Metoprolol is a beta-blocker that improves blood flow and circulation by relaxing blood vessels and slowing the heart rate. It is used to treat chest pain, heart failure, hypertension, myocardial infarction, and atrial fibrillation.
Generic names: Metoprolol succinate (extended-release), metoprolol tartrate
Brand names: Toprol, Toprol-XL (extended-release), Lopressor
Pharmacologic class: Beta-adrenergic blocker
Therapeutic class: Antihypertensive, antianginal
Mechanism of action: Metoprolol blocks beta1-receptors (heart) without effect on beta2-receptors (lungs, uterus, smooth muscle). Metoprolol decreases cardiac output and reduces heart rate.
Indications for use: Hypertension, angina, heart failure. Off-label uses include ventricular arrhythmias, tachycardia, tremors, and anxiety.
Precautions and contraindications: Do not use with bradycardia, second or third-degree heart blocks, or systolic blood pressure below 100 mm Hg. Take caution in patients with renal or liver impairment. Not for use in children.
- Metoprolol coupled with alpha-adrenergics like amphetamines, epinephrine, and pseudoephedrine can cause excessive hypertension with bradycardia
- Digoxin and metoprolol can cause severe bradycardia
- Insulin or oral hypoglycemics with metoprolol can alter the efficiency of each other
- Metoprolol with MAOIs can cause hypertension
- Metoprolol taken with other antihypertensives can have severe hypotensive effects
- Fatigue, weakness, dizziness, drowsiness, insomnia, changes in mental status
- Orthostatic hypotension, bradycardia
- Heart failure, pulmonary edema
- Blurred vision, nasal congestion
- Nausea, vomiting, constipation, diarrhea, heartburn, dry mouth
- Urinary frequency, erectile dysfunction, decreased libido
- Hyperglycemia and hypoglycemia
- Wheezing and bronchospasm
Available preparations: IV (tartrate), tablets, extended-release tablets (succinate)
Dosages for adults: Dosage is dependent on use. For hypertension: 50 to 100 mg PO daily or BID. For angina, 100 mg PO daily or BID. For MI, three bolus injections of 5 mg are given 2 minutes apart. If tolerated, a PO dose of 50 mg is given 15 minutes later and then continued every 6 hours for 48 hours, and then 100 mg BID thereafter. For symptomatic heart failure, 25 mg PO daily.
Dosages for children: Safety has not been established.
|PO tablets||15 minutes||1 hour||6-12 hours|
|PO extended||15 minutes||6-12 hours||24 hours|
|IV||Immediate||20 minutes||5-8 hours|
Nursing Considerations for Metoprolol
Related nursing diagnoses
- Decreased cardiac output
- Anxiety (as an off-label use of metoprolol)
- Diarrhea, fatigue, insomnia, etc., as potential side effects of metoprolol
- Assess for an allergy to beta-blockers.
- Assess for chest pain by having the patient rate on a scale of 1-10, and describe characteristics, duration, and frequency.
- Monitor for signs of worsening CHF such as shortness of breath or adventitious lung sounds.
- Assess the patient’s blood pressure and heart rate to ensure the medication is safe to administer and will not worsen hypotension or bradycardia.
- Monitor the effectiveness of metoprolol by reassessing blood pressure or pulse after administration.
- Monitor glucose levels as medication may increase or decrease glucose in diabetic patients.
- When administering IV metoprolol, patients should be monitored through telemetry.
- Administer PO metoprolol after meals for enhanced absorption.
- Administer IV metoprolol undiluted over at least 1 minute.
Patient Teaching Associated with Metoprolol
- Instruct patients on the side effect of orthostatic hypotension. Patients, particularly the elderly, should transition from a lying to a sitting or standing position slowly to prevent a drop in blood pressure and subsequent syncope and falls.
- Monitor for signs of worsening heart failure such as a sudden weight gain or shortness of breath.
- Extended-release tablets are scored and can be divided but the dosage prescribed should not be crushed or chewed.
- Alcohol use with metoprolol may increase hypotensive effects.
- Do not stop abruptly without the guidance of a healthcare provider as withdrawal could occur and result in angina or heart attack.
This is not an all-inclusive list of possible drug interactions, adverse effects, precautions, nursing considerations, or patient instructions. Please consult further with a pharmacist for complete information.
References and Sources
- Morris J, Dunham A. Metoprolol. [Updated 2022 Jan 19]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK532923/
- Schull, P. D. (2013). McGraw-Hill Nurses Drug Handbook, Seventh Edition. McGraw-Hill Education.