Two of my dear friends swear by this concoction, taken when early
signs of  mastitis appear:
   1 Tablespoon apple cider vinegar in grape juice (or other palatable
juice), taken 1 to 2 times daily until symptoms resolve.

For what it's worth, since they have begun this regimen, neither has
had a trip to the clinic for antibiotics.  They both had frequent
bouts of it prior to starting this.  They have both learned to swallow
without smelling or tasting, as it's...rather unpleasant!

Kathryn Colestock-Burke, CNM, LC
Austin, Minnesota   (Gorgeous sunny days in 70s, perfect nights in
50s, the sumac is turning red...)