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Lopressor: Full Drug Profile

Medically reviewed by Min Clinic Staff | Updated: January 2026

Lopressor - General Information

A selective adrenergic beta-1-blocking agent with no stimulatory action. It&

 

Pharmacology of Lopressor

Lopressor, a competitive, beta1-selective (cardioselective) adrenergic antagonist, is similar to atenolol in its moderate lipid solubility, lack of intrinsic sympathomimetic activity (ISA), and weak membrane stabilizing activity (MSA).

 

Lopressor for patients

Metoprolol succinate is used to treat high blood pressure alone or in combination with other medications. This medication can also be used to treat a heart condition called angina. This particular formulation is an extended release product, meaning it can be taken once a day. This medication should be taken as directed, with a meal or right after a meal. The tablets should not be broken or crushed. Do not take a double dose if a dose is missed. This medication should not be stopped abruptly; it should be discontinued slowly over time. If you are taking this medication for high blood pressure, make sure to have your blood pressure checked regularly. If you ever have trouble breathing, call your physician immediately. The most common adverse effects are dizziness and tiredness. It is important to inform all your healthcare providers that you are taking this medication, especially before any surgeries or procedures.

 

Lopressor Interactions

Catecholamine-depleting drugs (e.g., reserpine) may have an additive effect when given with beta-blocking agents. Patients treated with extended release metoprolol succinate plus a catecholamine depletor should therefore be closely observed for evidence of hypotension or marked bradycardia, which may produce vertigo, syncope, or postural hypotension.

 

Lopressor Contraindications

Hypertension and Angina: Extended release metoprolol succinate is contraindicated in sinus bradycardia, heart block greater than first degree, cardiogenic shock, and overt cardiac failure

 

Additional information about Lopressor

Lopressor Indication: For the treatment of hypertension and angina pectoris. Mechanism Of Action: Like betaxolol and atenolol, metoprolol competes with adrenergic neurotransmitters such as catecholamines for binding at beta(1)-adrenergic receptors in the heart and vascular smooth muscle. Beta(1)-receptor blockade results in a decrease in heart rate, cardiac output, and blood pressure. Drug Interactions: Acetohexamide The beta-blocker decreases the symptoms of hypoglycemiaChlorpropamide The beta-blocker decreases the symptoms of hypoglycemiaCimetidine Cimetidine increases the effect of the beta-blockerClonidine Increased hypertension when clonidine stoppedDisopyramide The beta-blocker increases toxicity of disopyramideGliclazide The beta-blocker decreases the symptoms of hypoglycemiaGlipizide The beta-blocker decreases the symptoms of hypoglycemiaGlisoxepide The beta-blocker decreases the symptoms of hypoglycemiaGlibenclamide The beta-blocker decreases the symptoms of hypoglycemiaGlycodiazine The beta-blocker decreases the symptoms of hypoglycemiaInsulin The beta-blocker decreases the symptoms of hypoglycemiaLidocaine The beta-blocker increases the effect and toxicity of lidocainePropafenone Propafenone increases the effect of beta-blockerRepaglinide The beta-blocker decreases the symptoms of hypoglycemiaRifampin Rifampin decreases the effect of the metabolized beta-blockerTelithromycin Telithromycin may possibly increase metoprolol effectTolazamide The beta-blocker decreases the symptoms of hypoglycemiaTolbutamide The beta-blocker decreases the symptoms of hypoglycemiaAmobarbital The barbiturate decreases the effect of metabolized beta-blockerAprobarbital The barbiturate decreases the effect of metabolized beta-blockerButalbital The barbiturate decreases the effect of metabolized beta-blockerButabarbital The barbiturate decreases the effect of metabolized beta-blockerButethal The barbiturate decreases the effect of metabolized beta-blockerDihydroquinidine barbiturate The barbiturate decreases the effect of metabolized beta-blockerHeptabarbital The barbiturate decreases the effect of metabolized beta-blockerHexobarbital The barbiturate decreases the effect of metabolized beta-blockerMethohexital The barbiturate decreases the effect of metabolized beta-blockerMethylphenobarbital The barbiturate decreases the effect of metabolized beta-blockerPentobarbital The barbiturate decreases the effect of metabolized beta-blockerPhenobarbital The barbiturate decreases the effect of metabolized beta-blockerPrimidone The barbiturate decreases the effect of metabolized beta-blockerQuinidine barbiturate The barbiturate decreases the effect of metabolized beta-blockerSecobarbital The barbiturate decreases the effect of metabolized beta-blockerTalbutal The barbiturate decreases the effect of metabolized beta-blockerCitalopram The SSRI increases the effect of the beta-blockerEscitalopram The SSRI increases the effect of the beta-blockerFluoxetine The SSRI increases the effect of the beta-blockerSertraline The SSRI increases the effect of the beta-blockerParoxetine The SSRI increases the effect of the beta-blockerDihydroergotamine Ischemia with risk of gangreneDihydroergotoxine Ischemia with risk of gangreneErgonovine Ischemia with risk of gangreneErgotamine Ischemia with risk of gangreneMethysergide Ischemia with risk of gangreneVerapamil Increased effect of both drugsHydralazine Increased effect of both drugsDiltiazem Increased risk of bradycardiaEpinephrine Hypertension, then bradycardiaFenoterol AntagonismFormoterol AntagonismIsoproterenol AntagonismOrciprenaline AntagonismPirbuterol AntagonismPrazosin Risk of hypotension at the beginning of therapyProcaterol AntagonismSalbutamol AntagonismSalmeterol AntagonismTerbutaline AntagonismIbuprofen Risk of inhibition of renal prostaglandinsIndomethacin Risk of inhibition of renal prostaglandinsPiroxicam Risk of inhibition of renal prostaglandins Food Interactions: Avoid alcohol.Take with food.Avoid natural licorice. Generic Name: Metoprolol Synonyms: Metoprolol Tartrate; Metoprolol succinate Drug Category: Sympatholytics; Antihypertensive Agents; Antiarrhythmic Agents; Adrenergic Agents Drug Type: Small Molecule; Approved; Investigational Other Brand Names containing Metoprolol: Beloc; Betaloc; Lopressor HCT; Lopresor; Lopresoretic; Lopressor; Metroprolol; Prelis; Selo-Zok; Seloken; Selopral; Toprol; Toprol-XL; Absorption: Rapid and complete, 50% Toxicity (Overdose): LD50=5500 mg/kg (orally in rats), toxic effects include bradycardia, hypotension, bronchospasm, and cardiac failure. LD50=2090 mg/kg (orally in mice) Protein Binding: 12% Biotransformation: Primarily hepatic Half Life: 3-7 hours Dosage Forms of Lopressor: Solution IntravenousLiquid IntravenousTablet, extended release OralTablet Oral Chemical IUPAC Name: 1-[4-(2-methoxyethyl)phenoxy]-3-(propan-2-ylamino)propan-2-ol Chemical Formula: C15H25NO3 Metoprolol on Wikipedia: https://en.wikipedia.org/wiki/Metoprolol Organisms Affected: Humans and other mammals