Cardioselective β1-blocker Pregnancy: No well-controlled studies in pregnant women — metoprolol may only be used during pregnancy if the benefits to the mother outweigh the risk to the embryo/foetus. Beta blockers reduce placental perfusion and may cause foetal death and premature birth; prolonged delivery and foetal/neonatal bradycardia reported. Use the lowest possible dose and discontinue treatment 48-72 hours before the calculated birth date; if not possible, monitor the newborn for 48-72 hours post partum. Breast-feeding: milk concentration approximately three times maternal plasma — monitor the breastfed infant for signs of beta blockade.

Metoprolol tartrate

Brand names: Betaloc, Lopresor

Metoprolol tartrate is the immediate-release, shorter-acting salt of the beta-1-selective adrenoceptor blocker metoprolol, used for hypertension, angina, arrhythmias and migraine prophylaxis.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: Hypertension: initially 100 mg daily, increased if necessary to 200 mg daily in single or divided doses

Route: Oral — tablets should be taken on an empty stomach

Frequency: Once daily, or in divided doses (indication-dependent — see notes)

Max: 400 mg per day (the dose must always be adjusted to individual requirements but should not exceed 400 mg/day)

Other adult indications from eMC §4.2 — Angina pectoris: usually 50-100 mg twice daily; the dose may be further increased or combined with nitrates. Tachycardiac arrhythmias: a daily dose of 100-200 mg is usually sufficient, increased if necessary. After acute intravenous treatment of myocardial infarction: orally, therapy should commence 15 minutes after the last intravenous injection with 50 mg every 6 hours for 48 hours. Prophylaxis after myocardial infarction: maintenance dose 100 mg twice daily. Prophylaxis of migraine: 50-100 mg twice daily. Combination with another antihypertensive agent may be considered to further reduce blood pressure. Hepatic impairment: usually the same dose as in normal hepatic function; consider dose reduction only with signs of severely impaired hepatic function (e.g. shunt-operated patients). Elderly: no adequate data above age 80 — take special precautions when increasing the dose; caution as a fall in blood pressure or excessive bradycardia may have more pronounced effects. Beta-blocker treatment must not be suddenly discontinued — where possible reduce gradually over at least two weeks, diminishing to 25 mg for the last 6 days. Note the US label directs administration with or immediately following meals, which differs from the eMC empty-stomach instruction — verify against the specific product SPC. Paediatric population: eMC §4.2 states there is limited data on the use of metoprolol in children and adolescents, therefore the use of metoprolol tartrate is not recommended (US labelling: safety and effectiveness have not been established in paediatric patients); no paediatric dose is given — refer to a children's formulary.

Dose adjustments

Renal

The rate of elimination is insignificantly affected by renal function and therefore no dose adjustment is needed (eMC §4.2).

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to metoprolol, other beta blockers or to any of the excipients
Grade II or III atrioventricular block; higher grade sinoatrial block; sick sinus syndrome
Unstable or acute decompensated heart failure (pulmonary oedema, hypoperfusion or hypotension) requiring continuous or periodical intravenous inotropic beta receptor agonist therapy
Manifest and clinically significant sinus bradycardia (source states heart frequency 50/min); cardiogenic shock
Severe peripheral arterial disease
Hypotension (source states systolic 90 mmHg); metabolic acidosis
Severe bronchial asthma or chronic obstructive pulmonary disease
Suspected acute myocardial infarction with heart rate 50 beats/min, PQ interval 0.24 seconds or systolic blood pressure 100 mmHg — note the mathematical comparison operators were stripped from the extracted source text, so verify these thresholds against the SPC
Concomitant intravenous calcium blockers of the verapamil or diltiazem type, or other antiarrhythmics such as disopyramide (exception: intensive care unit)
Untreated phaeochromocytoma

Side effects

Fatigue (most commonly reported adverse reaction)
Dizziness and headache
Bradycardia, palpitations, balance disturbances (very rarely with associated syncope)
Pronounced blood pressure drop and orthostatic hypotension (very rarely with syncope); cold hands and feet
Nausea, abdominal pain, diarrhoea, constipation
Very rare: gangrene in patients with severe peripheral circulatory disorder, thrombocytopenia and agranulocytosis

Interactions

Intravenous verapamil- or diltiazem-type calcium blockers and other antiarrhythmics (e.g. disopyramide) — concomitant administration is contraindicated outside intensive care (eMC §4.3)
Beta-2 agonists — if an asthmatic uses a beta-2 agonist when initiating metoprolol, the beta-2 agonist dose must be controlled and increased if necessary (eMC §4.4)
Sulfonylureas and other diabetes treatments — metoprolol may reduce the effect of diabetes treatment, mask hypoglycaemia symptoms, and further increase the risk of severe hypoglycaemia with sulfonylureas (eMC §4.4)
Adrenaline — treatment does not always give the desired therapeutic effect in individuals receiving beta blockers (eMC §4.4)
US labelling: catecholamine-depleting drugs (e.g. reserpine, MAO inhibitors) may have an additive effect — observe for hypotension or marked bradycardia
US labelling: strong CYP2D6 inhibitors (quinidine, fluoxetine, paroxetine, propafenone) were shown to double metoprolol concentrations
US labelling: glycosides, clonidine, diltiazem and verapamil with beta-blockers can increase the risk of bradycardia; beta-blockers may exacerbate rebound hypertension after clonidine withdrawal

Clinical monograph

How it works

It selectively blocks cardiac beta-1 adrenoceptors, reducing heart rate, contractility and atrioventricular conduction, thereby lowering cardiac workload, blood pressure and myocardial oxygen demand.

Prescribing in practice

It should not be stopped abruptly, as sudden withdrawal can precipitate rebound tachycardia, worsening angina or myocardial infarction; doses should be tapered.
Because the tartrate salt is short-acting it usually requires more frequent dosing than the modified-release succinate form, and the two are not interchangeable on a milligram-for-milligram basis.
Beta-1 selectivity is relative and is lost at higher doses, so caution is needed in bronchospastic disease, and it can mask the warning signs of hypoglycaemia in diabetes.

Monitoring

Monitor heart rate and blood pressure for therapeutic effect and for excessive bradycardia or hypotension, particularly during dose titration.

Counselling the patient

Do not stop this medicine suddenly; your doctor will reduce the dose gradually if it needs to be stopped.
It may cause tiredness, cold hands and feet, or a slow pulse; report a very slow heartbeat or fainting.
If you have diabetes, be aware it can hide some warning signs of low blood sugar such as a fast heartbeat.

Evidence & guidelines

Beta-blockers such as metoprolol are established agents in NICE guidance for angina and rate control of arrhythmias; mortality benefit in chronic heart failure is best evidenced for the modified-release succinate formulation.

Reference: ESC; NICE NG106; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways