I have pots and sometimes when i experience a fast heart rate, i get an instant intense buzzing all over even if i keep my breathing very slow. due to fast hr, adrenaline, or a different cause?

Check out these: Links. I presume your dr has checked u for thyroid disorder and arrythmias. Take care and god bless u! http://www.Ninds.Nih.Gov/disorders/postural_tachycardia_syndrome/postural_tachycardia_syndrome.Htm.

Possibly related.: Patients with postural tachycardia syndrome (pots) report dizziness, lightheadedness, weakness, blurred vision, and fatigue upon standing.