TENORET Film-coated tablet Ref.[28069] Active ingredients: Atenolol Chlortalidone

Due to its beta-blocker component Tenoret tablets:

• although contraindicated in uncontrolled heart failure (See Section 4.3), may be used in patients whose signs of heart failure have been controlled. Caution must be exercised in patients whose cardiac reserve is poor.
• may increase the number and duration of angina attacks in patients with Prinzmetal’s angina due to unopposed alpha receptor mediated coronary artery vasoconstriction. Atenolol is a beta1-selective beta-blocker; consequently the use of Tenoret tablets may be considered although utmost caution must be exercised.
• although contraindicated in severe peripheral arterial circulatory disturbances (See Section 4.3), may also aggravate less severe peripheral arterial circulatory disturbances.
• due to its negative effect on conduction time, caution must be exercised if it is given to patients with first-degree heart block.
• may modify warning signs of hypoglycaemia as tachycardia, palpitation and sweating.
• may mask the cardiovascular signs of thyrotoxicosis.
• will reduce heart rate, as a result of its pharmacological action. In the rare instances when a treated patient develops symptoms which may be attributable to a slow heart rate, the dose may be reduced.
• should not be discontinued abruptly in patients suffering from ischaemic heart disease.
• may cause a more severe reaction to a variety of allergens, when given to patients with a history of anaphylactic reactions to such allergens. Such patients may be unresponsive to the usual doses of adrenaline used to treat the allergic reactions.
• may cause a hypersensitivity reaction including angioedema and urticaria.
• patients with bronchospastic disease should, in general, not receive beta-blockers due to increasing in airways resistance. Atenolol is a beta1-selective beta-blocker; however this selectivity is not absolute. Therefore the lowest possible dose of Tenoret should be used and utmost caution must be exercised. If increased airways resistance does occur, Tenoret should be discontinued and bronchodilator therapy (e.g. salbutamol) administered if necessary.

The label and patient information leaflet for this product state the following warning: “If you have ever had asthma or wheezing, do not take this medicine without first checking with your doctor”.

• systemic effects of oral beta-blockers may be potentiated when used concomitantly with ophthalmic beta-blockers.
• in patients with phaeochromocytoma must be administered only after alfa-receptor blockade. Blood pressure should be monitored closely.
• caution must be exercised when using anaesthetic agents with Tenoret. The anaesthetist should be informed and the choice of anaesthetic should be an agent with as little negative inotropic activity as possible. Use of beta-blockers with anaesthetic drugs may result in attenuation of the reflex tachycardia and increase the risk of hypotension. Anaesthetic agents causing myocardial depression are best avoided.

Due to its chlortalidone component:

• plasma electrolyte should be periodically determined in appropriate intervals to detect possible electrolyte imbalance especially hypokalaemia and hyponatraemia.
• hypokalaemia and hyponatraemia may occur. Measurement of electrolytes is recommended, especially in the older patient, those receiving digitalis preparations for cardiac failure, those taking an abnormal (low in potassium) diet or those suffering from gastrointestinal complaints. Hypokalaemia may predispose to arrhythmias in patients receiving digitalis.
• impaired glucose tolerance may occur and diabetic patients should be aware of the potential for increased glucose levels. Close monitoring of glycaemia is recommended in the initial phase of therapy and in prolonged therapy test for glucosuria should be carried out at regular intervals.
• in patients with impaired hepatic function or progressive liver disease, minor alterations in fluid and electrolyte balance may precipitate hepatic coma.
• hyperuricaemia may occur. Only a minor increase in serum uric acid usually occurs but in cases of prolonged elevation, the concurrent use of a uricosuric agent will reverse the hyperuricaemia.

Choroidal effusion, acute myopia and secondary angle-closure glaucoma:

Sulfonamide or sulfonamide derivative drugs can cause an idiosyncratic reaction resulting in choroidal effusion with visual field defect, transient myopia and acute angle-closure glaucoma. Symptoms include acute onset of decreased visual acuity or ocular pain and typically occur within hours to weeks of drug initiation. Untreated acute angle-closure glaucoma can lead to permanent vision loss. The primary treatment is to discontinue drug intake as rapidly as possible. Prompt medical or surgical treatments may need to be considered if the intraocular pressure remains uncontrolled. Risk factors for developing acute angle-closure glaucoma may include a history of sulfonamide or penicillin allergy.

Sodium Content

This medicine contains less than 1 mmol sodium (23 mg) per tablet, that it is to say essentially ‘sodium-free’.

Due to atenolol

Combined use of beta-blockers and calcium channel blockers with negative inotropic effects, e.g. verapamil, diltiazem, can lead to an exaggeration of these effects particularly in patients with impaired ventricular function and/or sino-atrial or atrio-ventricular conduction abnormalities. This may result in severe hypotension, bradycardia and cardiac failure. Neither the beta-blocker nor the calcium channel blocker should be administered intravenously within 48 hours of discontinuing the other.

Class I anti-arrhythmic drugs (e.g. disopyramide) and amiodarone may have a potentiating effect on atrial-conduction time and induce negative inotropic effect.

Digitalis glycosides, in association with beta-blockers, may increase atrio-ventricular conduction time.

Beta-blockers may exacerbate the rebound hypertension which can follow the withdrawal of clonidine. If the two drugs are co-administered, the beta-blocker should be withdrawn several days before discontinuing clonidine. If replacing clonidine by beta-blocker therapy, the introduction of -blockers should be delayed for several days after clonidine administration has stopped.

Concomitant use of sympathomimetic agents, e.g. adrenaline (epinephrine), may counteract the effect of beta-blockers.

Concomitant use of prostaglandin synthetase-inhibiting drugs e.g. ibuprofen and indometacin, may decrease the hypotensive effects of beta-blockers.

Caution must be exercised when using anaesthetic agents with Tenoret tablets (see section 4.4).

Due to chlortalidone

The chlortalidone component may reduce the renal clearance of lithium leading to increased serum concentrations. Dose adjustments of lithium may therefore be necessary.

Concomitant use with insulin and oral antidiabetic drugs may lead to the intensification of the blood sugar lowering effects of these drugs.

Due to the combination product

Concomitant therapy with dihydropyridines e.g. nifedipine, may increase the risk of hypotension, and cardiac failure may occur in patients with latent cardiac insufficiency.

Concomitant use of baclofen may increase the antihypertensive effect making dose adjustments necessary.

Fertility

No data on fertility available.

Pregnancy

Tenoret tablets must not be given during pregnancy.

Lactation

Tenoret tablets must not be given during lactation.

Use is unlikely to result in any impairment of the ability of patients to drive or use machinery. However, it should be taken into account that occasionally dizziness or fatigue may occur.

Tabulated list of adverse reactions

Tenoret tablets were well tolerated in clinical studies, the undesired events reported are usually attributable to the pharmacological actions of its components.

The following undesired events, listed by body system, have been reported with the following frequencies: very common (≥1/10); common (≥1/100 to <1/10); uncommon (≥1/1,000 to <1/100); rare ((≥1/10,000 to <1/1,000); very rare (<1/10,000); not known (cannot be estimated from the available data).

Cases of choroidal effusion with visual field defect have been reported after the use of thiazide and thiazide-like diuretics.

Discontinuance of Tenoret tablets should be considered if, according to clinical judgement, the well-being of the patient is adversely affected by any of the above reactions.

Reporting of suspected adverse reactions

Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme. Website: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.

Not applicable.