Brief Answer:
Please meet your dentist

Detailed Answer:
Hello

The commonest cause for glandular swelling under the chin would be due to dental caries or infected gums and therefore it is advisable to get a dental check up done.

The sinus drainage causing cough needs to be evaluated further with a ct scan and nasal endoscopy.

In my patients I would normally start on a course of antibiotics like amoxicillin which will take care of the glandular swelling and the sinus drainage.

Please discuss this with your doctor

Thanks

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