Drug Interaction:
Both carboxolone may increase BP due to fluid retention but there may be an additive effect of chlorthalidone.
Atenolol+
Pseudoephidrine/xylometazoline-
Reduced hypotensive effect with pseudoephidrine /xylometazoline
Amisulphide/alprostadil/flecanide-
Increasec risk of bardycardia with amisulphide, alprostadil, flecainide
Bactofen-
Increase risk of hypotension with baclofen
Sulphonylureas-
Reduced effect of sulphonylureas
Chlorthalidone-
May alter insulin requirements and impair diabetic control in diabetics using oral diabetic medicine
Lithium-
May reduce renal claearance of lithium toxicity.
Digitalis-
May enhance digitalis toxicity
Adverse Reaction:
Atenolol
Bradycardia, heart failure deterioration
Precipitation of heart block, internittant caldication
Reynaud syndrome
Confusion, dizziness, headache, mood changes, nightmares
Dry mouth, GI disturbances
Chlorthalidone- May cause hypersentivity rractions and rarely hyponatraemia
Diabetes and gout may be precipitated
Gastric irritation, vomiting, constipation
Cholestatic jaundice
Atenolol- Heart failure 2nd or 3rd degree AV block
Contra-Indications:
Hypersensitivity
Sinus bradycardia, 2nd or 3rd degree heart block
Cardiogenic shock
Hyptension, severe peripheral arterial circulatory disturbances
Sick sinus syndrome
Untreated phaeochromocytoma, uncontrolled heart failure
Hypersenstivity to either products or sulphonamide derivative
Pregnancy
Special precautions
Caution patients with history of heart failure, poor cardiac resrve 1st degree block or anaphylactic reactions to allergens
Renal or herpatic impairment
Elcetrolyte disturbances
History of bronchospasm. May mask tachycardia as a symptom of hypoglycemia
May mask symptoms of throtoxocosis
May increase frequency and duration of angina attacks in patients with Prinzmetal angina
Aviod abrupt withdrawal in patients with hyperthyroidism may precipitate thyroid storm.
Patients with pre-disposition to DM
Chlorthalidone- May precipitate acute gout in some patients
Lactation Avoid in patients ith reversible obstructive airways disease
Monitor serum K levels esp. in elderly patients receiving digitalis prepn. for cardiac failure, patients on low K diet or patients suffering from GI complaints
Patients with known pre-diposition to DM
Dosages/ Overdosage Etc:
Indication-
Hypertension
Dosage-
Atenolol/ chlorthalidone 50/ 12.5mg or 100/25mg
Take 1 tablet once daily
Pregnancy and lactation:
Contraindicated for use during pregnancy and lactation
Use with caution