Calcium channel blockers are effective in treating hypertension because they reduce peripheral resistance.

Arteriolar vascular tone depends on free intracellular Ca²⁺ concentration. Calcium channel blockers reduce transmembrane movement of Ca²⁺ , reduce the amount reaching intracellular sites and therefore reduce vascular smooth muscle tone.

All calcium channel blocks appear similarly effective for management of mild to moderate hypotension.

For low-renin hypertensive patients (elderly and African-American groups), Ca²⁺ channel blockers appear good choices for monotherapy (single drug) control.

Nisoldipine, a dihydropyridine, is similar to nifedipine but five to ten times more potent as a vasodilator and little effect on myocardial contractility.

Nisoldipine is available as a long-acting extended release preparation and appears effective in treating mild to moderate hypertension.

Adverse Effects:

• Dizziness, headache and peripheral edema.

• Concurrent use of cimetadine, a fatty meal, or grapefruit juice may increase serum concentations and increase toxicity.