Home Drug Guide Chlorthalidone

Drug Guide

Generic Name

Chlorthalidone

Brand Names Hygroton, Thalitone, Hemiclor

Classification

Therapeutic: Antihypertensive; Diuretic

Pharmacological: Thiazide-like diuretic

FDA Approved Indications

  • Hypertension
  • Edema associated with congestive heart failure, renal impairment, or hepatic cirrhosis

Mechanism of Action

Chlorthalidone inhibits sodium reabsorption in the distal tubules of the nephron, increasing the excretion of sodium, chloride, potassium, and water, leading to decreased blood volume and blood pressure.

Dosage and Administration

Adult: Initially, 12.5 to 25 mg once daily. Dosage may be adjusted based on response, up to 50 mg daily.

Pediatric: Not commonly used in pediatric practice; consult specific guidelines.

Geriatric: Start with lower doses due to increased sensitivity; monitor closely.

Renal Impairment: Adjust dose based on renal function; use cautiously.

Hepatic Impairment: Use with caution; dose adjustments may be necessary.

Pharmacokinetics

Absorption: Well absorbed from gastrointestinal tract

Distribution: Widely distributed in body tissues and fluids

Metabolism: Minimal hepatic metabolism

Excretion: Primarily renal excretion of unchanged drug and metabolites

Half Life: about 40-60 hours, allowing once-daily dosing

Contraindications

  • Hypersensitivity to chlorthalidone or sulfonamides
  • Anuria
  • Electrolyte imbalance

Precautions

  • Electrolyte disturbances (hypokalemia, hyponatremia), gout, diabetes mellitus, systemic lupus erythematosus, monitor blood pressure and laboratory parameters regularly. Pregnancy category D; use only if benefits outweigh risks.

Adverse Reactions - Common

  • Electrolyte disturbances (hypokalemia, hyponatremia) (Common)
  • Hypotension (Common)
  • Dizziness (Common)

Adverse Reactions - Serious

  • Electrolyte imbalance leading to arrhythmias (Serious)
  • Hypersensitivity reactions (Serious)
  • Pancreatitis, blood dyscrasias (Rare/Serious)

Drug-Drug Interactions

  • NSAIDs may reduce diuretic and antihypertensive effects, Lithium levels increase, Other antihypertensives may have additive effects

Drug-Food Interactions

  • Alcohol may enhance hypotensive effects

Drug-Herb Interactions

N/A

Nursing Implications

Assessment: Monitor blood pressure, serum electrolytes, kidney function, fluid status.

Diagnoses:

  • Risk for electrolyte imbalance
  • Risk for hypotension

Implementation: Administer in the morning to minimize nocturia. Educate patients on dietary potassium intake.

Evaluation: Assess blood pressure, serum electrolytes, and signs of fluid depletion. Adjust dose as needed.

Patient/Family Teaching

  • Take medication exactly as prescribed.
  • Monitor for signs of electrolyte imbalance (muscle weakness, cramps), dehydration, dizziness.
  • Report rapid heartbeat, confusion, or severe weakness.
  • Maintain adequate potassium intake unless contraindicated.

Special Considerations

Black Box Warnings:

  • None specific to chlorthalidone

Genetic Factors: Some populations (e.g., African Americans) may respond differently—monitor efficacy and side effects.

Lab Test Interference: May cause alterations in serum electrolyte and glucose levels.

Overdose Management

Signs/Symptoms: Severe hypotension, electrolyte disturbances, dehydration

Treatment: Discontinue drug, provide supportive care, correct electrolyte imbalances, and monitor vital signs.

Storage and Handling

Storage: Store at room temperature, away from moisture and light.

Stability: Stable under normal conditions for shelf life specified by manufacturer.

🛡️ 5 Critical Medication Safety Tips for Nurses

1

Triple-Check High-Risk Medications

Always have another nurse verify insulin, heparin, warfarin, and chemotherapy drugs. These "high-alert" medications cause the most serious errors. Check concentration, dose calculation, and pump settings twice.

2

Know Look-Alike, Sound-Alike Drugs

Common mix-ups: hydromorphone/morphine, Celebrex/Celexa, Zyprexa/Zyrtec. Always use BOTH generic and brand names, read labels twice, and use barcode scanning when available. One wrong letter can be fatal.

3

Assess Before AND After Giving Meds

Check vitals before cardiac meds, pain levels before analgesics, and blood glucose before insulin. Always reassess within 30 minutes to evaluate effectiveness and watch for adverse reactions.

4

Watch for Drug Interactions

Common dangerous combinations: warfarin + aspirin (bleeding), ACE inhibitors + potassium (hyperkalemia), digoxin + diuretics (toxicity). Always check drug interactions before administering new medications.

5

Educate Your Patients

Teach patients medication names, purposes, major side effects, and what to report. Informed patients catch errors and improve compliance. Always encourage questions - an educated patient is a safer patient.

⚡ Remember: When in doubt, don't give it out! It's always safer to double-check than regret later.

⚠️ Medical Disclaimer

This drug guide is for educational purposes only and is NOT intended for clinical use. Always consult current prescribing information, healthcare providers, and institutional protocols before administering any medication. Do not use this information for patient care decisions.