March 9, 2012

Combo combats dizziness

Some patients may need a combo of medications to combat a condition that causes dizziness.


Orthostatic hypotension – a drop in blood pressure upon standing, causing dizziness and near-fainting – is one of the most disabling symptoms of autonomic failure, a disorder of the autonomic nervous system, which controls functions like heart rate, digestion and respiration.

Italo Biaggioni, professor of medicine, and colleagues have previously shown that atomoxetine, an ADHD medication in children, raised blood pressure 50 mmHg on average in patients with autonomic impairment of the central nervous system. But the drug may not work as well in patients with autonomic dysfunction in the peripheral nervous system.

They now report that the combination of yohimbine and atomoxetine – drugs that enhance the activity of the sympathetic nervous system in different ways – significantly increased blood pressure and improved orthostatic tolerance in 17 patients with peripheral autonomic failure; neither drug alone was effective. The results, in the March issue of Hypertension, suggest that this one-two punch therapy may be useful for patients who do not respond to these drugs individually.

The research was supported by grants from the National Institute of Neurological Disorders and Stroke, the National Heart, Lung and Blood Institute, the National Center for Research Resources, and the National Center for Advancing Translational Sciences of the National Institutes of Health.