Authors: Dr KAM HANG LEONG , Dr HOI IP LEONG , Tam Fei Chang

Abstract

Introduction:

Calcium channel blocker (CCB) overdose typically presents with early hypotension and bradycardia. This case highlights an unusual delayed complication in a 21-year-old female with iron deficiency anemia, depression, and connective tissue disease who intentionally ingested 100 mg of amlodipine.

Case Presentation:

The patient presented 2 hours post-ingestion with dizziness, hypotension (98/57 mmHg), tachycardia (HR 103 bpm), and mild fever (37.7°C). Initial management included IV calcium gluconate and hydration. Unexpectedly, 20 hours later, she developed acute hypoxemia and dyspnea. Imaging revealed bilateral pulmonary infiltrates, pleural effusions, atelectasis, and B-lines on ultrasound, with preserved ejection fraction. NT-proBNP escalated sharply (46 → 1701 → 2002 pg/mL). She was managed with diuretics, steroids, and high-flow nasal cannula (HFNC) oxygen, with suspected non-cardiogenic pulmonary edema.

Key Learning Points:

Atypical Delayed Complication: CCB overdose may precipitate late-onset non-cardiogenic pulmonary edema despite initial hemodynamic stabilization.

Role of Biomarkers & Imaging: Rising NT-proBNP with preserved EF suggests non-cardiac strain; lung ultrasound and CXR are critical for diagnosing pulmonary complications.

Multi-Modal Management: Combination therapy (diuretics + steroids) and advanced respiratory support (HFNC) may be necessary for pulmonary edema refractory to standard CCB overdose protocols.

Risk Factors: Underlying connective tissue disease may potentiate inflammatory lung injury in toxin-mediated insults.

Conclusion:

This case underscores the need for extended monitoring beyond 24 hours in CCB overdose and demonstrates that pulmonary edema, driven by inflammatory mechanisms rather than cardiac failure, can be a delayed life-threatening complication.

Keywords: Calcium channel blocker overdose, Non-cardiogenic pulmonary edema, Bedside ultrasound