Right after we adopted Dixie 4 years ago, she started losing hair between her shoulders. Over 6 or so months, it gradually progressed to the point that she had VERY THIN (she wished it was longer so she could try a comb over) on her ENTIRE TOP 2/3 of her body.
We had been working with the vet non-stop with no results. After MUCH testing, it was finally decided that she had ringworm although it did not respond to any of the treatments she was given (two rounds of oral meds which are terrible on the liver, 8 weeks of weekly sulfur dips, topical shampoos, etc).
The vet had finally given up when I found some information on the use of tea tree oil for treatment of MANY different skin ailments.
IT IS IMPORTANT TO KNOW THAT TEA TREE OIL CAN BE TOXIC TO DOGS IF APPLIED STRAIGHT OR IN A VERY STRONG SOLUTION....
With that being said...
I did quite a bit of reading and searching for information on the use of tea tree oil with dogs and after we had tried just about everything else opted to try it.
We mixed about 1/4 teaspoon of tea tree oil into 16-20 oz of water and put that into a garden sprayer (the kind you pump to pressurize). We would take Dixie outside and give her a healthy spray all over the effected areas (yeah, basically her whole body) avoiding her head.
Within 2 weeks of daily spraying, she had new hair growth. Now, if we see even a small thinning patch on her (the vet said that ringworm fungus actually lives in the dirt and is almost impossible to get rid of...), she gets a couple of days of spray and is just fine.
Tea tree oil is said to be very good for many skin problems and it was all but a miracle cure for Dixie and her itchy, bald skin, but please note with dogs that less is better than more.