The US Food and Drug Administration has added to its list of dozens of weight-loss products - available in stores and online - that contain undeclared pharmaceutical ingredients.

The new naughties contain drugs like fenproporex, an amphetamine derivative not approved in the US, and fluoxetine, better known as Prozac, the antidepressant. This extra stuff can produce unpleasant and even dangerous effects.

Here's the FAQ on the list of products plus the contaminants and their effects.