Brief Answer:
Detailed answer below.

Detailed Answer:
Hi,
Thanks for your query. I have read it and understood your concern.
Presence of water in ear, dizziness and nausea after Neomycin ear drops, suggests some inflammation inside the ear. Clogging of ear, possibly due to eustachian tube block or inflammation /infection may be the cause. In few cases, inner ear may also be affected.
Such condition may need antibiotics with anti inflammatory drugs along with anti allergic drugs to relieve root cause. A detailed physical ear examination followed by investigations as per need are necessary to know the exact cause of the problem. I would therefore suggest a consultation by an ENT specialist earliest and get more specified and personal prescription for complete relief.
You can start with home care like vapor inhalation, saline gargles, over the counter anti inflammatory drug like Tablet Ibuprofen 200 mg twice a day after food (dose suitable for her age &health) and a pill of cetrizine 5mg at bed time.
Avoid blowing of nose or forceful cough.
I hope that is helpful to your mother. Any follow up query is welcome.
Thanks

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