P3160 - Unexpected Consequences of ADHD Medications: A Case of Lisdexamfetamine-Induced Paralytic Ileus

Dagoberto Morales, MD¹, Andy Sam, DO¹, Guillermo Loyola, BSc², Eric Gutierrez, BSc², William A.. Perez, MD^1
1Palmetto General Hospital, Hialeah, FL; ²Nova Southern University, Miami, FL

Introduction: Lisdexamfetamine, a prodrug of dextroamphetamine, is commonly used in the treatment of attention-deficit/hyperactivity disorder (ADHD)[1]. In this case report, we describe a 55-year-old male with a history of ADHD who developed a medication-induced paralytic ileus secondary to lisdexamfetamine.

Case Description/Methods: A 55-year-old male with a past medical history of ADHD presented to the ED complaining of diffuse abdominal pain, nausea, and vomiting. The patient denied any previous episodes of similar symptoms, he also denied hernias, trauma, or past surgeries. Initially, a CT scan of the abdomen and pelvis showed signs suggestive of a small bowel obstruction (Figure 1). The patient was then treated appropriately for small bowel obstruction. On the second day of admission, a KUB was indicative of a small bowel ileus (Figure 1) and the patient’s Lisdexamfetamine was discontinued.

The patient admitted to improved abdominal pain and symptoms on the second day of admission. Repeat KUB on the third and fourth day of admission demonstrated a significant decrease in dilatation and air through several dilated loops of small bowel, indicative of improving small bowel ileus (Figure 1). After discontinuing lisdexamfetamine, the patient's condition rapidly improved. There were no signs of inflammation, neurological disorders, or hormonal and electrolyte imbalances. Thus, we concluded that the patient had a medication-induced paralytic ileus due to lisdexamfetamine. The patient was discharged and underwent a normal colonoscopy. He was advised to stop taking the medication and consult his primary care physician for an alternative treatment.

Discussion: Lisdexamfetamine, a prodrug of dextroamphetamine, affects the central nervous system by increasing dopamine and norepinephrine release. It also has peripheral effects on the gastrointestinal system. The exact mechanism of paralytic ileus in this case is not fully understood, but possible factors include direct stimulation of α2-adrenergic receptors and activation of D2 receptors by released norepinephrine and dopamine, respectively. This case emphasizes the need to consider medication-induced complications when patients on medications like lisdexamfetamine present with abdominal symptoms. [1]

References:
[1] Najib J. The efficacy and safety profile of lisdexamfetamine dimesylate, a prodrug of d-amphetamine, for the treatment of attention-deficit/hyperactivity disorder in children and adults. Clin Ther. 2009 Jan;31(1):142-76.



Disclosures:


Dagoberto Morales, MD¹, Andy Sam, DO¹, Guillermo Loyola, BSc², Eric Gutierrez, BSc², William A.. Perez, MD¹. P3160 - Unexpected Consequences of ADHD Medications: A Case of Lisdexamfetamine-Induced Paralytic Ileus, ACG 2023 Annual Scientific Meeting Abstracts. Vancouver, BC, Canada: American College of Gastroenterology.