atenolol(redirected from Atenalol)
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Pharmacologic class: Beta-adrenergic blocker (selective)
Therapeutic class: Antianginal, anti-hypertensive
Pregnancy risk category D
FDA Box Warning
• Caution patients with coronary artery disease (CAD) not to discontinue drug abruptly, because this may cause severe angina exacerbation, myocardial infarction, and ventricular arrhythmias. (The last two complications may occur with or without preceding angina exacerbation.) With planned drug discontinuation, observe patients carefully and advise them to minimize physical activity; if angina worsens or acute coronary insufficiency develops, drug should be reinstituted promptly, at least temporarily. Because CAD is common and may go unrecognized, abrupt withdrawal may pose a risk even in patients treated only for hypertension.
Selectively blocks beta1-adrenergic (myocardial) receptors; decreases cardiac output, peripheral resistance, and myocardial oxygen consumption. Also depresses renin secretion without affecting beta2-adrenergic (pulmonary, vascular, uterine) receptors.
Tablets: 25 mg, 50 mg, 100 mg
Indications and dosages
Adults: Initially, 50 mg P.O. once daily, increased to 100 mg after 7 to 14 days if needed
➣ Angina pectoris
Adults: Initially, 50 mg P.O. once daily, increased to 100 mg after 7 days if needed. Some patients may require up to 200 mg daily.
➣ Acute myocardial infarction
Adults: 50 mg tablet P.O., then give 50 mg P.O. in 12 hours. Maintenance dosage is 100 mg P.O. daily or 50 mg b.i.d. for 6 to 9 days.
• Renal impairment
• Elderly patients
• Cardiogenic shock
• Sinus bradycardia
• Greater than first-degree heart block
• Heart failure (unless secondary to tachyarrhythmia treatable with beta-adrenergic blockers)
Use cautiously in:
• renal failure, hepatic impairment, pulmonary disease, diabetes mellitus, thyrotoxicosis
• pregnant or breastfeeding patients
☞ Adjust initial and subsequent dosages downward depending on clinical observations, including pulse rate and blood pressure.
☞ Don't discontinue drug suddenly. Instead, taper dosage over 2 weeks.
CNS: fatigue, lethargy, vertigo, drowsiness, dizziness, depression, disorientation, short-term memory loss
CV: hypertension, intermittent claudication, cold arms and legs, orthostatic hypotension, bradycardia, arrhythmias, heart failure, cardiogenic shock, myocardial reinfarction
EENT: blurred vision, dry eyes, eye irritation, conjunctivitis, stuffy nose, rhinitis, pharyngitis, laryngospasm
GI: nausea, vomiting, diarrhea, constipation, gastric pain, flatulence, anorexia, ischemic colitis, retroperitoneal fibrosis, acute pancreatitis, mesenteric arterial thrombosis
GU: impotence, decreased libido, dysuria, nocturia, Peyronie's disease, renal failure
Musculoskeletal: muscle cramps, back and joint pain
Respiratory: dyspnea, wheezing, respiratory distress, bronchospasm, bronchial obstruction, pulmonary emboli
Other: decreased exercise tolerance, allergic reaction, fever, development of antinuclear antibodies, hypersensitivity reaction
Drug-drug. Amiodarone, cardiac glycosides, diltiazem, verapamil: increased myocardial depression, causing excessive bradycardia and heart block
Amphetamines, cocaine, ephedrine, norepinephrine, phenylephrine, pseudoephedrine: excessive hypertension, bradycardia
Ampicillin, calcium salts: decreased antihypertensive and antianginal effects
Aspirin, bismuth subsalicylate, magnesium salicylate, nonsteroidal anti-inflammatory drugs: decreased anti-hypertensive effect
Clonidine: life-threatening blood pressure increase after clonidine withdrawal or simultaneous withdrawal of both drugs
Dobutamine, dopamine: decrease in beneficial beta-cardiovascular effects
Lidocaine: increased lidocaine levels, greater risk of toxicity
MAO inhibitors: bradycardia Prazosin: increased risk of orthostatic hypotension
Reserpine: increased hypotension, marked bradycardia
Theophylline: decreased theophylline elimination
Drug-diagnostic tests. Alanine aminotransferase, alkaline phosphatase, aspartate aminotransferase, antinuclear antibody titer, blood urea nitrogen, creatinine, lactate dehydrogenase, platelets, potassium, uric acid: increased levels
Glucose: increased or decreased level
Insulin tolerance test: false result
Drug-behaviors. Alcohol use: increased hypotension
• Watch for signs and symptoms of hypersensitivity reaction.
• Monitor vital signs (especially blood pressure), ECG, and exercise tolerance.
• Check closely for hypotension in hemodialysis patients.
• Monitor blood glucose level regularly if patient is diabetic; drug may mask signs and symptoms of hypoglycemia.
☞ Instruct patient to immediately report signs and symptoms of allergic response, breathing problems, and chest pain.
• Advise patient to take drug at same time every day.
☞ Inform patient that he may experience serious reactions if he stops taking drug suddenly. Advise him to consult prescriber before discontinuing.
• Caution patient to avoid driving and other hazardous activities until he knows how drug affects concentration and alertness.
• Tell patient that drug may cause a temporary blood pressure decrease if he stands or sits up suddenly. Instruct him to rise slowly and carefully.
• Inform women that drug shouldn't be taken during pregnancy. Urge them to report planned or suspected pregnancy.
• Tell men that drug may cause erectile dysfunction. Advise them to discuss this issue with prescriber.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, and behaviors mentioned above.