Not meaning to sound negative, but sometimes over the counter drugs and herbal medicines can indeed hurt. Most medicines have contra-indications and side effects. Contra-indications are medical conditions that specify when you shouldn't take a particular medication. Some off the shelf medications can have bad effects when combined with prescription drugs. Sometimes, the off the shelf medicine can interfere with the prescription drug, making it less effective. Sometimes, the combination can have adverse reactions.

After seeing what happened to my friend Clyde with Avonex after taking an experimental treatment, I'd want to consult with a doctor before mixing Avonex with anything.