Metoprolol

Metoprolol is a prescription medication used to treat the symptoms of Hypertension, Acute Myocardial Infarction, Congestive Heart Failure, Angina.

• Metoprolol is available under the following different brand names: Lopressor, Toprol XL, Kapspargo Sprinkle

Dosages of Metoprolol:

Adult and Pediatric dosage

Injectable solution (as tartrate)

• 1mg/1mL

Tablet (as tartrate)

• 25mg (generic)
• 50mg (generic, Lopressor)
• 100mg (generic, Lopressor)

Tablet, extended-release (Toprol XL [as succinate])

• 25mg
• 50mg
• 100mg
• 200mg

Capsule, extended-release (Kapspargo Sprinkle [as succinate])

• 25mg
• 50mg
• 100mg
• 200mg

Hypertension

Lopressor

Adults

• 100 mg/day orally initially in a single dose or divided every 12 hours; may be increased at intervals of 1 week or longer; not to exceed 450 mg/day

Pediatric

• Children 1-17 years: 1-2 mg/kg/day orally divided twice daily; not to exceed 6 mg/kg/day not to exceed 200 mg/day

Toprol XL

Adults

• 25-100 mg orally once daily initially; may be increased at intervals of 1 week or longer; usual range, 50-100 mg/day; not to exceed 400 mg/day

Pediatric

• Children 6 years of age or older: 1 mg/kg orally daily; not to exceed 50 mg/day initially; adjusted on basis of patient response; not to exceed 2 mg/kg/day not to exceed 200 mg/day

Kapspargo Sprinkles

Adults 

• Initial dose: 25-100 mg orally once daily in a single dose; adjust dosage at weekly (or longer) intervals until optimum blood pressure reduction is achieved
• Dosage above 400 mg/day not studied

Pediatric

• Children younger than 6 years of age: safety and efficacy not established
• Children 6 years of age or older: 1 mg/kg orally once daily, do not exceed 50 mg daily; adjust dosage according to blood pressure response
• Doses over 2 mg/kg (or over 200 mg) every day not studied 

Acute Myocardial Infarction

Early treatment

Lopressor

• 5 mg rapid IV every 2 minutes, up to 3 doses; then, 15 minutes after the last IV, 50 mg orally every 6 hours for 48 hours; then 50-100 mg orally every 12 hours
• If full IV dose is not tolerated: 25-50 mg orally every 6 hours after the last IV

Congestive Heart Failure

Toprol XL

• 25 mg orally once per day initially; increased every 2 weeks as needed; target dosage 200 mg/day
• New York Heart Association (NYHA) greater than class II: Reduce dosage 12.5 mg/day

Kapspargo Sprinkle

• Before initiation, stabilize dose of other heart failure drug therapy and ensure the patient is not fluidly overloaded
• Initial dose: 25 mg orally once daily for 2 weeks
• Not suitable for initial therapy in patients who are expected to require a starting dose of less than 25 mg/day
• Individualized dose and closely monitor during up-titration; double dose every 2 weeks to the highest dose level tolerated or up to 200 mg

Angina

Lopressor

• 100 mg/day orally initially divided every 12 hours; may be increased at intervals of 1 week or longer; not to exceed 400 mg/day

Toprol XL

• 100 mg/day orally initially; may be increased at intervals of 1 week or longer; not to exceed 400 mg/day

Kapspargo Sprinkle

• Usual initial dose: 100 mg orally once a day, given in a single dose; gradually increase the dose at weekly intervals until an optimum clinical response is achieved or there is a pronounced slowing of the heart rate
• Dosages above 400 mg/day have not been studied
• If treatment is to be discontinued, gradually reduce the dose over a period of 1-2 weeks

Dosage Considerations – Should be Given as Follows: 

• See “Dosages”.

Common side effects of Metoprolol include:

• dizziness, 
• tiredness, 
• depression, 
• confusion, 
• memory problems, 
• nightmares, 
• trouble sleeping, 
• diarrhea, 
• mild itching, and
• rash

Serious side effects of Metoprolol include:

• hives, 
• difficulty breathing, 
• swelling of the face, lips, tongue, or throat, 
• very slow heartbeats, 
• lightheadedness, 
• shortness of breath, 
• swelling, 
• rapid weight gain, and
• cold feeling in the hands and feet

Rare side effects of Metoprolol include:

• none 

If your medical doctor is using this medicine to treat your pain, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them.  Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider, or pharmacist first

• Metoprolol has severe interactions with no other drugs.
• Metoprolol has serious interactions with at least 33 other drugs. 
• Metoprolol has moderate interactions with at least 202 other drugs.
• Metoprolol has minor interactions with at least 32 other drugs. 

This information does not contain all possible interactions or adverse effects.  Visit the RxList Drug Interaction Checker for any drugs interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use.  Keep a list of all your medications with you, and share this information with your doctor and pharmacist.  Check with your health care professional or doctor for additional medical advice, or if you have health questions, concerns.

Contraindications

• Documented hypersensitivity

Lopressor

• Hypertension and angina: Sinus bradycardia, 2°/3° heart block, cardiogenic shock, sick sinus syndrome (unless permanent pacemaker in place), severe peripheral vascular disease, pheochromocytoma
• Myocardial infarction: Severe sinus bradycardia, heart rate less than 45 beats/min, systolic BP less than 100 mmHg, significant first-degree heart block ((PR interval at least 0.24 seconds), 2°/3° heart block, moderate-to-severe cardiac failure

Toprol XL

• Second- and third-degree heart block, decompensated heart failure, sick sinus syndrome (except in patients with functioning artificial pacemaker), severe bradycardia, cardiogenic shock

Kapspargo Sprinkle

• Severe bradycardia, second- or third-degree heart block, cardiogenic shock, decompensated heart failure, sick sinus syndrome (unless a permanent pacemaker is in place), and in patients who are hypersensitive to any component of this product

Effects of drug abuse

• None

Short-Term Effects

• See “What Are Side Effects Associated with Using Metoprolol?”

Long-Term Effects

• See “What Are Side Effects Associated with Using Metoprolol?”

Cautions

• Use with caution in cerebrovascular insufficiency, CHF, cardiomegaly, myasthenia gravis, hyperthyroidism or thyrotoxicosis (may mask signs or symptoms), liver disease, renal impairment, peripheral vascular disease, psoriasis (may cause exacerbation of psoriasis)
• May exacerbate bronchospastic disease; monitor closely
• Beta-blockers can cause myocardial depression and may precipitate heart failure and cardiogenic shock
• Sudden discontinuance can exacerbate angina and lead to MI and ventricular arrhythmias in patients with CAD
• Worsening cardiac failure may occur during up-titration of metoprolol succinate; if such symptoms occur, increase diuretics and restore clinical stability before advancing the dose of metoprolol succinate; it may be necessary to lower the dose of metoprolol succinate or temporarily discontinue it
• Bradycardia, including sinus pause, heart block, and cardiac arrest, has been reported; patients with 1° atrioventricular block, sinus node dysfunction, or conduction disorders may be at increased risk
• Increased risk of stroke after surgery
• May potentiate hypoglycemia in patients with diabetes mellitus and may mask signs and symptoms
• Avoid starting a high-dose regimen of extended-release metoprolol in patients undergoing noncardiac surgery; use in patients with cardiovascular risk factors is associated with bradycardia, hypotension, stroke, and death
• Long-term beta-blockers should not be routinely withdrawn before major surgery; however, the impaired ability of the heart to respond to reflex adrenergic stimuli may augment risks of general anesthesia and surgical procedures
• Metoprolol loses beta-receptor selectivity at high doses and in poor metabolizers
• If the drug is administered for tachycardia secondary to pheochromocytoma, it should be given in combination with an alpha-blocker (which should be started before metoprolol is started)
• While taking beta-blockers, patients with a history of severe anaphylactic reaction to a variety of allergens may be more reactive to repeated challenge
• Extended-release tablet should not be withdrawn routinely before major surgery
• Hydrochlorothiazide can cause an idiosyncratic reaction, resulting in acute transient myopia and acute angle-closure glaucoma, which can lead to permanent vision loss if not treated; discontinue hydrochlorothiazide as rapidly as possible if symptoms occur; prompt medical or surgical treatments may need to be considered if the intraocular pressure remains uncontrolled; risk factors for developing acute angle-closure glaucoma may include the history of sulfonamide or penicillin allergy
• Caution in patients with a history of psychiatric illness; may cause or exacerbate CNS depression
• Beta-blockers can precipitate or aggravate symptoms of arterial insufficiency in patients with peripheral vascular disease

Drug interactions overview

• Catecholamine depleting drugs (eg, reserpine, monoamine oxidase (MAO) inhibitors) may have an additive effect when given with beta-blocking agents; monitor when coadministration with catecholamine depleting drugs for evidence of hypotension or marked bradycardia, which may produce vertigo, syncope, or postural hypotension
• While taking beta-blockers, patients with a history of severe anaphylactic reactions to a variety of allergens may be more reactive to repeated challenges and may be unresponsive to the usual doses of epinephrine used to treat an allergic reaction
• Drugs that are strong inhibitors of CYP2D6, such as quinidine, fluoxetine, paroxetine, and propafenone, were shown to double metoprolol concentrations; no information about moderate or weak inhibitors, but are likely to increase metoprolol concentration; closely monitor patients when the combination cannot be avoided
• Digitalis glycosides, clonidine, diltiazem, and verapamil slow atrioventricular conduction and decrease heart rate
• Concomitant administration of hydralazine may inhibit presystemic metabolism of metoprolol leading to increased concentrations of metoprolol
• Concomitant use with beta-blockers can increase the risk of bradycardia; if clonidine and a beta-blocker, such as metoprolol are coadministered, withdraw the beta-blocker several days before the gradual withdrawal of clonidine because beta-blockers may exacerbate the rebound hypertension that can follow the withdrawal of clonidine
• If replacing clonidine with beta-blocker therapy, delay introduction of beta-blockers for several days after clonidine administration has stopped
• Metoprolol succinate is released faster from Kapspargo Sprinkle in the presence of alcohol; may increase the risk for adverse events associated with Kapspargo Sprinkle
• Avoid alcohol consumption

Pregnancy and Lactation

• There are no adequate and well-controlled studies on pregnant women
• Limited data on the use of metoprolol in pregnant women
• Risk to fetus/motor is unknown; because animal reproduction studies are not always predictive of human response, use if needed
•  Lopressor is excreted in breast milk in a very small quantity
• An infant consuming 1 liter of breast milk daily would receive a dose of less than 1 mg of the drug