Elaine,

The heart-racing is definitely a very unusual response to Oxy-Powder.  It could be a result of toxins that are generated from parasitic or fungal die-off as the result of cleansing and the introduction of oxygen.  It would be very unusual, but sometimes people that are susceptible to anxiety have unusual responses to an influx of toxins.  Some of the individual ingredients in Oxy-Powder are actually used as supplements in order to maintain heart health.  It is important to distinguish whether the heart racing is caused by actually taking the colon cleanser or whether it is only occur during the same period of time. People can experience palpitations from poor adrenal control, stress, anxiety, medications, poor nutritional status, and a number of other things.  It may be a good idea to stop taking it for a few days and then re-starting to see if the palpitations cease and if they begin again.  This is a fairly easy way of establishing a reasonable correlation between the product and the symptom.  Also, if it is due to die-off, it would not be unusual to feel fatigued, experience joint/muscle aches, have a minor rash, feel "foggy," experience trouble sleeping, or feel nauseated.  These describe a few of the other possible symptoms that can be related to detoxification and the elimination of parasites.