Pregnancy Risk Category C
How supplied
Tablets: 20 mg, 40 mg, 80 mg, 120 mg, 160 mg
Action
A beta blocker that reduces cardiac oxygen demand by blocking catecholamine-induced increases in heart rate, blood pressure, and force of myocardial contraction. Depresses renin secretion.
Indications & dosage
Angina pectoris--
Adults: 40 mg P.O. once daily. Dosage increased in 40- to 80-mg increments at 3- to 7-day intervals until optimum response occurs. Usual maintenance dose is 40 to 80 mg once daily; up to 240 mg once daily may be needed.
Hypertension--
Adults: 20 to 40 mg P.O. once daily. Dosage increased in 40- to 80-mg increments until optimum response occurs. Usual maintenance dose is 40 to 80 mg once daily. Doses of 320 mg may be needed.
Adjust-a-dose: For patients with renal failure, dosage interval should be adjusted based on creatinine clearance. For creatinine clearance of over 50 ml/minute, give dose q 24 hours; for clearance of 31 to 50 ml/minute, give dose q 24 to 36 hours; for clearance of 10 to 30 ml/minute, give dose q 24 to 48 hours; and for clearance below 10 ml/minute, give dose q 40 to 60 hours.
Adverse reactions
CNS: fatigue, dizziness.
CV: bradycardia, hypotension, heart failure, peripheral vascular disease, rhythm and conduction disturbances.
GI: nausea, vomiting, diarrhea, abdominal pain, constipation, anorexia.
Respiratory: increased airway resistance.
Skin: rash.
Other: fever.
Interactions
Drug-drug. Antihypertensives: enhanced antihypertensive effect. Monitor closely.
Cardiac glycosides: excessive bradycardia and additive effects on AV conduction. Use together cautiously.
Epinephrine: severe vasoconstriction and reflex bradycardia. Monitor blood pressure carefully.
Insulin, oral antidiabetics: can alter dosage requirements in previously stabilized diabetic patients. Observe patient carefully.
Phenothiazines: can result in additive hypotensive effects. Monitor closely.
NSAIDs: decreased antihypertensive effect. Monitor blood pressure and adjust dosage.
Effects on diagnostic tests
None reported.
Contraindications
Contraindicated in patients with bronchial asthma, sinus bradycardia and greater than first-degree heart block, and cardiogenic shock.
Nursing considerations
Patient teaching
*Liquid contains alcohol. **May contain tartrazine. †Canada ‡Australia §U.K. OTCOver the counter
Reactions may be common, uncommon, life-threatening, or COMMON AND LIFE-THREATENING