I apologize that no one has responded to your question sooner. Different experts come online at various times. I just logged on and saw your question. My name is ***** ***** I’m a biologist with a special interest in alternative medicine for pets. I'm sorry to hear of Spike's diagnosis.
The reason you can't find a dosage of Berberine for cats is that no dosages have been established. Some studies have been done on cats to determine possible side effects. The lowest dose used was 5 mg per kg of body weight. A kilogram is about 2 pounds. At that dose, the cats suffered temporary neurological symptoms that resolved on their own. That included loss of control of bladder and bowels, and retching.
The Berberine was injected because it tastes so awful most cats won't eat it, even when mixed with something tasty. You can read the whole study here:
I suspect you got your information about Berberine from human alternative medicine sites. There is some evidence that it can reduce breast tumors in women. However, in a study with rats, it was found to cause liver tumors. It's most common use if for diabetes and it does help with that. If you decide to use it with Spike, I would go with the lowest amount from the cat study, which is the amount I gave you above. You can crush a tablet and mix it with water. Then you'll have to use a syringe to put it in his mouth. You'll most likely have to hold his mouth shut and wait fro him to swallow. Some cats will take it if it's mixed with tuna, but that doesn't work for most.
One of the most promising holistic cancer therapies is the use of medicinal mushrooms. Certain species of mushrooms have been found to suppress the growth of cancer cells and boost the immune system. Here is a source of a mushroom supplement made just for pets:
I highly recommend that you take a look at the following link. It is a directory of available information for owners of cats with cancer. There are dozens of links given for supplements alone, and the information comes from reliable sources. I couldn't begin to give you a fraction of what you'll find there:
If you have more questions, just let me know. I hope that whatever you do, it will work out well for Spike.
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