Complex ADHD Challenging Case: Managing Co-Occurring Attention-Deficit Hyperactivity Disorder and Congenital Heart Disease with a Limited Medication Formulary: A Case from Mexico.

DL is an 8-year-old Mexican boy with a posterior atrial septal defect and partial anomalous pulmonary venous return of the right lower pulmonary vein with resultant right heart dilation with normal right ventricular systolic and diastolic function and no arrhythmias. Surgical repair was deferred, and DL's condition was being medically managed with furosemide 0.5 mg/kg BID and spironolactone 0.5 mg/kg BID.DL presents for developmental assessment due to poor performance in school following a lifting of COVID-19 pandemic restrictions and return to in-person classes. He has been attending full-time classes for 3 months without improvements in math, reading, and writing skills. Current attentional concerns at school include an inability to complete tasks without getting distracted by minimal stimuli and highly impulsive behavior.At the first assessment, DL was performing below grade expectations (e.g., reading by syllable without text comprehension, demonstrating preoperational addition and subtraction skills, inability to take dictation)-all of which was viewed as negatively impacted by attentional deficits. DL met DSM-5 criteria for ADHD, predominantly inattentive type. He was started on 10-mg immediate-release methylphenidate PO at 8 am with breakfast and a second dose of 10-mg immediate-release methylphenidate PO 4 hours after the first dose.After a month, at the first follow-up consultation, improvement in attention span, impulsivity, and school performance were observed, including reading skills and math proficiency. However, DL's mother raised concerns about circumoral cyanosis and acrocyanosis in the fingers of both hands after playing outside. These signs were not previously observed. During physical examination at the same visit, heart rate, blood pressure, and oximetry were within baseline ranges and his cardiac examination was unchanged. DL's dosage of methylphenidate was lowered to 10-mg immediate-release methylphenidate PO QD in the mornings with breakfast (8 am).DL did not return to clinic for another 2 months, having discontinued the medication after 2 months of treatment given financial limitations. His mother reported that DL's exertional circumoral cyanosis and acrocyanosis resolved while he was off medication. However, she observed an increase in inattentive symptoms and impulsivity and decline in his academic skills. She asked if our team was able continue the treatment despite the drug side effects, since she believed the benefits outweighed the disadvantages.Given these concerns, the team requested an updated cardiology assessment. The Cardiologist recommended discontinuation of methylphenidate and recommended follow-up with cardiothoracic surgery for reassessment of the surgical timeline.Given the limited treatment options in Mexico, what would you do next as the treating developmental-behavioral clinician…?