What causes sneezing?
Sneezing or sternutation is the act of expelling a sudden and uncontrollable burst of air through the nose and mouth. Sneezing can occur for a variety of reasons that have in common an irritation of the lining (mucous membranes) of the nose or throat.
Sneezing cannot occur during sleep due to REM atonia – a bodily state where motor neurons are not stimulated and reflex signals are not relayed to the brain.
Sufficient external stimulants, however, may cause a person to wake from sleep to sneeze, but any sneezing occurring afterwards would take place with a partially awake status at minimum.
Sneezing – Mechanism of action
Sneezing typically occurs when foreign particles or sufficient external stimulants pass through the nasal hairs to reach the nasal mucosa. This triggers the release of histamines, which irritate the nerve cells in the nose, resulting in signals being sent to the brain to initiate the sneeze through the trigeminal nerve network.
The brain then relates this initial signal, activates the pharyngeal and tracheal muscles and creates a large opening of the nasal and oral cavities, resulting in a powerful release of air and bioparticles.
The powerful nature of a sneeze is attributed to its involvement of numerous organs of the upper body – it is a reflexive response involving the face, throat, and chest muscles. Sneezing is also triggered by sinus nerve stimulation caused by nasal congestion and allergies.
The neural regions involved in the sneeze reflex are located in the brainstem along the ventromedial part of the spinal trigeminal nucleus and the adjacent pontine-medullary lateral reticular formation.
This region appears to control the epipharyngeal, intrinsic laryngeal and respiratory muscles, and the combined activity of these muscles serve as the basis for the generation of a sneeze.
Causes of sneezing
- Air Pollutants
- Cold Air
- Drug Withdrawal
- Exposure to Bright Light
- Spicy Foods
- Strong Emotions
Sneezing can generally be managed by avoiding allergens or triggers. However, medical intervention may be needed when the symptoms do not subside with preventive measures.
Sneezing can be managed in several ways:
- Sneezing, and other symptoms triggered by allergies can be treated with allergy medications
- Allergy shots can help in preventing future allergic reactions.
- Systemic antibiotics can be used for patients with secondary bacterial infection (developed during or after a viral infection).
- Agent-specific antibiotics are used for patients with rhinitis secondary to specific bacteria.
- For fulminant fungal infections, diagnosis followed by immediate treatment is vital.
- The treatment for sneezing caused by viral infections such as the common cold or flu has limited options as antibiotics remain ineffective in these cases. However, the use of antipyretics and decongestants may provide mild symptomatic relief.