Brief Answer: As below: Detailed Answer: Hi, Thank you for your query. 1. The lump in the nostril of a 5 year old may be a DNS (Deviated Nasal Septum) or a hypertrophied nasal turbinate. 2. Get a nasal examination done to confirm this and rule out any foreign body, polyps or rare conditions such as meningoceles, benign growths and so on. I am assuming that he has no history of nasal bleeding (epistaxis), nasal discharge, vision problems or headaches. 3. Another common cause for nasal obstruction in this age group is hypertrophied adenoids. Get an X-ray Skull, lateral view for adenoids done, especially if he has a history of mouth breathing or snoring. 4. Medication will depend upon the exact examination findings. You may follow up here with the clinical examination notes and investigation reports for further treatment advice. I hope I have answered your query. If you have any further questions I will be available to answer them. Regards.

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