amlodipine besylate

Norvasc

Pharmacologic class: Calcium channel blocker

Therapeutic class: Antihypertensive

Pregnancy risk category C

Action

Inhibits influx of extracellular calcium ions, thereby decreasing myocardial contractility, relaxing coronary and vascular muscles, and decreasing peripheral resistance

Availability

Tablets: 2.5 mg, 5 mg, 10 mg

Indications and dosages

➣ Essential hypertension, chronic stable angina pectoris, and vasospastic angina (Prinzmetal's angina)

Adults: 5 to 10 mg P.O. once daily

Dosage adjustment

• Hepatic impairment

• Elderly patients

Off-label uses

• Pulmonary hypertension

• Raynaud's disease

Contraindications

• Hypersensitivity to drug

Precautions

Use cautiously in:

• aortic stenosis, severe hepatic impairment, heart failure

• elderly patients

• pregnant or breastfeeding patients

• children.

Administration

• Be aware that this drug may be given alone or with other drugs to relieve hypertension or angina.

Adverse reactions

CNS: headache, dizziness, drowsiness, light-headedness, fatigue, weakness, lethargy

CV: peripheral edema, angina, bradycardia, hypotension, palpitations

GI: nausea, abdominal discomfort

Musculoskeletal: muscle cramps, muscle pain or inflammation

Respiratory: shortness of breath, dyspnea, wheezing

Skin: rash, pruritus, urticaria, flushing

Interactions

Drug-drug. Beta-adrenergic blockers: increased risk of adverse effects

Fentanyl, nitrates, other antihypertensives, quinidine: additive hypotension

Drug-behaviors. Acute alcohol ingestion: additive hypotension

Patient monitoring

See Monitor patient for worsening angina.

• Monitor heart rate and rhythm and blood pressure, especially at start of therapy.

See Assess for heart failure; report signs and symptoms (peripheral edema, dyspnea) to prescriber promptly.

See Give sublingual nitroglycerin, as prescribed, if patient has signs or symptoms of acute myocardial infarction (especially when dosage is increased).

Patient teaching

• If patient also uses sublingual nitroglycerin, tell him he can take nitroglycerin as needed for acute angina.

• Caution patient to avoid driving and other hazardous activities until he knows how drug affects concentration and alertness.

• As appropriate, review all other significant adverse reactions, especially those related to the drugs and behaviors mentioned above.