Brief Answer:
Please re-post the photograph

Detailed Answer:
Hi.
Thanks for your query.
To recapitulate: Mother/70 is suffering from pain and pus formation in her thumb.
Wants some antibiotic medicines.

Please attach the photograph again is a still not seen on my wall.
Antibiotics are a prescription medicines hence you will please need to valid prescription of a Doctor.
Do you have any left-over antibiotics that suits your Mother?

Added suggestions are:
Elevate the hand above the heart level with support in lying down position so that it helps to reduce the swelling and pain.
Please give her Ibuprofen if it suits her, with food and with PPI like Omeprazole to avoid the acidity.
Consult a Doctor if the pus formation needs let out by incision and drainage and proper dressings.
Apply liq Povidone iodine Betadine locally to the thumb and hand every 8 hours to keep the area sterile.

I hope this answer helsp you, please feel free to ask for further relevant queries if you feel that there is a gap of communication.

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Brief Answer:
Get the white dead skin removed.

Detailed Answer:
Thanks for the picture.
As I can see in the picture provided, there is white dead skin and the excision of this skin helps for early recovery and healing. This can be done by any Doctor under aseptic precaution.
Does not need anesthesia as the dead white skin has no sensations hence can be removed without pain and lets out all the pus.

I am sure this answer helps your Mother on a Happy Mother's day.

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Brief Answer:
Thanks for your appreaciation

Detailed Answer:
You are most welcome.

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