Autonomic dysfunction also may occur in the setting of acute demyelinating polyneuropathy (Guillain-Barre syndrome). Autonomic symptoms including sinus tachycardia, bradycardia, facial flushing, hypotension, or hypertension; profuse diaphoresis ; or even anhydrosis can occur. In addition, urinary retention also may occur in some patients. The autonomic dysfunction associated with acute demyelinating polyneuropathies often remits after a few weeks. Treatment is supportive and expectant.