Desmopressin acutely decreases tachycardia and improves symptoms in the postural tachycardia syndrome
Desmopressin (DDAVP) is an antidiuretic (a drug that acts on the kidneys to decrease urine production). DDAVP increases fluid retention and therefore it was hypothesized that it could be beneficial in the treatment of POTS because many patients have low blood volume.
Compared to placebo, DDAVP improved symptoms, decreased standing heart rate, and decreased the change in heart rate with standing without significantly changing blood pressure.
Because DDAVP increases water reabsorption by the kidneys, future studies will need to be performed to evaluate whether long term use of this medication causes significant side effects such as edema, headaches, or hyponatremia (low sodium concentration in the blood) that could result from chronic free water reabsorption.