Symptoms appear gradually and progressively over time. Thought to be a genetic disorder.
- increase in urine output after standing (what a nuisance!)
- migraine headaches
- cold and hands and feet
- orthostatic tachycardia
- orthostatic hypertension
- exaggerated response to isoproterenol infusions
- significantly elevated serum catecholamine levels with serum norepinephrine levels >600 ng/mL (this was found in 29% of patients in a study)
In the hyperadrenergic form of POTS, patients often respond best to agents that block norepinephrine or its effects. One agent that is particularly helpful is clonidine HCI in either pill or patch form. We start the oral form at 0.1 mg PO 1 to 2 times a day and filtrate upward. The patch form of clonidine is quite useful because it provides a constant and continuous amount of the drug for up to 1 week at a time. The combined and β blocking drugs labetalol and carvedilol are quite useful in some patients as pure β-blockers may exacerbate symptoms (because of unopposed receptor stimulation). Methyldopa has been reported to be useful in some patients, as has phenobarbital. In addition, both the SSRIs and norepinephrine reuptake inhibitors are useful in select patients.People who have been diagnosed with this disorder typically have other fmaily members who suffer from it too. I picture long line-ups for the toilets at family reunions.
Here is an interesting article on recent research on what genes may impact POTS...