The first few times i took it, it made me sick. i mean litterally, i would have to throw up at the gym every 15 minutes or so; and it was all just liquid and phlem. i didnt notice any difference in appearance, appetite suppression, or anything. except mood, i was alot more irritable and on edge when i was taking DREN. Its cheap and dosage is low, so it looks appealing; but i would recommend an ECA stack. Ephedrine through BRONKAID pills at your local pharmacy, a can of Red Bull, and a tab of aspirin - 2-3x a day for 4 weeks.
I have found most OTC so callled 'fat burners' make you sick to your stomach. Sure some may give you an energy boost but the only thing you can use it for is sprinting to the bathroom. Never had any problems like this with ephedrine or even Clen.