Brief Answer:
There is no risk in swallowing a strand of hair

Detailed Answer:
Hi XXXXX,
Thanks for writing in to us.

I have read through your query in detail.
Please find my observations below.

1. The entire airway beginning from the nose and till the lungs is a specifically designed tract adapted for respiration. There are small cilia lining the airway which start in the nose and continue till the lung. This cilia keeps the airway clear of mucus and dirt with its regular movement.

2. Let us say that the hair enters through the mouth and reaches the throat, even then, the moment it reaches the throat, the cilia over there are hyperactive and along with ciliary motion there is also cough reflex that is triggered.

4. Sneeze is a reflex action in which any irritant is forcefully thrown out of the nose and when small impurities enter the nasal passage and start irritating the cilia then you will sneeze and it is expelled out.

5. The cough is a reflex mechanism by which the throat is cleared of any obstruction. The tongue is also sensitive at the feel of a hair in the mouth and any hair reaching the throat is thrown out by a violent cough.

6. It is important to know that there is regular generation of mucus in the throat and this also to a certain extent prevents the forward passage of a substance like a hair. A person having a hair in the throat might experience a cough, though every person will not have it.

7. Taking a worse case scenario, it might get swallowed in the throat leading to the esophagus. When this happens then there will be a tingling sensation and a reflex gag which will again try to throw the hair out from the mouth. If that does not happen then the single strand of hair is passed on to the stomach and then comes out as feces in a day.

Hope this answers your question. Please feel free to correct any oversight in my interpretation of your problems and discuss them in detail as per your requirements.

Hope your query is answered.
Do write back if you have any doubts.

Regards,
Dr.Vivek

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