Is Cardizem (diltiazem) used to treat hypertension?

Cardizem (Diltiazem) as an Antihypertensive Medication

Yes, Cardizem (diltiazem) is definitely a blood pressure medication that is used to treat hypertension, though it has multiple cardiovascular indications.

Mechanism and Classification

Diltiazem is a non-dihydropyridine calcium channel blocker (CCB) that works by:

• Inhibiting calcium influx during membrane depolarization of cardiac and vascular smooth muscle 1
• Causing vasodilation, which reduces peripheral vascular resistance and lowers blood pressure 1
• Decreasing myocardial oxygen demand through reductions in heart rate and systemic blood pressure 1

FDA-Approved Indications

Diltiazem (Cardizem) is FDA-approved for:

1. Hypertension - Used as an antihypertensive medication 2, 1
2. Angina pectoris (both stable angina and coronary artery spasm) 1
3. Certain cardiac arrhythmias

Dosing for Hypertension

• Starting dose: 240mg daily as extended-release formulation 3
• Maintenance dose range: 120-360mg once daily 3
• Maximum recommended dose: 360mg daily 3

Interestingly, research indicates that diltiazem is often underdosed for hypertension, with studies showing a linear dose-response relationship through the 480-540 mg/day range 4.

Place in Hypertension Treatment

According to guidelines:

• Diltiazem is listed in the JNC 7 and ACC/AHA guidelines as an effective antihypertensive medication 2
• It can be used as monotherapy or in combination with other antihypertensive agents 2
• It may be particularly useful in patients with:
  • Stable angina who also have hypertension 2
  • Patients with continuing or frequently recurring ischemia when β-blockers are contraindicated 2

Important Contraindications and Cautions

Diltiazem should be avoided in:

• Patients with heart failure with reduced ejection fraction (HFrEF) 2, 3
• Patients with left ventricular dysfunction (LVEF <40%) 3, 1
• Patients with AV block greater than first degree 3, 1
• Patients with sick sinus syndrome 1

Drug Interactions

• Avoid routine combination with beta-blockers due to increased risk of bradycardia and heart block 2, 3
• Use caution with other medications that affect cardiac conduction 1

Monitoring

When using diltiazem for hypertension, monitor:

• Blood pressure response
• Heart rate and cardiac conduction
• Signs of fluid retention (edema)
• Symptoms of hypotension or bradycardia 3

Comparative Efficacy

Studies have shown that the antihypertensive effect of diltiazem is similar to that of other antihypertensive therapies including diuretics, beta-blockers, ACE inhibitors, and other calcium channel blockers 5.

Unlike some other antihypertensive medications, diltiazem does not adversely affect electrolytes or carbohydrate/lipid metabolism, which may be advantageous in certain patient populations 5.

In summary, Cardizem (diltiazem) is indeed a blood pressure medication with established efficacy in treating hypertension, though it has additional cardiovascular indications and important contraindications that must be considered when selecting it for treatment.