Lopresor
metoprolol succinate
metoprolol tartrate
Pharmacologic class: Beta-adrenergic blocker (selective)
Therapeutic class: Antihypertensive, antianginal
Pregnancy risk category C
FDA Box Warning
• Exacerbations of angina pectoris and myocardial infarction (MI) may follow abrupt withdrawal of some beta blockers. When discontinuing long-term therapy, particularly in patients with ischemic heart disease, reduce dosage gradually over 1 to 2 weeks and monitor patient carefully. If angina worsens markedly or acute coronary insufficiency develops, reinstate drug promptly (at least temporarily) and take other appropriate measures to manage unstable angina. Caution patient not to interrupt or discontinue therapy without prescriber's advice. Because coronary artery disease is common and may be unrecognized, it may be prudent not to discontinue drug abruptly even in patients treated only for hypertension.
Action
Blocks stimulation of beta1 (myocardial) adrenergic receptors, usually without affecting beta2 (pulmonary, vascular, uterine) adrenergic receptor sites
Availability
Injection (tartrate): 1 mg/ml
Tablets: 50 mg, 100 mg
Tablets (extended-release, succinate): 25 mg, 50 mg, 100 mg, 200 mg
Indications and dosages
➣ Hypertension
Adults: 50 to 100 mg P.O. daily as a single dose or in two divided doses (conventional tablets) or once daily (extended-release tablets). May be increased q 7 days as needed, up to 450 mg/day (tartrate) or 400 mg (succinate extended-release).
➣ Angina pectoris
Adults: 100 mg P.O. daily as a single dose or in two divided doses (conventional tablets) or once daily (extended-release tablets). May be increased q 7 days as needed, up to 400 mg.
➣ MI
Adults: Three bolus injections of 5 mg I.V. given at 2-minute intervals. If patient tolerates I.V. dose, give 50 mg P.O. 15 minutes after last I.V. dose, and continue P.O. doses q 6 hours for 48 hours. For maintenance, 100 mg P.O. b.i.d. If patient doesn't tolerate full I.V. dose, give 25 to 50 mg P.O. (depending on degree of intolerance), starting 15 minutes after last I.V. dose or when clinical condition allows; discontinue drug if patient shows severe intolerance. As late treatment, 100 mg P.O. b.i.d. when clinical condition allows, continued for at least 3 months.
➣ Symptomatic heart failure
Adults: 25 mg P.O. daily (extended-release tablets) in patients with NYHA Class II heart failure. Dosage may be doubled q 2 weeks, up to 200 mg/day or until highest tolerated dosage is reached. For more severe heart failure, start with 12.5 mg P.O. daily.
Off-label uses
• Ventricular arrhythmias, tachycardia
• Tremors
• Anxiety
Contraindications
• Sinus bradycardia, heart block greater than first degree, cardiogenic shock, overt cardiac failure (with Lopressor used for hypertension or angina)
• Heart rate below 45 beats/minute, second- or third-degree heart block, significant first-degree heart block; systolic pressure below 100 mm Hg; or moderate-to-severe cardiac failure (when Lopressor is used for MI)
• Hypersensitivity to drug or its components, severe bradycardia, heart block greater than first degree, cardiogenic shock, decompensated cardiac failure, sick sinus syndrome (unless permanent pacemaker is in place) (with Toprol-XL)
Precautions
Use cautiously in:
• renal or hepatic impairment, pulmonary disease, diabetes mellitus, thyrotoxicosis
• MAO inhibitor use within past 14 days
• pregnant or breastfeeding patients
• children (safety not established).
Administration
• Give metoprolol tartrate with or immediately after meals, because food enhances its absorption.
• Know that succinate extended-release tablets are scored and can be divided. However, tablet or half-tablet should be swallowed whole and not crushed or chewed.
• For I.V. administration, give each dose undiluted by direct injection over at least 1 minute.
Adverse reactions
CNS: fatigue, weakness, anxiety, depression, dizziness, drowsiness, insomnia, memory loss, mental status changes, nervousness, nightmares
CV: orthostatic hypotension, peripheral vasoconstriction, bradycardia, heart failure, pulmonary edema
EENT: blurred vision, stuffy nose
GI: nausea, vomiting, constipation, diarrhea, flatulence, gastric pain, heartburn, dry mouth
GU: urinary frequency, erectile dysfunction, decreased libido
Hepatic: hepatitis
Metabolic: hyperglycemia, hypoglycemia
Respiratory: wheezing, bronchospasm
Musculoskeletal: back pain, joint pain
Skin: rash
Other: drug-induced lupus syndrome
Interactions
Drug-drug. Amphetamines, ephedrine, epinephrine, norepinephrine, phenylephrine, pseudoephedrine: unopposed alpha-adrenergic stimulation (excessive hypertension, bradycardia)
Antihypertensives, nitrates: additive hypotension
Digoxin: additive bradycardia
Dobutamine, dopamine: reduced cardiovascular benefits of these drugs
General anesthestics, phenytoin (I.V.), verapamil: additive myocardial depression
Insulin, oral hypoglycemics: altered efficacy of these drugs
MAO inhibitors: hypertension
Drug-diagnostic tests. Alanine aminotransferase, alkaline phosphatase, aspartate aminotransferase, blood urea nitrogen, glucose, lactate dehydrogenase, lipoproteins, potassium, triglycerides, uric acid: increased levels
Drug-food. Any food: enhanced drug absorption
Drug-behaviors. Acute alcohol ingestion: additive hypotension
Cocaine use: unopposed alpha-adrenergic stimulation (excessive hypertension, bradycardia)
Patient monitoring
• Measure blood pressure closely when starting therapy and titrating dosage. Once patient stabilizes, measure blood pressure every 3 to 6 months.
• Monitor blood pressure and pulse before I.V. administration. If patient is hypotensive or has bradycardia, consult prescriber before giving dose.
• Watch for orthostatic hypotension in at-risk patients, particularly the elderly.
• Assess glucose levels in diabetic patient. Be aware that drug may mask signs and symptoms of hypoglycemia.
• Monitor for signs and symptoms of hyperthyroidism. Know that drug may mask these. Reduce dosage gradually in hyperthyroid patients.
See When discontinuing drug, reduce dosage gradually over 1 to 2 weeks.
Patient teaching
• Advise patient to take with or immediately after meals.
• Tell patient that extended-release tablets are scored and can be divided, but that he should swallow tablets or half-tablets whole and not crush or chew them.
See Advise patient with heart failure to report signs or symptoms of worsening condition, including weight gain and increasing shortness of breath.
• Caution patient to avoid driving and other hazardous activities until drug effects are known.
• Instruct patient to notify health care providers (including dentists) that he is taking drug before having surgery.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, foods, and behaviors mentioned above.
metoprolol
(me-toe-proe-lole) metoprolol,Betaloc IV
(trade name),Lopresor
(trade name),Lopresor SR
(trade name),Lopressor
(trade name),Toprol-XL
(trade name)Classification
Therapeutic: antianginalsPharmacologic: beta blockers
Indications
Action
Therapeutic effects
Pharmacokinetics
Time/action profile (cardiovascular effects)
| ROUTE | ONSET | PEAK | DURATION |
|---|---|---|---|
| PO† | 15 min | unknown | 6–12 hr |
| PO–ER | unknown | 6–12 hr | 24 hr |
| IV | immediate | 20 min | 5–8 hr |
Contraindications/Precautions
Adverse Reactions/Side Effects
Central nervous system
- fatigue (most frequent)
- weakness (most frequent)
- anxiety
- depression
- dizziness
- drowsiness
- insomnia
- memory loss
- mental status changes
- nervousness
- nightmares
Ear, Eye, Nose, Throat
- blurred vision
- stuffy nose
Respiratory
- bronchospasm
- wheezing
Cardiovascular
- bradycardia (life-threatening)
- HF (life-threatening)
- pulmonary edema (life-threatening)
- hypotension
- peripheral vasoconstriction
Gastrointestinal
- constipation
- diarrhea
- drug-induced hepatitis
- dry mouth
- flatulence
- gastric pain
- heartburn
- ↑ liver enzymes
- nausea
- vomiting
Genitourinary
- erectile dysfunction (most frequent)
- ↓ libido
- urinary frequency
Dermatologic
- rashes
Endocrinologic
- hyperglycemia
- hypoglycemia
Musculoskeletal
- arthralgia
- back pain
- joint pain
Miscellaneous
- drug-induced lupus syndrome
Interactions
Drug-Drug interaction
General anesthesia, IVphenytoin, and verapamil may cause ↑ myocardial depression.↑ risk of bradycardia when used with digoxin, verapamil, diltiazem, or clonidine.↑ hypotension may occur with other antihypertensives, acute ingestion of alcohol, or nitrates.Concurrent use with amphetamines, cocaine, ephedrine, epinephrine, norepinephrine, phenylephrine, or pseudoephedrine may result in unopposed alpha-adrenergic stimulation (excessive hypertension, bradycardia).Concurrent administration of thyroid administration may ↓ effectiveness.May alter the effectiveness of insulins or oral hypoglycemic agents (dose adjustments may be necessary).May ↓ the effectiveness of theophylline.May ↓ the beneficial beta1-cardiovascular effects of dopamine or dobutamine.Use cautiously within 14 days of MAO inhibitor therapy (may result in hypertension).Route/Dosage
When switching from immediate-release to extended-release product, the same total daily dose can be used
Availability (generic available)
Nursing implications
Nursing assessment
- Monitor BP, ECG, and pulse frequently during dose adjustment and periodically during therapy.
- Monitor frequency of prescription refills to determine compliance.
- Monitor vital signs and ECG every 5–15 min during and for several hours after parenteral administration. If heart rate <40 bpm, especially if cardiac output is also decreased, administer atropine 0.25–0.5 mg IV.
- Monitor intake and output ratios and daily weights. Assess routinely for signs and symptoms of HF (dyspnea, rales/crackles, weight gain, peripheral edema, jugular venous distention).
- Angina: Assess frequency and characteristics of anginal attacks periodically during therapy.
- Lab Test Considerations: May cause ↑ BUN, serum lipoprotein, potassium, triglyceride, and uric acid levels.
- May cause ↑ ANA titers.
- May cause ↑ in blood glucose levels.
- May cause ↑ serum alkaline phosphatase, LDH, AST, and ALT levels.
Potential Nursing Diagnoses
Decreased cardiac output (Side Effects)Noncompliance (Patient/Family Teaching)
Implementation
- high alert: IV vasoactive medications are inherently dangerous. Before administering intravenously, have second practitioner independently check original order and dose calculations.
- high alert: Do not confuse Toprol-XL (metoprolol) with Topamax (topiramate). Do not confuse Lopressor with Lyrica. Do not confuse metoprolol tartrate with metoprolol succinate.
- Oral: Take apical pulse before administering. If <50 bpm or if arrhythmia occurs, withhold medication and notify health care professional.
- Administer metoprolol with meals or directly after eating.
- Extended-release tablets should be swallowed whole; do not break, crush, or chew.
Intravenous Administration
- Diluent: Administer undiluted.Concentration: 1 mg/mL.
- Rate: Administer over 1 min.
- Y-Site Compatibility: acyclovir, alemtuzumab, alfentanil, alteplase, amikacin, aminocaproic acid, aminophylline, amiodarone, amphotericin B liposome, anidulafungin, argatroban, ascorbic acid, atropine, azathioprine, aztreonam, benztropine, bivalirudin, bleomycin, bumetanide, buprenorphine, butorphanol, calcium chloride, calcium gluconate, carboplatin, carmustine, caspofungin, cefazolin, cefonocid, cefoperazone, cefotaxime, cefotetan, cefoxitin, ceftaroline, ceftazidime, ceftriaxone, cefuroxime, chloramphenicol, chlorpromazine, cisplatin, clindamycin, cyanocobalamin, cyclophosphamide, cyclosporine, cytarabine, dactinomycin, daptomycin, dexamethasone, dexmedetomidine, digoxin, diltiazem, diphenhydramine, dobutamine, docetaxel, dopamine, doxorubicin, doxycycline, enalaprilat, ephedrine, epinephrine, epirubicin, epoetin alfa, eptifibatide, esmolol, etoposide, etoposide phosphate, famotidine, fenoldopam, fentanyl, fluconazole, fludarabine, fluorouracil, folic acid, furosemide, ganciclovir, gemcitabine, gentamicin, glycopyrrolate, granisetron, heparin, hetastarch, hydrocortisone, hydromorphone, idarubicin, ifosfamide, imipenem/cilastatin, indomethacin, insulin, irinotecan, isoproterenol, ketorolac, labetalol, linezolid, lorazepam, magnesium sulfate, mannitol, mechlorethamine, meperidine, methotrexate, methoxamine, methyldopate, methylprednisolone, metoclopramide, metronidazole, midazolam, milrinone, mitoxantrone, morphine, multivitamins, mycophenolate, nafcillin, nalbuphine, naloxone, nitroprusside, norepinephrine, octreotide, ondansetron, oxacillin, oxaliplatin, oxytocin, paclitaxel, palonosetron, pamidronate, pancuronium, papaverine, pemetrexed, penicillin G, pentamidine, pentazocine, pentobarbital, phenobarbital, phentolamine, phenylephrine, phytonadione, piperacillin/tazobactam, potassium acetate, potassium chloride, procainamide, prochlorperazine, promethazine, propranolol, protamine, pyridoxime, quinupristin/dalfopristin, ranitidine, rocuronium, sodium bicarbonate, streptokinase, succinylcholine, sufentanil, tacrolimus, teniposide, theophylline, thiamine, thiotepa, ticarcillin/clavulanate, tigecycline, tirofiban, tobramycin, tolazoline, trimetaphan, vancomycin, vasopressin, vecuronium, verapamil, vincristine, vinorelbine, voriconazole, zoledronic acid
- Y-Site Incompatibility: allopruinol, amphotericin B cholesteryl, amphotericin B colloidal, amphotericin B lipid complex, dantrolene, diazepam, diazoxide, pantoprazole, phenytoin, trimethoprim/sulfamethoxazole
Patient/Family Teaching
- Instruct patient to take medication as directed, at the same time each day, even if feeling well; do not skip or double up on missed doses. Take missed doses as soon as possible up to 8 hr before next dose. Abrupt withdrawal may precipitate life-threatening arrhythmias, hypertension, or myocardial ischemia.
- Teach patient and family how to check pulse daily and BP biweekly and to report significant changes to health care professional.
- May cause drowsiness. Caution patient to avoid driving or other activities that require alertness until response to the drug is known.
- Advise patient to change positions slowly to minimize orthostatic hypotension.
- Caution patient that this medication may increase sensitivity to cold.
- Instruct patient to notify health care professional of all Rx or OTC medications, vitamins, or herbal products being taken and to consult health care professional before taking any Rx, OTC, or herbal products, especially cold preparations, concurrently with this medication. Patients on antihypertensive therapy should also avoid excessive amounts of coffee, tea, and cola.
- Diabetics should closely monitor blood glucose, especially if weakness, malaise, irritability, or fatigue occurs. Medication does not block sweating as a sign of hypoglycemia.
- Advise patient to notify health care professional if slow pulse, difficulty breathing, wheezing, cold hands and feet, dizziness, light-headedness, confusion, depression, rash, fever, sore throat, unusual bleeding, or bruising occurs.
- Instruct patient to inform health care professional of medication regimen before treatment or surgery.
- Advise patient to carry identification describing disease process and medication regimen at all times.
- Hypertension: Reinforce the need to continue additional therapies for hypertension (weight loss, sodium restriction, stress reduction, regular exercise, moderation of alcohol consumption, and smoking cessation). Medication controls but does not cure hypertension.
Evaluation/Desired Outcomes
- Decrease in BP.
- Reduction in frequency of anginal attacks.
- Increase in activity tolerance.
- Prevention of MI.