Metoprolol Tartrate

Cardiovascular Drug

Drug class: Beta blockers

Metoprolol Tartrate (LOPRESSOR) (中文：美托洛爾)

Pronunciation

Metoprolol tartrate 100mg

Metoprolol tartrate 50mg

Common Strengths of Metoprolol

Metoprolol is available in the following strengths:

• Immediate-release tablets (Metoprolol tartrate): 25 mg, 50 mg, 100 mg [1]
• Extended-release tablets (metoprolol succinate): 25 mg, 50 mg, 100 mg, 200 mg [1]

Drug Trade Name of Metoprolol

The brand names for metoprolol include:

• Lopressor (immediate-release metoprolol tartrate tablets)
• Betaloc Zok (extended-release metoprolol succinate tablets) [1]

Mechanism of Action

Metoprolol is a β1-selective (cardioselective) beta-blocker. It works by blocking the action of epinephrine (adrenaline) on beta-1 receptors in the heart. This slows the heart rate, reduces force of heart contractions, oxygen demand and decreases blood pressure. [1][3]

Route of Administration

Metoprolol is available for:

• Oral administration as immediate-release and extended-release tablets
• Intravenous injection (given by healthcare providers) [1][2]

Dosages

• Hypertension
  • Immediate-release: Typical starting 50 mg once daily, up to 400 mg/day maximum
  • Extended-release: Typical starting 100 mg once daily, up to 400 mg/day maximum [1]
• Heart failure: dosage not specified
  • Immediate-release: Typical 25-100 mg twice daily
  • Extended-release: Typical 25-200 mg once daily [3]
• Diabetic kidney disease: Dosage not specified, adjust based on patient response.

Side Effects

Frequency	Adverse reactions
Very common (≥1/10)	Bradycardia (slow heart rate)
Common (≥1/100 to <1/10)	Dizziness
	Fatigue
	Memory problems
	Diarrhea [1][2]
Uncommon (≥1/1,000 to <1/100)	Depression
	Confusion
	Insomnia
	Rash [2]
Rare (≥1/10,000 to <1/1,000)	Nightmares [2]

Pharmacokinetics

• Well absorbed from GI tract
• Peak plasma levels in 2-4 hours
• Extensively metabolized in liver
• Elimination half-life 6-7 hours
• Excreted in urine [3]

Drug Management

Safety

Metoprolol has a boxed warning about not stopping it suddenly, as it may worsen chest pain, increase blood pressure, or cause a heart attack. Stopping should be done gradually under medical supervision. [1]

Contraindicated in heart block, sick sinus syndrome, severe bradycardia, severe circulation problems, severe heart failure.

Caution in asthma, COPD, diabetes, liver disease. [1][2]

Pregnancy

Metoprolol is classified as pregnancy category C. It should only be used if the potential benefit justifies the potential risk to the fetus. [2]

Breast Feeding

Present in breast milk at low levels. Caution advised as it may cause effects in infant. [2]

Children and Elderly

• Children: Dosage not established

• Elderly: May need lower doses due to age-related decreased kidney function

Renal Impairment

No dosage adjustment provided in labeling. Use with caution in severe renal impairment. [2]

Monitoring Requirements

Monitor blood pressure, heart rate, signs of worsening heart failure, bronchospasm, and blood glucose levels (in diabetics) during metoprolol therapy. [2][3]

Drug Interactions

Metoprolol can interact with calcium channel blockers, digoxin, epinephrine (adrenaline), antidepressants, antipsychotics, anesthetics, and many other drugs. Careful monitoring is required. [1][2]

FAQs

How should I take the tablet?

Take orally with or without food as prescribed. Swallow extended-release capsules whole. [2]

What should I avoid while taking?

Avoid driving or hazardous tasks until you know how metoprolol affects you. Avoid alcohol and decongestants as these may increase some side effects. [2]

What happens if I miss a dose?

Take the missed dose as soon as you remember. If it's near the next dose time, skip the missed dose and continue your regular schedule. Do not double the dose. [2]

Reference

[1] https://www.medicalnewstoday.com/articles/metoprolol-oral-tablet

[2] https://www.drugs.com/metoprolol.html

[3] https://go.drugbank.com/drugs/DB00264

[4] https://www.ncbi.nlm.nih.gov/books/NBK532923/

[5] https://www.webmd.com/drugs/2/drug-11207/metoprolol-tartrate-oral/details