Background: Lisinopril is an angiotensin converting enzyme inhibitor used for treatment of hypertension, congestive heart failure, and acute myocardial infarction. Reports of clinical experience with pediatric ingestions are minimal.
Method: A 13-year retrospective study of lisinopril ingestions in children reported to the California Poison Control System was analyzed and case notes were reviewed. Institutional Review Board approval was obtained and cases were blinded. Inclusion criteria were lisinopril as a single ingestant, age less than 6 years, treatment in a health care facility, case followed to a known outcome.
Results: Inclusion criteria were met in 296 cases. Demographics include 51% of male patients and the mean age was 1.97 years (range: 9 months-5 years). Of the 296 patients, 8 patients (2.7%) developed hypotension (ranges: 55-74 mm Hg systolic and 22-48 mm Hg diastolic). The lowest blood pressure of 55/22 mm Hg was recorded in a 22-month old male who ingested an estimated 120-mg lisinopril (13.3 mg/kg). The lowest dose of lisinopril causing hypotension was with an estimated dose of approximately 50 mg or 3.9 mg/kg in a 2-year old. Two hundred and eighty-two patients (95.3%) were treated and released from the emergency department and 14 patients (4.7%) were admitted. The dose ingested was reported in 189 cases and an exact-dose of lisinopril was reported in 61 patients (20.6%); mean amount ingested was 3.0 mg/kg, median amount ingested was 2.1 mg/kg (range: 0.1-10.9 mg/kg, N = 38); and mean total dose was 33.4 mg, median total dose was 20 mg (range: 2.5-160 mg, N = 61). None of the patients with exact-dose lisinopril ingestions developed hypotension, received intravenous fluids, or were admitted.
Conclusion: The lowest estimated dose of lisinopril to cause hypotension was 50 mg or 3.9 mg/kg. Although continued evaluation of pediatric lisinopril ingestions is essential to determine more specific thresholds of toxicity, the lack of effect on blood pressure in children with exact-dose ingestions indicate that pediatric lisinopril ingestions (for ages > 9 months) ≤ 4 mg/kg up to 40 mg total may be safely managed at home.