Beta blockers · Cardiovascular
Metoprolol
metoprolol tartrate · metoprolol succinate · Lopresor® · Toprol-XL®(brand names vary by market)
The workhorse cardioselective beta blocker, in fast and slow clothing.
Also: modified release, injection
Mechanism
Competitive antagonist at beta-1 adrenergic receptors: slows sinus rate, slows AV conduction, reduces contractility, and lowers renin release.
Open the interactive pathwayIndications
- Hypertension
- Angina
- Rate control in atrial fibrillation
- Heart failure with reduced ejection fraction (succinate)
- Post myocardial infarction
Formulations
Dosing concepts
Formulation matters
Tartrate is immediate-release and dosed more than once daily; succinate is extended-release and dosed once daily. The heart-failure evidence is with succinate.
Heart failure
Start low and up-titrate slowly; beta blockade is introduced when the patient is euvolemic and stable, not during acute decompensation.
Concepts, not prescribing instructions. Practice numbers live in current references and local protocols.
Pharmacokinetics
- Bioavailability
- ~50% (extensive first-pass)
- Half-life
- 3-7 h (IR); extended by the succinate matrix
- Elimination
- hepatic: CYP2D6 substrate; poor metabolizers see higher exposure
Lipophilic, crosses the blood-brain barrier more than atenolol, which is why vivid dreams appear on its adverse-effect list.
Play with these concepts in the PK LabAdverse effects
- Bradycardiacommon & serious
- Fatiguecommon
- Hypotension, dizzinesscommon
- Bronchospasm in reactive airway diseaseseriousCardioselectivity is relative, not absolute, and fades at higher doses.
- Masking of hypoglycemia symptomsseriousTremor and palpitations are blunted; sweating persists.
- Vivid dreams, sleep disturbancecommon
Contraindications & precautions
Contraindications
- Severe bradycardia or high-grade AV block without a pacemaker
- Decompensated heart failure
- Severe hypotension
Precautions
- Asthma and COPD
- Diabetes with hypoglycemia unawareness
- Peripheral arterial disease
- Abrupt discontinuation (rebound tachycardia and ischemia)
Interactions
Monitoring
Heart rate
The pharmacodynamic effect you titrate against · Baseline and at every dose change
Blood pressure
Hypotension limits titration
Symptoms: fatigue, exercise tolerance, orthostasis
Effectiveness and tolerability read at the bedside
Counselling points
- Take it at the same time every day; extended-release tablets are swallowed whole, not crushed or chewed.
- Do not stop it suddenly: the dose is tapered if it needs to come off.
- You may feel more tired in the first weeks; this usually settles.
- Check your pulse if you feel faint or unusually slow.
Clinical pearls
- Same molecule, two drugs: tartrate and succinate are not interchangeable milligram for milligram in heart failure.
- A resting heart rate in the 50s is acceptable if the patient feels well; treat the patient, not the number.
References & review
- Metoprolol product monograph (consult the current version for your market) (monograph)
- Goodman & Gilman's The Pharmacological Basis of Therapeutics, 14th ed. (reference-work)
Last reviewed 2026-08-15 · jurisdiction: global · drug information changes; verify against current references before practice use.