K'an makes liquid versions and pills of a number of key formulas. You can also suspend the herbs in a small amount of liquid and just syringe it in down the inside of the dog's cheek, where it will then flow behind the teeth and down the throat. For internal organ pathology, the herbs can be given rectally via enema as well. This is very handy if the animal has an upper GI shut down. Do not use this route for tinctures, however.
Lastly, you can start with a very (even ridiculously) low dose that the dog will tolerate. Sometimes if the formula is right, even these small doses will effect positive changes, resulting in, for example, an eventually improved appetite and a willingness to accept larger doses.
Good luck!
Steve