Each 100 mg BOSULIF tablet contains 103.40 mg of bosutinib monohydrate, equivalent to 100 mg of bosutinib; each 500 mg BOSULIF tablet contains 516.98 mg of bosutinib monohydrate, equivalent to 500 mg of bosutinib.
Having said that, If your dog is itching and scratching all year long, then it's most likely due to either a food allergy or an allergy to something that is present all year such as dust mites or possibly even mange. In either case, you'll probably need more help to determine the cause which you can find here.
If it's a food allergy, your vet can advise you of dietary changes or supplementation that may stop the itch. Sarcoptic mange, also known as scabies, is caused by mites and drives your dog crazy with itching. Besides hair loss, your dog's skin is inflamed and sores appear. Be careful -- this type of mange can affect humans. Demodetic mange is less of a problem, but appears to be hereditary in certain breeds.