Generic Name

Atenolol + Chlorthalidone

Precaution

Bronchospastic disease, renal or hepatic impairment, elderly. May aggravate peripheral arterial circulatory disorder. Beta-blocker can depress myocardial contractility; continued use in patients without history of cardiac failure may in some cases, lead to cardiac failure. Caution in patients receiving anaesthetic agents that may depress myocardium. In patients with coronary artery disease, abrupt withdrawal may cause angina pectoris exacerbation, MI. Atenolol may mask signs (tachycardia) of hypoglycaemia and thyrotoxicosis. Latent DM may manifest with Chlorthalidone therapy. Chlorthalidone can cause hyperuricaemia and precipitate gout. Monitor renal functions, potassium levels, and signs of fluid and electrolytes imbalance. Discontinue if progressive renal impairment is evident. Not recommended in pregnancy and lactation. Safety and efficacy in paediatric patients have not been established. Lactation: excreted in breast milk, use caution

Indication

Hypertension

Contra Indication

Sinus bradycardia, 2nd or 3rd degree heart block, cardiogenic shock, anuria, hypersentivity to either product or sulphonamide derivatives.

Dose

N/A

Side Effect

Atenolol: Dyspnoea, wheeziness, bradycardia, hypotension, cold extremities, fatigue, dizziness, insomnia, lethargy, confusion, headache, depression, nightmares, nausea, diarrhoea, constipation, impotence, paraesthesia, rash, Raynaud's phenomenon. Chlorthalidone: Orthostatic hypotension, GI disturbances, jaundice, pancreatitis, vertigo, lethargy, paraesthesia, photosensitivity, rash, muscle cramps, hypokalaemia, hyponatraemia, hyperglycaemia, hyperuricaemia or gout, leucopenia, agranulocytosis, aplastic anaemia, thrombocytopenia. Potentially Fatal: Atenolol: Heart failure, 2nd or 3rd degree AV block. Chlorthalidone: Hypersensitivity reaction including toxic epidermal necrolysis.

Pregnancy Category

Mode of Action

Atenolol is a beta-blocker that acts preferentially on the ?1 adrenergic receptors in the heart. Chlorthalidone is a thiazide-like diuretic that reduces BP possibly by inhibiting sodium reabsorption at the beginning of the distal convulated tubule. Combination of the two drugs results in additive antihypertensive action.

Interaction

Concomitant admin w/ reserpine may increase hypotension and bradycardia. Additive w/ Ca channel blockers, hydralazine, methyldopa. Increased risk of bradycardia and heart block w/ verapamil and diltiazem. May decrease hypotensive effects w/ NSAIDs (e.g. indometacin). Enhanced bradycardic effect w/ disopyramide, amiodarone or digitalis glycosides. May exacerbate rebound HTN upon discontinuance of clonidine treatment.

Pregnancy Category Note

Pregnancy Category: D Lactation: excreted in breast milk, use caution

Adult Dose

Adult: Per tab contains Atenolol (mg)/Chlorthalidone (mg): 50/25 or 100/25. Initially one tab of 50/25 once daily; may increase to one tab of 100/25 based on response.

Child Dose

N/A

Renal Dose

Renal impairment: CrCl (ml/min) 15-35 Max dose of Atenolol component: 50 mg/day <15 Max dose of Atenolol component: 50 mg every other day.

Administration

N/A