Do not exceed over 800 mg in any 24 hour period. Seek advice of a doctor before use. Too much caffeine may cause nervousness, irritability, sleeplessness and possibly rapid heartbeat. For occasional use only. Not intended for use as a substitute for sleep. If fatigue or drowsiness persists or continues to occur, consult a physician. Do not use if you are diabetic. As with any dietary supplement, if you are pregnant or nursing a baby, seek the advice of a health professional before using this product.