Verapamil Toxicity

Abstract

Verapamil blocks the rapid influx of calcium into the cardiac myocytes of the cardiac conduction system and smooth muscle of the vasculature, resulting in decreased myocardial contractility, prolonged conduction time, and vascular relaxation. A sustained-release form, verapamil SR (or ER), is available that contains higher levels of medication and requires only once-daily dosing. The majority of reported fatal cases of verapamil toxicity are due to massive, intentional overdoses. Herein, we present an unusual case of fatal verapamil SR toxicity in a 57-year-old female that resulted from accidental overdose of only 3 tablets (720 mg), as witnessed by the decedent's daughter. In spite of the low dose ingested, the postmortem cardiac blood verapamil level was clearly toxic (6000 ng/mL, or 6 mg/L). Her preexisting medical conditions included hypercholesterolemia, hypertension, iron deficiency anemia, diabetes mellitus, and associated mild chronic renal failure. Complicating factors, which likely include the decedent's preexisting renal and cardiac disease, and a review of the available literature will be discussed.

Verapamil Improves the Activity of Bedaquiline against Mycobacterium abscessusIn Vitro and in Macrophages

“…1B, upper panel). In the context of well documented toxicity of VER (17,18), the maximal range of systemic verapamil concentrations that have been achieved in the clinic by rapid continuous intravenous An exponential-phase culture of M. abscessus CIP104536 T (smooth variant) was serially 10-fold diluted, and 5-l volumes of each dilution were spotted onto the agar plates, which were then incubated at 37°C for 4 days before pictures were taken. (B) Line graph showing a hyperbolic decrease in BDQ MIC as the VER concentration is increased (top panel).…”

Cardiotoxicity of verapamil in renal failure: a case report and review of the literature

“…Earlier reports have suggested that slow release verapamil can cause acute toxic effects (slow cardiac rhythms and hypotension) in patients with chronic renal failure [2,3]. Death with 720 mg sustained release verapamil has also been reported [4]. Though our patient was on therapeutic doses, she was taking a dose in the higher range of the recommended.…”

Severe Cardiac and Renal Findings in an Adolescent Girl: Trandolapril/Verapamil Hydrochloride Overdose

“…Tarka® is an antihypertensive drug that is approved by US Food and Drug Administration and contains combination of verapamil SR and trandolapril (4) . Verapamil is a calcium channel blocker (CCB).…”

“…A significant part, and metabolites of verapamil (70%) are excreted through kidneys. Due to the wide usage area of verapamil and verapamil SR, numerous intoxication cases are reported in the literature (4) . Trandolapril is an angiotensin-converting enzyme inhibitor (ACE-I) and it reduces the angiotensin II level which is a potent vasoconstructor and decreases systemic blood pressure (6) .…”

“…Batalis et al (16) reported a case who was found in an unconscious state 12 hours after taking Tarka and died within a short period of time. Cohen et al (11) reported a 60-year-old male patient admitted with complaint of dizziness after taking 5 tablets of Tarka and he had been found in a hypotensive and bradycardic state 8 hours later.…”