Home Drug Guide Carvedilol

Drug Guide

Generic Name

Carvedilol

Brand Names Coreg

Classification

Therapeutic: Antihypertensive, Heart failure agent

Pharmacological: Non-selective beta-adrenergic blocker with alpha-1 blocking activity

FDA Approved Indications

Hypertension
Heart failure with reduced ejection fraction
Left ventricular dysfunction after myocardial infarction

Mechanism of Action

Carvedilol blocks both beta-adrenergic receptors and alpha-1 adrenergic receptors, leading to decreased heart rate, myocardial contractility, and vasodilation, which collectively lower blood pressure and reduce cardiac workload.

Dosage and Administration

Adult: Typically start with 6.25 mg twice daily, titrate based on response and tolerability. Maintenance doses range from 12.5 to 25 mg twice daily.

Pediatric: Safety and efficacy not established; use in children is not routinely recommended.

Geriatric: Initiate at lower doses due to increased sensitivity and potential for side effects.

Renal Impairment: May require dosage adjustment; monitor renal function regularly.

Hepatic Impairment: Start at lower doses; monitor liver function as needed.

Pharmacokinetics

Absorption: Well absorbed orally, with extensive first-pass metabolism.

Distribution: Widely distributed in tissues; highly bound to plasma proteins.

Metabolism: Primarily metabolized in the liver via CYP2D6 and CYP3A4 enzymes.

Excretion: Excreted mainly via feces; small amounts in urine.

Half Life: Approximately 7 to 10 hours, allowing for twice-daily dosing.

Contraindications

Asthma or bronchospastic disease
Salty or sinus bradycardia
Heart block greater than first degree without pacemaker
Sick sinus syndrome

Precautions

Use with caution in diabetes mellitus (may mask hypoglycemia symptoms), peripheral vascular disease, and hepatic impairment. Monitor for signs of heart failure.

Adverse Reactions - Common

Dizziness (Common)
Fatigue (Common)
Hypotension (Common)
Weight gain (Less common)

Adverse Reactions - Serious

Bradycardia (Uncommon)
Heart failure worsening (Uncommon)
Bronchospasm (Rare)
Liver enzyme elevation (Rare)

Drug-Drug Interactions

Other antihypertensives, especially calcium channel blockers like verapamil or diltiazem
Insulin and oral hypoglycemics (may enhance hypoglycemia)
Clonidine

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor blood pressure, heart rate, signs of heart failure, and blood glucose levels as appropriate.

Diagnoses:

Ineffective tissue perfusion
Risk for falls due to dizziness
Impaired cardiac output

Implementation: Administer with food to minimize orthostatic hypotension. Titrate doses gradually. Educate patients on daily blood pressure and heart rate monitoring.

Evaluation: Assess therapeutic response and side effects; adjust dose accordingly.

Patient/Family Teaching

Do not discontinue abruptly to avoid rebound hypertension.
Take medication with food to reduce orthostatic hypotension.
Report signs of dizziness, shortness of breath, or worsening heart failure.
Monitor blood pressure regularly.

Special Considerations

Black Box Warnings:

None specific to carvedilol, but caution with heart failure and in diabetic patients due to masking hypoglycemia symptoms.

Genetic Factors: Variable metabolism via CYP2D6; poor metabolizers may have increased drug levels.

Lab Test Interference: May alter liver function tests.

Overdose Management

Signs/Symptoms: Severe hypotension, bradycardia, heart failure, bronchospasm.

Treatment: Supportive care, including IV fluids for hypotension, atropine for bradycardia, and vasopressors if needed. Do not induce vomiting.

Storage and Handling

Storage: Store at room temperature, away from moisture and light.

Stability: Stable until expiration date on packaging.