What causes a rash on a dogs skin and what is the cure?

Sometimes it can be from flea bites, also dogs get hot spots and allergic reactions and some rashes come from other things. If your dog has alot of rashes on his body go to the vet. I find that sulfodene helps, and also sulfodene shampoo. Wash the area with mild soap plain Ivory or Neutrogena clear bar or baby shampoo Keep in mind you don't want your dog to be able to lick these areas that have the rash. You could try some of these remedies. I am not a vet, I am only giving advise to best of my knowledge with pets. Is the rash bleeding? Is rash sore to touch to dog? If no bleeding or oozing sores can try this Apply a paste of baking soda or dab a bit of vinegar on it. Try some bactine ointment or spray (carefull with the spray!) or Gold Bond Cream or spray, see if it heals up abit after a day or two, you may want to try a little benedryl gel If no improvement take the doggie to the vet. This is all I can think of at the moment, hope all is well with your doggie