Brief Answer:
Need investigation, get chets X ray and sputum tested for tuberculosis

Detailed Answer:
Hello,

Persistent dry cough could be due to allergy or could be due to tuberculosis or some other condition.

We need to identify the exact cause, and it needs proper and complete physical examination, complete history and investigations like X-Ray of the chest., CT scan of the chest, sputum test for TB among others like CBC, CRP etc.

Please visit your local doctor or pulmonologist and undergo these tests.

Once the cause is identified, we can determine what best treatment is available in your case.

Hope that answers your query,

Best regards

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