Clenbuterol has minimal anabolic effects . It has powerful fat burning properties . Metabolism can increase ( about 10 %) , body temperature by about one half degree up , and also slightly increasing muscle strength . Side effects while taking this medicine is mainly palpitations , trembling hands , excessive sweating , insomnia , in extreme doses headaches or even nausea . These symptoms subside after stopping . It is somewhat hepatotoxic , of course increasing dose also increases its toxicity . When taking this substance is advised to drink plenty of fluids and the last daily dose should be 15 to 16 - o'clock (for sleep) .