Brief Answer:
Supportive care

Detailed Answer:
Thank you for asking

I read your question and i understand your concern. Difficulty breathing out via mouth and with no problem via nose needs further anatomical correlation. Ideally its desirable to breath through nose in and out as that keeps the air humid and warm and is the desired pathway. Had there been any structural obstruction for breathing it would have been in both directions both nose and mouth.

Now your otolaryngologist advising omeprazole which is an antacid indicates its feeling of something stuck in throat due to GERD which is indirectly likely due to obesity, smoking, or any other trigger in diet. Modifying diet lifestyle , taking antacids, losing weight, eating small frequent meals may help. Any how get evaluated for other inflammatory disorders of airways like asthma, allergies or infections that may be causing breathing discomfort. Meanwhile practice breathing though nose and its wise to use this way any ways.

I hope it helps. Take good care of yourself and dont forget to close the discussion please.

Regards XXXXXXX

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