Brief Answer:
Visit a ENT specialist...

Detailed Answer:
Hi,

Persistently congested nose is generally due to allergic causes. Occasionally a pre-existing nasal conditions can contribute to her symptoms. I understand you have tried various medication; but without identifying the cause medical therapy is only going to be a temporary solution.

Since most children outgrow this problem; if I were to be your treating doctor I would suggest you to keep her warm and protected against seasonal changes, dust and common house hold allergens. Consult an ENT specialist to identify if there are other pre-existing nasal condition. He/she can also prescribe you antihistamine nasal spray which can benefit her.

In brief, this is going to be little difficult to manage. However with patience, good precautions and help of specialist, she will outgrow her problem.

Hope this helps. Write back for clarifications.

Regards

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