Applying remedies to the skin

I've bought some homeopathic remedies for a cat from a well respected Homeopath/Animal Health practitioner. According to the directions the remedies (combination remedies) can either be applied directly to the skin between the shoulders or taken orally. This is the first time that I've seen that remedies for internal problems can be applied to the skin. I questioned the homeopath and she confirmed that there is no difference whatsoever in terms of therapeutic action whether taken orally or applied to the skin.According to her it works just as well when applied to the skin of the animal. In fact she said humans can apply remedies to the inside of the wrists too. Would like to hear your inputs please. This is new to me. Thanks.