If it is columnaris the fish scales can sometimes swell.
Myxazin by waterlife only effective on a mild case of columnaris. I would also lower your tank temp as columnaris thrives at higher temps.
Link to columnaris,
http
/www.petfish.net/articles/Bettas/columnaris.php
Columnaris
>The hospital tank should be heated to approx. 74 degrees. 76 and above is the ideal breeding temperature for columnaris. Though there is some dispute over lowering the temperature, my experience has been that 72 is too low for the medication to work rapidly, 76+ causes the disease to breed more rapidly than the anti-biotic can kill, and 74 is "just right." Remember to keep this temperature stable.
Text (c) Lauren Weeks
Myxazin by waterlife only effective on a mild case of columnaris. I would also lower your tank temp as columnaris thrives at higher temps.
Link to columnaris,
http

Columnaris
>The hospital tank should be heated to approx. 74 degrees. 76 and above is the ideal breeding temperature for columnaris. Though there is some dispute over lowering the temperature, my experience has been that 72 is too low for the medication to work rapidly, 76+ causes the disease to breed more rapidly than the anti-biotic can kill, and 74 is "just right." Remember to keep this temperature stable.
Text (c) Lauren Weeks