I don't have a medical condition, i have been experiencing my heart rate standing out of bed or when anxious to be 100-145. why? doc isn't cocerned.

Anxiety: can definitely increase your heart rate to those levels. In addition, if you don't drink enough fluids, you could experience heart rate increases with standing. If you are concerned, ask your doctor if he would do an EKG just to be sure everything is OK. Hope this helps!

Dehydrated?: One reason the heart rate increases on standing is if you have not been taking in enough fluids. Make sure to drink at least 8 large glasses of water daily. Have your doctor check your blood pressure laying, sitting and standing if you still don't improve.

Palpitations: What you are describing sounds like palpitations. That is great you have already been assessed by your own physician. Sometimes, anxiety or a panic attack can cause your heart to speed up - in those cases it is best to treat the underlying anxiety. Other times a fast heart rate can be indicative of an arrhythmia. Your primary doctor should perform an EKG and simple blood tests for a workup.