What is the initial medication for a 55-year-old female with hypertension?

Initial Medication for a 55-Year-Old Female with Hypertension

For a 55-year-old female with hypertension, a calcium channel blocker (CCB) or thiazide diuretic is recommended as the initial medication of choice.

Medication Selection Based on Age and Demographics

The selection of initial antihypertensive medication should follow evidence-based guidelines that consider the patient's age, race, and comorbidities:

• For patients ≥55 years old, guidelines from multiple organizations recommend either a calcium channel blocker (CCB) or a thiazide/thiazide-like diuretic as first-line therapy 1
• The British Hypertension Society guidelines specifically recommend that patients 55 years or older should be commenced on either C (calcium channel blockers) or D (diuretics) 1
• The NICE guidelines suggest a CCB for patients ≥55 years of age 1
• The ASH/ISH guidelines similarly recommend the use of a CCB or thiazide for patients aged >60 years 1

Specific Medication Recommendations

Thiazide Diuretic Option

• Chlorthalidone is preferred over hydrochlorothiazide due to:
  • Superior 24-hour blood pressure control 2
  • More extensive evidence in cardiovascular outcome trials 3
  • Better nighttime blood pressure reduction (13.5 mmHg vs 6.4 mmHg) 2
  • Initial dose: 12.5 mg daily, which can be titrated to 25 mg if needed 2

Calcium Channel Blocker Option

• Amlodipine is a commonly recommended CCB:
  • Well-tolerated in older patients
  • Once-daily dosing improves adherence
  • Effective blood pressure reduction

Treatment Algorithm

1. Initial therapy: Start with either:

   • Calcium channel blocker (e.g., amlodipine 5 mg daily) OR
   • Thiazide-like diuretic (e.g., chlorthalidone 12.5 mg daily)

2. Monitoring: Check blood pressure within 2-4 weeks of starting therapy 1

3. Dose adjustment: If blood pressure is not controlled:

   • Increase dose of initial medication, OR
   • Add a second agent from a different class

4. Combination therapy: If needed, the preferred combinations include:

   • CCB + ACE inhibitor/ARB
   • Thiazide diuretic + ACE inhibitor/ARB 1, 4

Important Considerations

• Target blood pressure: <130/80 mmHg for optimal cardiovascular risk reduction 1, 4
• Avoid beta-blockers as initial therapy unless specific indications exist (e.g., coronary artery disease) 4
• Lifestyle modifications should be implemented concurrently:
  • DASH or Mediterranean diet
  • Sodium restriction (<2,300 mg/day)
  • Regular physical activity (150 minutes/week)
  • Weight management if applicable
  • Alcohol moderation 1, 4

Monitoring and Follow-up

• Monitor serum potassium, creatinine, and electrolytes within 2-4 weeks of starting therapy, particularly with diuretics 1, 4
• Schedule follow-up visits every 2-4 weeks until blood pressure is controlled, then every 3-6 months 1, 4
• Watch for potential adverse effects:
  • With CCBs: peripheral edema, headache, flushing
  • With thiazides: hypokalemia, hyperglycemia, hyperuricemia 5

By following these evidence-based recommendations, optimal blood pressure control can be achieved to reduce cardiovascular morbidity and mortality in this 55-year-old female patient with hypertension.