Carvedilol
Carvedilol (Coreg)
(kar- VAY-dih-lol)
Carvedilol
Pregnancy Category: C Coreg (Rx)

Classification: Alpha/beta-adrenergic blocking agent

See Also: See also Adrenergic Blocking Agents .

Action/Kinetics: Has both alpha- and beta-adrenergic blocking activity. Decreases cardiac output, reduces exercise- or isoproterenol-induced tachycardia, reduces reflex orthostatic hypotension, causes vasodilation, and reduces peripheral vascular resistance. Significant beta-blocking activity occurs within 60 min while alpha-blocking action is observed within 30 min. BP is lowered more in the standing than in the supine position. Significantly lowers plasma renin activity when given for at least 4 weeks. Rapidly absorbed after PO administration, but there is a significant first-pass effect. Terminal t 1/2: 7-10 hr. Food delays the rate of absorption. Over 98% is bound to plasma protein. Plasma levels average 50% higher in geriatric compared with younger clients. Extensively metabolized in the liver, with metabolites excreted primarily via the bile into the feces.

Uses: Essential hypertension used either alone or in combination with other antihypertensive drugs, especially thiazide diuretics. Used with digitalis, diuretics, and ACE inhibitors to reduce the progression of mild to moderate CHF of ischemic or cardiomyopathic origin. Investigational: Angina pectoris, idiopathic cardiomyopathy.

Contraindications: Clients with New York Heart Association Class IV decompensated cardiac failure, bronchial asthma, or related bronchospastic conditions, second- or third-degree AV block, sick sinus syndrome (unless a permanent pacemaker is in place), cardiogenic shock, severe bradycardia, drug hypersensitivity. Hepatic impairment. Lactation.

Special Concerns: Use with caution in hypertensive clients with CHF controlled with digitalis, diuretics, or an ACE inhibitor. Use with caution in peripheral vascular disease, in surgical procedures using anesthetic agents that depress myocardial function, in diabetics receiving insulin or oral hypoglycemic drugs, in those subject to spontaneous hypoglycemia, or in thyrotoxicosis. Clients with a history of severe anaphylactic reaction to a variety of allergens may be more reactive to repeated challenge while taking beta blockers. Safety and efficacy have not been established in children less than 18 years of age.

Side Effects: CV: Bradycardia, postural hypotension, dependent or peripheral edema, AV block, extrasystoles, hypertension, hypotension, palpitations, peripheral ischemia, syncope, angina, cardiac failure myocardial ischemia, tachycardia, CV disorder. CNS: Dizziness, headache, somnolence, insomnia, ataxia, hypesthesia, paresthesia, vertigo, depression, nervousness, migraine, neuralgia, paresis, amnesia, confusion, sleep disorder, impaired concentration, abnormal thinking, paranoia, emotional lability. Body as a whole: Fatigue, viral infection, rash, allergy, asthenia, malaise, pain, injury, fever, infection, somnolence, sweating, sudden death. GI: Diarrhea, abdominal pain, bilirubinemia, N&V;, flatulence, dry mouth, anorexia, dyspepsia, melena, periodontitis, increased hepatic enzymes, GI hemorrhage. Respiratory: Rhinitis, pharyngitis, sinusitis, bronchitis, dyspnea, asthma, bronchospasm, pulmonary edema, respiratory alkalosis, dyspnea, respiratory disorder, URTI, coughing. GU: UTI, albuminuria, hematuria, frequency of micturition, abnormal renal function, impotence. Dermatologic: Pruritus; erythematous, maculopapular, and psoriaform rashes, photosensitivity reaction, exfoliative dermatitis. Metabolic: Hypertriglyceridemia, hypercholesterolemia, hyperglycemia, hypovolemia, hyperuricemia, increased weight, gout, dehydration, hypervolemia, glycosuria, hyponatremia, hypokalemia, hyperkalemia, diabetes mellitus. Hematologic: Thrombocytopenia, anemia, leukopenia, pancytopenia, purpura, atypical lymphocytes. Musculoskeletal: Back pain, arthralgia, myalgia, arthritis. Otic: Decreased hearing, tinnitus. Miscellaneous: Hot flushes, leg cramps, abnormal vision, anaphylactoid reaction.

Laboratory Test Alterations: ALT, AST, BUN, NPN, alkaline phosphatase. HDL.

Overdose Management: Symptoms: Severe hypotension, bradycardia, cardiac insufficiency, cardiogenic shock, cardiac arrest, generalized seizures respiratory problems, bronchospasms, vomiting, lapse of consciousness. Treatment: Place the client in a supine position and monitor carefully and treat under intensive care conditions. Treatment should continue for a long enough period of time consistent with the 7- to 10-hr half-life of the drug. Gastric lavage or induced emesis shortly after ingestion For excessive bradycardia, atropine, 2 mg IV. If the bradycardia is resistant to therapy, perform pacemaker therapy. To support cardiovascular function, give glucagon, 5-10 mg IV rapidly over 30 sec, followed by a continuous infusion of 5 mg/hr. Sympathomimetics (dobutamine, isoproterenol, epinephrine) may be given. For peripheral vasodilation, give epinephrine or norepinephrine with continuous monitoring of circulatory conditions. For bronchospasm, give beta sympathomimetics as aerosol or IV or give aminophylline IV. In the event of seizures, give a slow IV injection of diazepam or clonazepam.

Drug Interactions: Antidiabetic agents / The beta-blocking effect may the hypoglycemic effects Calcium channel blocking agents / Risk of conduction disturbances Clonidine / Potentiation of BP and heart rate lowering effects Cyclosporine / Cyclosporine blood levels due to liver breakdown Digoxin / Digoxin levels Rifampin / Plasma levels of carvedilol

How Supplied: Tablet: 3.125 mg, 6.25 mg, 12.5 mg, 25 mg

Dosage
?Tablets Essential hypertension.
Initial: 6.25 mg b.i.d. If this is tolerated, using standing systolic pressure measured about 1 hr after dosing, maintain the dose for 7-14 days. Then increase to 12.5 mg b.i.d., if necessary, based on trough BP, using standing systolic pressure 2 hr after dosing. This dose should be maintained for 7-14 days and can then be adjusted upward to 25 mg b.i.d. if necessary and tolerated. The total daily dose should not exceed 50 mg.
Congestive heart failure.
Initial: 3.125 mg b.i.d. for 2 weeks. If this is tolerated, increase to 6.25 mg b.i.d. Dosing is doubled every 2 weeks to the highest tolerated level, up to a maximum of 25 mg b.i.d. in those weighing less than 85 kg and 50 mg b.i.d. in those weighing over 85 kg.
Angina pectoris.
25-50 mg b.i.d.
Idiopathic cardiomyopathy.
6.25-25 mg b.i.d.