Many people develop candida as a result of the parasite shifting the bowel ecology. So removing parasites is the first step, but you really need to know which parasites you have before embarking on a treatment journey. Every parasite grouping requires different strategies, for instance you well may be suffering with a protozoa infection in which case herbal parasite formulas are unlikely to help. They are more designed for worm infections, although some manufacturers will claim to kill protozoa, that would be a suspect promise.
The test from Metametrix (GI Effects Stool) is the best test around and testing thru other methods is hit or miss at best. They can identify the problem then you can tailor the correct treatment strategy.