Can rhus tox 30c be given to dogs?

You should not give your dog any medication that hasn't been prescribed or recommended by your dog's Vet. Substances which are safe for humans are not necessarily safe, and can sometimes be deadly, for dogs. Things like chocolate, grapes, acetaminophen, decongestants, etc., etc. are fine for humans, but can be very toxic to dogs. If you're interested in using homeopathic remedies, consider finding a Vet which includes alternative medicines in their practice.