced products, choosing items marked fragrance-free rather than simply unscented. Barrier care with plain emollients helps restore the skin, and topical steroids may be advised for flares. See your GP or a dermatologist if a scented-product rash keeps returning or is hard to control.
Common triggers
- Balsam of Peru and products containing it
Symptoms
- Red, itchy rash (contact dermatitis)
- Dry, cracked or scaly skin
- Blistering or weeping in severe cases
- Burning or stinging where skin met the trigger
Avoidance & management
- Avoid skin contact with the trigger
- Wear gloves or use barrier creams
- Choose products labelled free from the allergen
- Rinse skin promptly after contact
- Use emollients or prescribed steroid creams
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.