Carvedilol
Brand Names: Coreg & Coreg CR
Generic Available
Common Dosage Forms:
Tablets: 3.125 mg, 6.25 mg, 12.5 mg, 25 mg.
Capsules (Coreg CR): 10 mg, 10 mg, 20 mg, 40 mg, and 80 mg.
FDA Indications/Dosages:
For the management of essential hypertension when used alone or in combination with other antihypertensive agents, especially thiazide-type diuretics: Start with 6.25 mg given twice a day. After 7-14 days and using standing systolic pressure one hour after dosing as a guide, increase dosage to 12.5 mg twice a day. Further dosage increases to 25 mg twice a day and may be made after another 7-14 days.
For the treatment of mild to moderate heart failure of ischemic or cardiomyopathic origin, in combination with digitalis, diuretics, and an ACE inhibitor, to reduce the progression of disease: Start with 3.125 mg given twice a day for 14 days. Dose may be doubled every 14 days to the highest level tolerated by the patients. The maximum dose is 25 mg twice a day in patients weighing less than 85 kg and 50 mg twice a day in patients weighing more than 85 kg. Take with food to slow the rate of absorption and decrease orthostatic effects.
For the use in patients with left ventricular dysfunction (LVEF of ≤ 40%) following myocardial infarction: Start treatment after the patient is hemodynamically stable and fluid retention has been minimized. Start with 6.25 mg given twice a day. Increase the dose after 3-10 days to 12.5 mg twice a day and again after 3-10 days to the target dose of 25 mg twice daily. A lower starting dose may be used in patients with low blood pressure or heart rate, or mild fluid retention.
Monitor: BP, LFT, BG.
Pharmacology/Pharmacokinetics: Carvedilol is a nonselective beta-adrenergic blocking agent with alpha-1-adrenergic blocking activity. The mechanism of action of carvedilol in the treatment of hypertension may be due to beta-adrenergic blockage resulting in (1) a reduction in cardiac output, (2) a reduction in exercise- and/or isoproterenol-induced tachycardia and (3) reduces reflex orthostatic tachycardia. In congestive heart failure, carvedilol has been shown to reduce systemic blood pressure, pulmonary artery pressure, pulmonary capillary wedge pressure, systemic vascular resistance, and heart rate while increasing stroke volume index. Mean terminal elimination half-life ranges from 7 to 10 hours. 98% is bound to plasma proteins, mainly albumin. Metabolism occurs primarily by aromatic ring oxidation and glucuronidation.
Drug Interactions: Rifampin significantly decreases plasma levels. Cimetidine increases steady-state AUC but not Cmax. Quinidine, fluoxetine, paroxetine, and propafenone may increase plasma levels. Use with reserpine, clonidine, digoxin, or monoamine oxidase inhibitors may produce significant hypotension or bradycardia. Use with diltiazem or verapamil may cause conduction disturbances. May increase digoxin plasma levels. Use with inhibitors of CYP2C9 (amiodarone or fluconazole) may exacerbate bradycardia.
Contraindication/Precautions: Use is contraindicated in patients with NYHA class IV decompensated cardiac failure requiring intravenous inotropic therapy, bronchial asthma or related bronchospastic conditions, second- or third-degree AV block, sick sinus syndrome, cardiogenic shock, or severe bradycardia. Use with caution in patients with hepatic impairment. Discontinue use at the first sign of hepatic dysfunction (e.g., pruritus, dark urine, anorexia, jaundice, right upper quadrant tenderness, or unexplained flu-like symptoms). Use with caution in patients with peripheral vascular disease (can aggravate symptoms), in diabetics (can mask hypoglycemia), and in thyrotoxicosis (can mask hyperthyroidism). Use with caution during anesthesia (due to bradycardia). Pregnancy Category C.
Adverse Effects: Dizziness (32%), diarrhea (12%), bradycardia and hypotension (9%), hyperglycemia (12%), and visual abnormalities (5%) occur in treatment of congestive heart failure. The same effects occur in the treatment of hypertension but at approximately the same rate as seen in placebo.
Patient Consultation:
Store in a cool, dry place away from sunlight and children.
If a dose is missed, take it as soon as possible. If it is closer to the time of your next dose than the dose you missed, skip the missed dose and return to your dosing schedule. Do not double doses.
Take with food to decrease orthostatic hypotension.
Contact a physician if the above side effects are severe or persistent.
Contact lens wearers may experience decreased lacrimation.
Do not discontinue therapy without first consulting physician. Treatment must be tapered over 1 to 2 weeks.
May cause drowsiness. Use caution while operating machinery or when mental alertness is required.
Patients with diabetes need to be aware that this agent can cause masking of hypoglycemic symptoms.
Avoid nonprescription cough, cold, and allergy medications unless otherwise directed.
