Northera (Droxidopa) Available for Treatment of Neurogenic Orthostatic Hypotension
Only FDA-approved therapy for NOH
Northera (droxidopa, Lundbeck) oral capsules are now available for health care providers to prescribe in the U.S., according to a recent announcement.
The norepinephrine prodrug was approved by the FDA in February 2014 for the treatment of orthostatic dizziness, lightheadedness, or the “feeling that you are about to black out” in adult patients with symptomatic neurogenic orthostatic hypotension (NOH) caused by primary autonomic failure (e.g., Parkinson’s disease, multiple-system atrophy, or pure autonomic failure), by dopamine beta-hydroxylase deficiency, or by nondiabetic autonomic neuropathy.
The effectiveness of Northera beyond 2 weeks of treatment has not been demonstrated. The continued effectiveness of the drug should be assessed periodically.
Northera is the only FDA-approved treatment for NOH and carries a boxed warning regarding supine hypertension. Other serious risks, including hyperpyrexia, confusion, cardiovascular risk, and allergic reactions, are associated with use of the drug.
The most common adverse events observed in patients treated with droxidopa in controlled clinical trials included headache, dizziness, nausea, and hypertension.
Symptomatic NOH is a rare autonomic nervous system disorder associated with the failure to release adequate amounts of norepinephrine upon standing. NOH is caused by an underlying autonomic neurologic disorder, such as Parkinson’s disease, multiple-system atrophy, or pure autonomic failure. Norepinephrine deficiency may result in the inability to maintain adequate blood pressure and blood flow to the brain upon standing, resulting in dizziness, lightheadedness, and the “feeling that you are about to black out.”
The precise mechanism of action of droxidopa in the treatment of NOH is unknown. Droxidopa is a synthetic amino acid analog that is directly metabolized to norepinephrine by dopa-decarboxylase, which is extensively distributed throughout the body. Droxidopa is believed to exert its pharmacologic effects through norepinephrine and not through the parent molecule or other metabolites. Norepinephrine increases blood pressure by inducing peripheral arterial and venous vasoconstriction. Droxidopa in humans induces small and transient increases in plasma norepinephrine.