Certain environmental factors or agents tend to bring about episodes of asthma which are called Triggers.  A patient can remain healthy by avoiding these triggers. It is likely that a patient may have more than one trigger.         Triggersforasthma(b)Triggers responsible for Asthma are

  • Allergens:-  These are substances that people are allergic to.

They are of two types

Indoor allergens  Outdoor allergens
  • House dust mite, dust
  • Animal hair / dander
    (cat, dog, bird)
  • Fungus / Molds
  • Cockroaches
  • Feather / cotton stuffing of pillow and mattress
  • Grass pollen
  • Tree pollen
  • Weed pollen
  • Fungus
  • Dust
  • Infections
  • Viral infections of the nose (causing common cold), throat and lungs can trigger asthma. Usually nasal symptoms like rhinitis (running nose) and sneezing can precede an attack of asthma.
  • Exercise / Cold Air / Sudden changes in temperature and humidity.
  • Environmental factors
  • Fumes and dust
  • Air pollution
  • Tobacco smoke
  • Perfumes and other agents with strong odour like paints or varnishes
  • Chemicals like talcum powder, coal and chalk dust.

Some people get asthma attacks on consuming medication like aspirin, ibuprofen, anesthetic drugs, some anti-hypertensive drugs, preservatives in medications. People with asthma should always consult their doctors before taking any medicine or undergoing any surgery (anesthesia).
Many medicines can bring about an asthma attack. The common ones are

    • Aspirin and other pain killers.
    • Some anti – hypertensives
    • Preservative in certain drugs and coloring agents (tartrazine).
    • Some anesthetic agents given during surgery.
  • Endocrinal factors
    • Pregnancy
    • Menses
  • Psychological factors
    • Emotional stress
    • Anxiety
  • Acidity and other gastric disease
  • Exposure to irritants at job
Biological triggers Chemical triggers
  • Grains/flour – Farmers, millers, bakers
  • Wood dust – Carpenters
  • Cast and pets – Veterinarians
  • pigeons /chickens – Breeding, farming
  • Isocyanate – Paints, plastics, varnishes
  • Formaldehyde – hospital workers
  • Nickel – Plating industry
  • Dyes
  • Trigger in food and drinks
    • Certain food and drinks can bring about an asthma attack ( but it happens rarely).
    • Acidic drinks like cola / other aerated drinks.
    • Metabisulphite containing food like wines, pickles and vinegar.
    • Monosodium glutamate (Ajinamoto salt)