Twincard 50/25

• Hypertension (high blood pressure) - to lower blood pressure and reduce cardiovascular event risk

Atenolol is a beta1-selective (cardioselective) beta-adrenergic receptor blocking agent that provides reduction in resting and exercise heart rates and cardiac output, reduction of systolic and diastolic blood pressure, and reduction in reflex orthostatic tachycardia.

Chlorthalidone is a monosulfonamyl diuretic with prolonged action and low toxicity. It produces diuresis with greatly increased excretion of sodium and chloride at the distal convoluted tubule of the nephron.

Combination of the two drugs results in additive antihypertensive action.

Initial Dose: Atenolol 50 mg + Chlorthalidone 25 mg once daily.

Dose Adjustment: Additional antihypertensive agents may be added gradually (starting at 50% of usual dose) if optimal response is not achieved.

Renal Dose: Dose adjustment needed in severe renal impairment (atenolol is renally excreted).

Elderly: Insufficient data for patients ≥65 years; use with caution.

• Nausea
• Diarrhea
• Headache
• Fatigue
• Dizziness
• Cold extremities
• Bradycardia
• Postural hypotension
• Increased blood uric acid
• Hypokalemia
• Hyponatremia
• Hypomagnesemia
• Hypercalcemia
• Glucose intolerance
• Increased blood lipids
• Anorexia
• Gastric irritation
• Vomiting
• Constipation
• Dyspnea

[CONSULT YOUR DOCTOR] Atenolol + Chlorthalidone is unsafe during pregnancy (Category D). There is definite evidence of risk to the developing baby. Use only if potential benefit justifies the risk.

Serious Precautions:

• Do not stop suddenly - may cause rebound hypertension, increasing risk of heart attack and stroke
• Caution in diabetic patients - beta-blockers may mask hypoglycemia symptoms; chlorthalidone may cause glucose intolerance
• May aggravate peripheral arterial circulatory disorders
• Gout risk - chlorthalidone may cause hyperuricemia
• Dehydration risk - drink plenty of fluids; report extreme thirst, muscle weakness, or dry mouth
• Monitor serum electrolytes regularly - risk of electrolyte imbalance
• Monitor renal function - discontinue if progressive renal impairment develops
• Pregnancy Category D - risk to fetus in third trimester
• Caution during breastfeeding - excreted in breast milk

No specific information on overdose in humans. Treatment: symptomatic and supportive, removal of unabsorbed drug (induced emesis or activated charcoal). Atenolol can be removed by hemodialysis. Manage dehydration, electrolyte imbalance, and hypotension.

Store in a cool and dry place, protected from light.