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Paper text:
sodium picosulfate / magnesium citrate ( sp / mc ) powder has been widely used for colon cleansing because it has an acceptable taste and a small volume of liquid is required after dissolving it .
the effectiveness , safety , and ease of administration of this orange - flavored powder are well established .
adverse effects are rare in clinical practice , although it may induce mucosal inflammation . here
, we report the case of a patient who directly ingested sp / mc powder without first dissolving it in water , resulting in severe mucosal injury that extended from the oral cavity to the upper esophagus and caused airway compromise .
a 59-year - old man was brought to the emergency department ( ed ) in an ambulance with a chief complaint of sore throat .
he was scheduled to undergo colonoscopy that day , and 2 h prior , he had unintentionally ingested a pack of undissolved sp / mc powder ( picolight powder ; pharmbio korea co. , seoul , korea ) that had been prescribed for bowel evacuation . upon arrival in the ed , he was hemodynamically stable and did not have respiratory distress , but he complained of progressive hoarseness .
the emergency physician noted gross mucosal injury of the oropharynx , and examination using a fiberoptic laryngoscope revealed diffuse mucosal swelling and erosion extending from the oral cavity to the epiglottis , which obstructed the view of the vocal cords ( fig .
endotracheal intubation was performed because his respiratory status was predicted to deteriorate , although he was well oxygenated and ventilated at that time .
after admission to the intensive care unit , the upper gastrointestinal tract was examined using a flexible endoscope , and mucosal hyperemia , swelling , hemorrhage , and some necrotic changes extending from the oral cavity to the pharynx and epiglottis were observed .
supportive therapy was maintained , including intravenous steroid administration to reduce airway swelling , and he was examined regularly to evaluate the airway status and assess the feasibility of extubation .
early tracheostomy was considered , but it was not performed in the first week after admission because he refused the procedure ; therefore , we decided to wait for spontaneous recovery .
however , on day 12 of hospitalization , fiberoptic examination and computed tomography of the neck revealed persistent stenosis of the supraglottic and subglottic areas ( fig .
therefore , tracheostomy was performed on day 14 of admission , and remnant mucosal damage was still present ( fig .
the tracheostomy tube was successfully removed after confirming recovery , and the stoma was closed on day 21 of hospitalization .
he visited the outpatient clinic for follow - up 1 month after discharge , and no functional or structural sequelae were noted .
sp / mc powder , composed of sodium picosulfate , magnesium oxide , and citric acid , is widely prescribed for bowel preparation .
when the powder is dissolved in water , magnesium oxide and citric acid react to form magnesium citrate . in solution ,
sodium picosulfate acts as a laxative resulting in augmented peristalsis , and magnesium citrate acts as an osmotic laxative and is not absorbed in the gastrointestinal tract .
side effects of sp / mc are uncommon ; however , it has been reported to induce nausea , vomiting , abdominal pain , dehydration , and electrolyte disturbances .
the most serious known adverse effect is severe electrolyte imbalance that includes hyponatremia , and rapid worsening of hyponatremia can lead to death . to our knowledge
, this is the first report of life - threatening upper airway mucosal damage induced by direct ingestion of sp / mc powder .
reported esophageal and gastric mucosal ulcers that resulted from the inadvertent ingestion of sp / mc powder .
however , it may be related to direct thermal injury from heat generated when the powder mixes with a small volume of water or secretions .
citric acid may also cause caustic injury to the mucosa . considering that sp / mc powder is commonly used for bowel cleansing , ed physicians and those who prescribe sp / mc powder should be aware that serious mucosal injury can occur if the powder is directly ingested without dissolving it in water
in particular , health care providers should emphasize that sp / mc powder should be dissolved in an adequate volume of water .
a 59-year - old man presented to the emergency department with a chief complaint of sore throat after swallowing sodium picosulfate / magnesium citrate powder for bowel preparation , without first dissolving it in water . 
 the initial evaluation showed significant mucosal injury involving the oral cavity , pharynx , and epiglottis . 
 endotracheal intubation was performed for airway protection in the emergency department , because the mucosal swelling resulted in upper airway compromise . 
 after conservative treatment in the intensive care unit , he underwent tracheostomy because stenosis of the supraglottic and subglottic areas was not relieved . 
 the tracheostomy tube was successfully removed after confirming recovery , and he was discharged 3 weeks after admission .