View clinical trials related to Dysautonomia, Familial.
Filter by:Evaluate the effects of bronchodilator therapy on respiratory function. Our overall goal is to determine whether, in patients with familial dysautonomia (FD), there is a component of airway obstruction that is reversible. To this end, we will evaluate airway resistance before and after receiving the anti-cholinergic ipratropium (Atrovent ®) and the beta-2-agonist albuterol (ProVentil®/Ventolin®). We predict that the response to either drug will depend on the underlying level of sympathetic and parasympathetic activity and airway tone. We will then determine the cardiovascular effects of inhaled ipratropium and albuterol in patients with FD. Because patients with FD have fewer sympathetic neurons and denervation supersenstivity, we predict that following albuterol inhalation, there will be non-selective activation of alpha-1-adrenergic receptors. Furthermore, because of a congenital defect in the afferent baroreceptor neurons that sense blood pressure, we suspect that the resulting vasoconstriction will be unopposed leading to a pressor effect. We hypothesize that inhalation of the anti-cholinergic ipratopium will produce little rise in heart rate, due to the extent of parasympathetic denervation to the heart.
This is a pilot clinical trial of carbidopa to treat disabling attacks of nausea and vomiting in patients with familial dysautonomia (FD, also known as Riley Day syndrome or hereditary sensory and autonomic neuropathy type III). FD is a rare autosomal recessive disease in which the growth and development of selective nerves is impaired. Patients with FD suffer recurrent uncontrollable nausea and vomiting crises accompanied by skin flushing, tachycardia and arterial hypertension. Current treatments of nausea are ineffective or have intolerable side sides. Our long-term goal is to treat nausea effectively and without side effects, a therapeutic intervention that would markedly improve the quality of life of patients with FD. The investigators have recently found that resting plasma dopamine levels are high in patients with FD and increase up to 40-fold during nausea and vomiting attacks. This led us to postulate that stimulation of dopamine receptors in the chemoreceptor trigger zone of the brainstem is the likely mechanism of vomiting. Carbidopa is a reversible competitive inhibitor of aromatic L-amino acid decarboxylase (also known as dopa-decarboxylase) that cannot cross the blood brain barrier. It has been used successfully for many years to block the extracerebral synthesis of dopamine and avoid nausea and vomiting in patients with Parkinson's disease taking levodopa. The investigators reasoned that carbidopa could have a similar antiemetic effect in patients with FD. The investigators propose to conduct a pilot trial to assess the safety, tolerability and efficacy of carbidopa for the treatment of nausea in patients with FD. The pilot trial will recruit 25 patients with FD who complain of severe nausea that affects their quality of life. The trial will be divided into two consecutive, but independent parts. Part 1, will address the safety and tolerability of carbidopa in patients with FD using an open-label dose titration phase followed by 4-weeks of open-label treatment. Part 2, will address the efficacy of carbidopa for the treatment of nausea in patients with FD using a randomized, placebo controlled, double blind, 4-week cross over design. The investigators hope to demonstrate that carbidopa is a safe, well-tolerated drug that blocks the peripheral formation of dopamine and thus prevents dopamine-induced nausea and vomiting attacks in patients with FD.