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β-blocker + thiazide diuretic Pregnancy: UK SPC section 4.6: 'Timolol maleate/Bendroflumethiazide is contraindicated during pregnancy. (See section 4.3). Both constituents cross the placenta and appear in breast milk therefore breastfeeding is not recommended. Beta-blockers reduce placental perfusion, which may result in intrauterine foetal death, immature and premature deliveries. In addition, adverse effects (especially hypoglycaemia and bradycardia) may occur in foetus and neonate. There is an increased risk of cardiac and pulmonary complications in the neonate in the postnatal period.'

Timolol with bendroflumethiazide

A fixed-dose oral antihypertensive combining timolol (a non-selective beta-blocker) with bendroflumethiazide (a thiazide diuretic), used for hypertension; note this is the systemic tablet, distinct from timolol eye drops.

Adult dose

Dose: Mild to moderate hypertension: recommended dosage range 1 to 4 tablets daily (each tablet contains timolol maleate 10 mg and bendroflumethiazide 2.5 mg). Elderly: initiate treatment with 1 tablet daily and thereafter adjust according to response.
Route: Oral
Frequency: Once daily in the morning, or in two divided doses (morning and evening)
Limited T/A Viatris) section 4.1 is 'the treatment of mild to moderate hypertension' and section 4.2 states 'Timolol maleate/Bendroflumethiazide 10 mg/2.5 mg tablets are for oral use'. STRENGTH (section 2): each tablet contains timolol maleate 10 mg and bendroflumethiazide 2.5 mg; the dose is written in tablets of this strength only. VERBATIM section 4.2: 'The recommended dosage range is 1 to 4 tablets daily. The dosage can be taken in the morning or in two divided doses, morning and evening. If blood pressure control is not achieved on 4 tablets daily, consideration should be given to titrating timolol and bendroflumethiazide separately or adding another agent with hypotensive activity.' 'Dosage in the elderly: Initiate treatment with 1 tablet daily and thereafter adjust according to response.' NO MAXIMUM DOSE is printed as such (4 tablets is the top of the recommended range), so none is given. PAEDIATRIC: 'The safety and efficacy of Timolol maleate/Bendroflumethiazide in children has not been established. No data are available.' No paediatric dose. CONTRAINDICATED IN PREGNANCY (sections 4.3, 4.6). Do not stop suddenly in ischaemic heart disease: reduce gradually over 1-2 weeks (section 4.4). Some sections of the product information we used were incomplete — check the full SPC. Text came from a PDF and has odd spacing in places.

Dose adjustments

Renal

UK SPC section 4.3: severe renal impairment or anuria is a contraindication. Section 4.4: caution in impaired renal function; electrolytes and fluids should be monitored, especially with high doses, long-term use or in renal impairment. No numeric dose adjustment is given.

Hepatic

UK SPC section 4.3: severe hepatic impairment is a contraindication. Section 4.4: caution in impaired hepatic function. No numeric dose adjustment is given.

Dose independently re-sourced from UK Summary of Product Characteristics (SPC) via MHRA Products — clinician-reviewed. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

  • Hypersensitivity to timolol maleate and/or bendroflumethiazide or to any of the excipients (section 4.3)
  • Severe renal impairment or anuria; severe hepatic impairment (section 4.3)
  • Significant electrolyte disturbance including refractory hypokalaemia, hyponatraemia and hypercalcaemia; symptomatic hyperuricaemia; Addison's disease (section 4.3)
  • Uncontrolled heart failure, bradycardia, cardiogenic shock, sick sinus syndrome (including sino-atrial block), second- or third-degree heart block (section 4.3)
  • History of bronchospasm, bronchial asthma or chronic obstructive pulmonary disease (section 4.3)
  • Prinzmetal's angina, untreated phaeochromocytoma, metabolic acidosis, hypotension and severe peripheral circulatory disturbances (section 4.3)
  • Patients receiving adrenergic augmenting drugs (monoamine oxidase inhibitors and tricyclic antidepressants) (section 4.3)
  • Anaesthesia with agents that produce myocardial depression, such as chloroform and ether (section 4.3)
  • Pregnancy (sections 4.3, 4.6)

Side effects

  • Blood and metabolic (section 4.8): blood dyscrasias (including thrombocytopenia, granulocytopenia, aplastic anaemia), haemolytic anaemia; electrolyte depletion and dehydration, hypokalaemia, hyperglycaemia (in diabetic and other susceptible patients), hyperuricaemia, hypercalcaemia; withdrawal syndrome (abrupt withdrawal may precipitate angina in susceptible patients or cause rebound hypertension). The section 4.8 table has only 'Rare' and 'Frequency not known' columns, and the PDF extraction does not show which column each single entry belongs to, so no frequency is stated per reaction
  • Nervous system, eye, ear, cardiovascular (section 4.8): coma (may be precipitated in hepatic cirrhosis), paraesthesia, dizziness, headache, sedation; dry eye; vertigo; atrioventricular block, bradycardia, cardiac failure, cyanosis; necrotising vasculitis, hypotension, Raynaud's phenomenon, increase of an existing intermittent claudication, peripheral coldness
  • Respiratory, gastrointestinal, skin, renal, other (section 4.8): dyspnoea, bronchospasm (generally in patients with pre-existing asthma or obstructive airways disease); retroperitoneal fibrosis; allergic dermatitis, psoriasiform dermatitis, erythematous rash; arthralgia; oliguria, glucosuria (in diabetic and other susceptible patients); erectile dysfunction; fatigue, weakness, thirst; increased blood urea, increased antinuclear antibody
  • Psychiatric and other (section 4.8): hallucination, depression, disorientation, confusional state, nightmare, insomnia; aggravation of pre-existing myopia, visual impairment; acute pancreatitis, dyspepsia, vomiting, nausea, diarrhoea; rash with associated photosensitivity; muscle pain
  • Thiazide diuretics may cause excessive depletion of fluid and electrolytes during prolonged or intense use (muscle pain or fatigue, thirst, oliguria); hypokalaemia is more severe in patients already depleted of potassium, as in renal or hepatic insufficiency (section 4.8)
  • Sulfonamide-type idiosyncratic reaction: choroidal effusion with visual field defect, transient myopia and acute angle-closure glaucoma, typically within hours to weeks of starting (sections 4.4, 4.8)

Interactions

  • Verapamil, disopyramide, lignocaine and tocainide: serious effects reported with beta-blockers; may be anticipated with diltiazem, quinidine, amiodarone and any class 1 antiarrhythmic; special care when given intravenously to patients on beta-blockers (section 4.5)
  • Digitalis glycosides: may increase atrio-ventricular conduction time (section 4.5)
  • Clonidine: beta-blockers increase the risk of rebound hypertension; continue clonidine for some time after the beta-blocker is stopped (section 4.5)
  • Tricyclic antidepressants, barbiturates, phenothiazines, dihydropyridine derivatives such as nifedipine, or other antihypertensive agents: may increase the blood-pressure-lowering effect (section 4.5)
  • Anaesthetics: may attenuate reflex tachycardia and increase the risk of hypotension; inform the anaesthetist; if beta-blockade is interrupted before surgery, stop at least 24 hours beforehand; avoid ether, cyclopropane and trichloroethylene, and avoid local anaesthetics with added vasoconstrictors such as adrenaline (section 4.5)
  • Cimetidine or hydralazine increase, and rifampicin reduces, beta-blocker bioavailability; alcohol increases plasma levels of hepatically metabolised beta-blockers such as timolol (section 4.5)
  • Prostaglandin synthetase inhibiting drugs (NSAIDs) may impair the antihypertensive effect of beta-blockers (section 4.5)
  • Sulfonylureas: beta-blockers could further increase the risk of severe hypoglycaemia (section 4.4)
  • Drugs that increase the QT interval (astemizole, terfenadine, halofantrine, pimozide, sotalol): concomitant use with thiazide diuretics may increase the risk of arrhythmias (section 4.5)
  • Other drugs causing hypokalaemia: increased risk of hypokalaemia with thiazide diuretics (section 4.5; the list that follows in the SPC is cut off at the source-fetch limit, so this interaction list is partial)

Monitoring

  • Observe all patients for evidence of cardiac failure; if it occurs, withdraw the beta-blocker gradually (section 4.4)
  • Pulse rate: if it falls below 50-55 beats per minute at rest and the patient has bradycardia-related symptoms, reduce the dosage (section 4.4)
  • Electrolytes and fluids, especially with high doses, long-term use or in renal impairment (section 4.4)
  • Serum calcium: thiazides may cause intermittent slight elevation; discontinue thiazides before parathyroid function tests (section 4.4)
  • Blood glucose in diabetic patients; beta-blockers may mask the symptoms of thyrotoxicosis or hypoglycaemia (section 4.4)
  • Visual acuity or ocular pain of acute onset (acute angle-closure glaucoma): stop the drug as rapidly as possible (section 4.4)
  • Skin rashes and/or dry eyes: consider discontinuation if not otherwise explicable; stop the beta-blocker gradually (section 4.4)

Clinical monograph

How it works

Timolol reduces cardiac output and renin release through non-selective beta-adrenoceptor blockade, while bendroflumethiazide inhibits the distal tubular sodium-chloride co-transporter to promote natriuresis and lower vascular resistance over time.

Prescribing in practice

  • As a non-selective beta-blocker, the timolol component is contraindicated in asthma and can provoke bronchospasm, and it should not be used in marked bradycardia, high-grade heart block or uncontrolled heart failure.
  • Bendroflumethiazide can cause hypokalaemia, hyponatraemia, hyperuricaemia (precipitating gout) and impaired glucose tolerance, and the beta-blocker may mask the adrenergic warning signs of hypoglycaemia in people with diabetes.
  • Do not stop the beta-blocker abruptly, as rebound effects can occur.

Monitoring

Monitor blood pressure, heart rate, serum electrolytes and renal function at initiation and periodically during treatment.

Counselling the patient

  • Do not stop the tablet suddenly without medical advice.
  • Report wheeze, marked breathlessness, or muscle cramps and weakness.
  • If you have diabetes, be aware that low-glucose warning symptoms may be blunted.

Evidence & guidelines

Beta-blocker plus thiazide combinations are long-established antihypertensives, with NICE positioning beta-blockers and thiazide-like diuretics within stepwise blood-pressure management.

Reference: 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).

Related

Curated clinical cross-links plus same-class fallbacks.

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