Should I give my dog apple cider vinegar?
(Q) Would giving my dog apple cider vinegar get rid of tear stains, and what health benefits does it have?
(A) Vet Roberta Baxter says: There aren't any proven health benefits in giving apple cider vinegar to dogs.
It contains acetic acid and may have actions that aid the management of diabetes and obesity - there's some evidence of this in humans. I don't believe there is any scientific evidence that supports its use in other conditions. There are some potential risks in giving an acidic product of variable potency, with no particular recognised dose rate.
It may also affect the absorption of certain other medicines. I'm all for using supplements that have proven efficacy, but I wouldn't advise you to give apple cider vinegar to your dog, particularly not for tear stains.