Nifedipine overdose

Overdosage topics
Overview 4800 mg ingestion 900 mg ingestion 280 mg ingestion

Overview
Experience with Nifedipine overdosage is limited. Generally, overdosage with Nifedipine leading to pronounced hypotension calls for active cardiovascular support including monitoring of cardiovascular and respiratory function, elevation of extremities, judicious use of calcium infusion, pressor agents and fluids. Clearance of Nifedipine would be expected to be prolonged in patients with impaired liver function. Since Nifedipine is highly protein-bound, dialysis is not likely to be of any benefit. Return to top

4800 mg ingestion
There has been one reported case of massive overdosage with Nifedipine extended-release tablets. The main effects of ingestion of approximately 4800 mg of Nifedipine extended-release in a young man attempting suicide as a result of cocaine-induced depression was initial dizziness, palpitations, flushing, and nervousness. Within several hours of ingestion, nausea, vomiting, and generalized edema developed. No significant hypotension was apparent at presentation, 18 hours post-ingestion. Electrolyte abnormalities consisted of a mild, transient elevation of serum creatinine, and modest elevations of LDH and CPK, but normal SGOT. Vital signs remained stable, no electrocardiographic abnormalities were noted and renal function returned to normal within 24 to 48 hours with routine supportive measures alone. No prolonged sequelae were observed. Return to top

900 mg ingestion
The effect of a single 900 mg ingestion of Nifedipine immediate-release capsules in a depressed anginal patient also on tricyclic antidepressants was loss of consciousness within 30 minutes of ingestion, and profound hypotension, which responded to calcium infusion, pressor agents, and fluid replacement. A variety of ECG abnormalities were seen in this patient with a history of bundle branch block, including sinus bradycardia and varying degrees of AV block. These dictated the prophylactic placement of a temporary ventricular pacemaker, but otherwise resolved spontaneously. Significant hyperglycemia was seen initially in this patient, but plasma glucose levels rapidly normalized without further treatment. Return to top

280 mg ingestion
A young hypertensive patient with advanced renal failure ingested 280 mg of Nifedipine immediate-release capsules at one time, with resulting marked hypotension responding to calcium infusion and fluids. No AV conduction abnormalities, arrhythmias, or pronounced changes in heart rate were noted, nor was there any further deterioration in renal function. Return to top