Clonidine-induced Dysphagia

Abstract

Purpose: Acute colonic pseudo-obstruction (Ogilvie's syndrome) is characterized by cecal and right colonic dilatation without organic, intraluminal obstruction. Clonidine-induced intestinal pseudo-obstruction was first identified over 30 years ago. Its effects on the esophagus have not been described before. We present the first reported case of dysphagia immediately after application of a clonidine transdermal patch. This is a 59-year-old female with a past medical history of hypertension, diabetes, and cerebrovascular accident with residual left-sided weakness who presented with sudden onset dysphagia and an inability to tolerate oral secretions. She had seen her primary care doctor 1 day prior and was prescribed a clonidine transdermal patch for hypertension. The following day, she ate dinner without difficulty but then started experiencing dysphagia 2 hours after applying the clonidine patch. Physical examination did not reveal any new focal neurological deficits. A CT head was performed on admission, which was negative for acute infarction. A barium swallow revealed pooling of contrast in the hypopharynx, however otolaryngological evaluation did not reveal any abnormalities. Upper endoscopy revealed normal esophageal contractility with no upper esophageal sphincter abnormalities. When the clonidine patch was discontinued, the patient regained swallowing capability and was able to tolerate a diet. Clonidine, an α-2 adrenergic agonist, is mainly used as an anti-hypertensive agent. In animal studies, stimulation of α-2 receptors decreases gastrointestinal (GI) motility. Clonidine has been used as an antidiarrheal agent, providing further evidence of its inhibitory effect on the GI tract. We hypothesize that the pathophysiology behind clonidine-nduced dysphagia is similar to its role in intestinal pseudo-obstruction. It may result in a decrease in esophageal peristalsis, or, as seen in our case, have inhibitory effects on the upper esophageal sphincter. We feel that the proximity of onset and resolution of dysphagia to application and discontinuation of the clonidine patch suggests causality.Figure: Normal upper esophageal sphincter.