Upon arising I have a heart
beat of 60 and feel a little heady. After breakfast, with one cup of coffee and a piece of bread with jelly, my heart rate climbs, within an hour, to 70. I didn't used to feel dizzy upon arising. I'm a 70-yr.-old male, healthy and active, play tennis, no medications. I've recently been diagnosed with low platelet count (110,000). What are the possible diagnoses? Is low blood sugar one?