I don't think these products work very well, at least not the ones I have tried. I find the best solution for temporary plumping is to vigorously exfoliate your lips using a damp washcloth or toothbrush for a minute or two (you can then apply lipstick or gloss or whatever you would normally put on). This will plump your lips slightly and also bring out or slightly deepen your natural color. It also has the added benefit of softening and ridding your lips of any flakiness or chapping -- not to mention it costs nothing, and you get to keep potentially irritating substances or chemicals off your lips.