Chlorthalidone
Nursing pharmacology study reference (NCLEX-style monograph). Numeric values are standard teaching ranges for study and must be verified against current manufacturer labeling before clinical use. This is educational content, not prescribing guidance.
Chlorthalidone — Antihypertensive, diuretic; Thiazide-like diuretic.
Identification
- Therapeutic class: Antihypertensive, diuretic.
- Pharmacologic class: Thiazide-like diuretic.
Pharmacology
- Mechanism of action: Same distal tubule action as thiazides with a longer duration.
- Onset / peak / duration: Onset about 2 hours; peak 2 to 6 hours; duration 24 to 72 hours.
- Half-life / therapeutic level: Half-life 40 to 60 hours; no routine level.
Clinical use
- Indications: Hypertension, edema.
- Usual dose, route, frequency: 12.5 to 25 mg PO once daily.
- Maximum dose / adjustments: Max about 50 mg/day; greater potassium loss than hydrochlorothiazide.
Safety
- Contraindications: Anuria, sulfonamide hypersensitivity.
- Black box warning: None.
- Interactions: Same as hydrochlorothiazide; digoxin, lithium, NSAIDs.
- Pregnancy / lactation: Use only if clearly needed.
- High-alert: No.
Adverse effects
- Common side effects: Hypokalemia, hyponatremia, increased urination, dizziness.
- Serious effects to report: Severe electrolyte disturbance, dehydration.
- Antidote / reversal: None; correct electrolytes.
Nursing process
- Assessment before administration: Blood pressure, electrolytes, renal function.
- Interventions during therapy: Morning dosing; monitor potassium closely.
- Monitor: Electrolytes, blood pressure, glucose, uric acid.
- Evaluation / expected outcome: Sustained blood pressure reduction.
Patient teaching
- Patient teaching: Take in the morning; report cramps or weakness.
- Notify provider if: Muscle weakness, palpitations, severe dizziness.
- Administration tips: Morning dosing.