Efficiency of droxydopa in pure autonomic failure

Neurogenic orthostatic hypotension (OH) is the main symptom of generalized autonomic failure and often a first sign of pure autonomic failure (PAF). It involves chronic failure of the autonomic nervous system, characterized by orthostatic reduction of blood pressure and sympathetic denervation of the cardiovascular system, but also of the sudomotor and neuroendocrine regulation. The presence of Lewy bodies in autonomic ganglia indicates an alpha-synucleinopathy with exclusive affection of the peripheral nervous system. Reduced serum noradrenaline concenctrations are found, pointing towards dysregulation of noradrenaline neurotransmission.

L-dihydroxyphenylserine (droxydopa, L-DOPS) has a similar chemical structure as noradrenaline, with an additional carboxyl group, and is a physiological precursor of noradrenaline.

In our case of a female patient aged 75 years with recurrent syncopes, detection of reversed sympathetic innervation in MIBG-SPECT, pathological quantitative sudomotor axon reflex test, small fiber polyneuropathy in skin biopsy, and evidence of severe OH in 70° tilting table examination, therapeutic efficiency of droxydopa was confirmed. We found a significant hypotension after erecting from an average of 106/59mmHg in lying prone to an average of 84/59mmHg in standing position. With medication with 200mg L-DOPS, we found an average pressure of 126/78mmHg in lying position and 118/86mmHg in standing position. Our patient is comfortable with no complaints with a medication of 2×200mg L-DOPS. Problems about prescription of this orphan drug in Germany are in discussion.