Generic Name

Hydrochlorothiazide; Valsartan

---

Classification

FDA Approved Indications

• Hypertension
• Heart failure (additional indication for Valsartan alone)

Mechanism of Action

Valsartan blocks the angiotensin II receptor, leading to vasodilation and decreased aldosterone effects; Hydrochlorothiazide promotes diuresis by inhibiting sodium reabsorption in the distal tubules of the nephron, reducing blood volume and pressure.

Dosage and Administration

Adult: Typically, 1 tablet once daily, dosage adjusted based on response and clinical condition.

Pediatric: Not generally recommended for children.

Geriatric: Use with caution; monitor renal function and electrolytes.

Renal Impairment: Adjust dose or avoid in severe impairment; monitor renal function closely.

Hepatic Impairment: Use with caution; no specific dose adjustment outlined.

Pharmacokinetics

Absorption: Well absorbed orally

Distribution: Valsartan is approximately 10-20% protein-bound; Hydrochlorothiazide is 40-80% protein-bound

Metabolism: Valsartan undergoes minimal hepatic metabolism; Hydrochlorothiazide undergoes negligible metabolism

Excretion: Renal excretion for both components

Half Life: Valsartan approximately 6-9 hours; Hydrochlorothiazide approximately 6 hours

Contraindications

• Hypersensitivity to sulfonamides or components
• Bilateral renal artery stenosis
• Anuria

Precautions

• Pregnancy (category D, see pregnancy section)
• Electrolyte imbalances
• Impaired renal or hepatic function
• History of angioedema

Adverse Reactions - Common

• Hypotension (Common)
• Dizziness (Common)
• Hypokalemia (Common)
• Hyperkalemia (Common)

Adverse Reactions - Serious

• Angioedema (Rare)
• Acute renal failure (Rare)
• Severe hypersensitivity reactions (Rare)

Drug-Drug Interactions

• Other antihypertensives
• Potassium-sparing diuretics
• NSAIDs
• Lithium

Drug-Food Interactions

• Potassium-rich foods (can increase risk of hyperkalemia)

Drug-Herb Interactions

• St. John's Wort (may reduce efficacy)

Nursing Implications

Patient/Family Teaching

• Take medication exactly as prescribed, even if feeling well
• Monitor for signs of electrolyte imbalance: muscle weakness, cramps, irregular heartbeat
• Report signs of swelling, difficulty breathing immediately
• Limit potassium-rich foods if instructed

Special Considerations

Black Box Warnings:

• Fetal toxicity—discontinue as soon as pregnancy is detected

Genetic Factors: Limited data; no specific genetic considerations noted

Lab Test Interference: May affect serum electrolyte measurements

Overdose Management

Signs/Symptoms: Severe hypotension, electrolyte disturbances, dehydration

Treatment: Discontinue medication; supportive care, vasopressors if needed; correct electrolytes

Storage and Handling

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

Stability: Stable under recommended conditions; check expiration date