Does Cardizem (Diltiazem) cause hypotension?

From the Guidelines

Yes, Cardizem (Diltiazem) can cause hypotension, as it is listed as a potential side effect in the properties of calcium channel blockers table. According to the study published in the Journal of the American College of Cardiology 1, the properties of calcium channel blockers, including Diltiazem, are outlined in a table that lists hypotension as a potential side effect.

Mechanism of Action

Diltiazem works by relaxing blood vessels, allowing blood to flow more easily and reducing the workload on the heart. This medication blocks calcium from entering the cells of the heart and blood vessels, which causes the vessels to dilate and reduces peripheral resistance.

Dosage and Administration

The usual dose of Diltiazem is listed as 30 to 90 mg 4 times daily for immediate release, and 120 to 360 mg once daily for slow release formulations 1. Patients should take Cardizem consistently, either with or without food, but should maintain the same pattern.

Side Effects and Interactions

Side effects may include hypotension, dizziness, flushing, bradycardia, and edema 1. It's essential to monitor blood pressure when starting or adjusting the dose of this medication, especially when combined with other medications like beta-blockers. Patients should inform their doctor about all medications they are taking to avoid potential interactions.

Clinical Considerations

In clinical practice, it is crucial to weigh the benefits of using Diltiazem against the potential risks, including hypotension, especially in patients with certain comorbidities or those taking other medications that may exacerbate this effect. The study suggests that heart rate-slowing CCBs like Diltiazem can be administered early to patients with UA/NSTEMI without HF without overall harm and with trends toward a benefit 1. However, greater caution is indicated when combining a beta blocker and CCB for refractory ischemic symptoms, as they may act in synergy to depress LV function and sinus and AV node conduction.

From the FDA Drug Label

1. Hypotension: Decreases in blood pressure associated with diltiazem hydrochloride therapy may occasionally result in symptomatic hypotension. Events observed following diltiazem overdose included bradycardia, hypotension, heart block, and cardiac failure. Hypotension: Vasopressors (e.g., dopamine or norepinephrine).

Yes, Cardizem (Diltiazem) can cause hypotension. Decreases in blood pressure associated with diltiazem hydrochloride therapy may occasionally result in symptomatic hypotension, and hypotension has been observed in cases of diltiazem overdose 22.

From the Research

Cardizem (Diltiazem) and Hypotension

• Diltiazem has been reported to cause hypotension as one of its adverse effects 3.
• The risk of hypotension may be increased when diltiazem is combined with beta-blockers, especially in patients with left ventricular dysfunction or latent cardiac conduction deficits 4.
• A study reported two cases of cardiogenic shock with severe bradycardia in patients taking a combination of slow-release diltiazem and a beta-blocker for hypertension 5.
• However, in a study examining the safety and efficacy of an extended-release form of diltiazem HCl in patients with mild-to-moderate essential hypertension, no significant differences were noted in adverse events, including hypotension, between the diltiazem XR and placebo groups 6.
• The most common adverse events during diltiazem therapy include headache, flushing, peripheral oedema, and hypotension, with atrioventricular block being the most frequent serious adverse event related to diltiazem therapy 3.

Combination Therapy and Hypotension

• Combination therapy with diltiazem and a beta-blocker may enhance therapeutic benefit in patients with hypertension or coronary heart disease, but it may also increase the risk of adverse effects, including hypotension 4.
• Patients on combination therapy with diltiazem and a beta-blocker should have their blood pressure, heart rate, and atrioventricular conduction on ECG monitored regularly to minimize the risk of hypotension and other adverse effects 4.

Patient Populations and Hypotension

• Diltiazem appears to be an effective and well-tolerated treatment for hypertension and angina in older patients, but it may cause hypotension in some cases 3.
• The antihypertensive efficacy of diltiazem has been studied in various demographic groups, and it has been shown to be similar to that of other therapies, including diuretics, beta-blockers, and angiotensin-converting enzyme inhibitors 7.