The products against parasites are listed in order of the most important (and sometimes best) to the least important. They are listed alphabetically. I will list my recommendations as a supplement for the most important parasites as well as a recommendation for the least important ones. I have included my recommendations with some comments as to whether or not they work or are appropriate.
There are many ways to fight parasites, but my most important advice for you is to understand what is going on when you feel a parasite biting, and to use a product on a person that is most likely to protect you from infection. There is no "magic bullet" for parasites. The best way to find out what works for you and your situation is to do a little research. You may discover that a parasite is a problem, but if you have a hard time understanding that then you can use my recommendations to learn more about parasites, how to treat them, and how to prevent them. The advice above comes from my experience treating and finding ways to treat parasitic infections. I don't want you to just "take my word" for it, but I know my recommendations are the best and most up to date.