I have Postural Orthostatic Tachycardia Syndrome? I have tried remedies the doctors have prescribed, including IV fluids, medicine and exercise. Can you recommend any other treatment?

Dear Hannah:
This condition is often difficult to treat. Fortunately, the vast majority of patients go into remission. It sounds like you have tried some of the first line treatments. I suggest the following:
If you are thin, or tall and thin you would benefit from a workout program to build up your muscles, especially those in your legs. This is usually more effective than support stockings, but it takes time, effort and commitment.
You should increase your salt/sodium intake significantly. Salt is good for you. Fluid intake is important, but your body will not retain it without a corresponding intake of sodium.
As far as drugs are concerned, I usually start with midodrine 5-10 mg 1 to three times a day tailoring the strength and timing to your activity level and the time of day your symptoms are likely to occur.
Beta blockers can help significantly. Very high doses are often required, so unless limited by heart rate or blood pressure constraints, the doses are frequently higher than those used for hypertension.
I have little experience with other drugs, but clonidine (a centrally acting blood pressure medication), benzodiazepines (Valium family), and other neuro psychiatric drugs such as Paxil and Prozac have been tried. In my experience these latter drugs are likely to be of benefit if there is a significant neuropsychiatric issue present.
I nothing above works, an evaluation at a medical center that specializes in these problems would be the next step.
I hope this will help.