When should administration of Cardizem (diltiazem) be held?

From the Guidelines

Cardizem (diltiazem) administration should be held in patients with wide-complex tachycardias, impaired ventricular function, or heart failure, as well as in cases of pre-excited atrial fibrillation or flutter, due to the risk of accelerating the ventricular response or worsening cardiac function 1. When considering the administration of Cardizem, it is crucial to assess the patient's cardiac status and the specific type of arrhythmia they are experiencing.

• Key factors to consider when deciding whether to hold Cardizem administration include:
  • The presence of wide-complex tachycardias, which may be exacerbated by the drug
  • Impaired ventricular function or heart failure, as diltiazem can further reduce cardiac output
  • Pre-excited atrial fibrillation or flutter, where AV nodal blocking agents like diltiazem may accelerate the ventricular response
  • The patient's heart rate and blood pressure, as diltiazem can cause bradycardia and hypotension
• According to the 2010 American Heart Association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care 1, caution is advised when using AV nodal blocking agents like diltiazem in certain situations, and the drug should be used with caution in patients with obstructive pulmonary disease or congestive heart failure.
• The guidelines also recommend specific dosing regimens for diltiazem, including an initial dose of 15 mg to 20 mg (0.25 mg/kg) IV over 2 minutes, with potential additional doses and a maintenance infusion dose of 5 mg/hour to 15 mg/hour, titrated to heart rate 1.
• It is essential to carefully evaluate the patient's response to diltiazem and adjust the treatment plan as needed to minimize the risk of adverse effects and ensure optimal outcomes.

From the FDA Drug Label

The drug should be used with caution in patients with impaired renal or hepatic function Should a dermatologic reaction persist, the drug should be discontinued.

The administration of Cardizem (diltiazem) should be held in the following situations:

• Impaired renal or hepatic function: The drug should be used with caution in these patients.
• Dermatologic reactions: If a dermatologic reaction persists, the drug should be discontinued.
• Concomitant use with certain medications: Such as beta-blockers, digitalis, or statins, which may require dose adjustments or careful monitoring.

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From the Research

Administration of Cardizem (Diltiazem)

The administration of Cardizem (diltiazem) should be held in certain situations, including:

• Patients with severe left ventricular dysfunction, as treatment with diltiazem can result in abrupt decompensation and development of overt pulmonary edema and hypotension 3
• Patients with congestive heart failure who are not closely monitored, as diltiazem can cause a deterioration in cardiac function due to its negative inotropic actions 3
• Patients who have ingested a massive overdose of diltiazem, as this can lead to severe hypotension, bradycardia, and heart block 4, 5
• Patients with atrial fibrillation and concomitant heart failure should be treated with caution, as diltiazem is not recommended due to negative inotropic effects, although some studies suggest similar safety and effectiveness outcomes compared to metoprolol 6

Key Considerations

• Diltiazem's relative lack of negative inotropic effects may allow it to be used safely in patients with congestive heart failure, particularly when control of supraventricular tachyarrhythmia is required 3
• Intravenous and short-term oral diltiazem can improve left ventricular performance and reduce myocardial oxygen demand in severe congestive heart failure 7
• Patients with heart failure with reduced ejection fraction (HFrEF) or heart failure with preserved ejection fraction (HFpEF) should be closely monitored when treated with diltiazem 6

Potential Risks

• Diltiazem can cause transient junctional arrhythmias, hypotension, and reduced cardiac function 7, 5
• Massive overdose of diltiazem can lead to severe hypotension, bradycardia, and heart block 4, 5
• Diltiazem may not be beneficial in patients with severe left ventricular dysfunction, and alternative treatments should be considered 3