Actually, Zocar is filtered through the liver and may affect liver enzymes. To my knowledge, Zocar has absolutely no effect on the kidneys. I take Lipitor which is similar to zocar. It brought my cholesterol down well. ( I was not having problems with my trig., though).
Regarding the stomach pain, new drugs often cause GI/stomach problems initially. Can you check the pharmacy info that came with it? Most likely GI problems are listed and sometimes, if you are having trouble, it might be good to take Zocar on a full stomach, and see how that goes.
In my view, statins, such as zocar are generally safe and do a good job lowering blood fats as well as keeping arteries healthy by lowering inflammation as well. I would try to stay on it for a couple of mths and see if it has helped your trig. at your next lab draw.