Non-dihydropyridine Calcium Channel Blockers

Non-dihydropyridine calcium channel blockers (non-DHP CCBs) are used in the treatment of hypertension, angina, and atrial fibrillation. Non-DHP CCBs have more of a negative inotropic and chronotropic effect than DHP CCBs, which is the reason for the drugs usefulness in atrial fibrillation as a rate controlling agent.  Non-DHPs have less vasodilatory effects than DHPs and do not cause as much of an effect on blood pressure. AV blockade, peripheral edema are side effects.  Due to negative inotropic effects, care should be taken in patients with heart failure.

Class Drugs

• Diltiazem

• Verapamil

Class Mechanism of Action

Binds to and blocks L-type calcium channels

• Decreases inward movement of calcium in heart and smooth muscle cell of coronary and peripheral arterioles

• Results in relaxation of arteriolar smooth muscle cells

• Some preference for calcium channels in the SA and AV nodes

Class Applications

Hypertension

• Negative inotropy (decreased contractility of cardiac muscle)

• Arteriolar dilatation

Effort-Induced Angina

• Reduces myocardial oxygen consumption

Decreases contraction of cardiac muscle cells

• Decreases peripheral vascular resistance

Vasospastic Angina

• Decreases vasospasm, by relaxing coronary arteries

Atrial Fibrillation

• Decreased AV nodal conduction

Class Adverse Effects

• AV Block

• Dizziness

• Flushing

• Headache

• Peripheral edema

• Avoid in heart failure

Negative inotropic effects

Drug Table

Drug Name	Application	Comments	Image
Diltiazem			"Dill Pickle" "Ties"
Verapamil			"Wrap" "Million"