Dust or house mites, molds, outdoor pollen, animal dander, cockroach feces, and feathers
Particularly exercise in cold or dry air
Firsthand and secondhand tobacco smoke, perfumes, wood smoke, cleaning products, scented candles, outdoor air pollution, strong odors, and irritating fumes
Viral respiratory infections*
Respiratory syncytial virus Respiratory Syncytial Virus (RSV) Infection and Human Metapneumovirus Infection Respiratory syncytial virus infection and human metapneumovirus infection cause upper and sometimes lower respiratory tract infections. Respiratory syncytial virus is a very common cause of... read more , rhinovirus Common Cold The common cold is a viral infection of the lining of the nose, sinuses, and throat. Many different viruses cause colds. Usually, colds are spread when a person's hands come in contact with... read more , parainfluenza virus infection
Emotions (such as anxiety, anger, and excitement), aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs), and gastroesophageal reflux Gastroesophageal Reflux in Children Gastroesophageal reflux is the backward movement of food and acid from the stomach into the esophagus and sometimes into the mouth. Reflux may be caused by the infant’s position during feeding... read more
* Viral infections are the most common triggers in children.