Hydrochlorothiazide
Generic Details
Generic Name
Hydrochlorothiazide
Other Names
- HCTZ
Drug Class
- Diuretic
- Thiazide Diuretic
Chemical Formula
C7H8ClN3O4S2
Molecular Weight
297.73 g/mol
Mechanism of Action
- Inhibits the reabsorption of sodium and chloride in the distal convoluted tubule of the nephron.
Indications
- Hypertension
- Edema
- Adjunct in the management of Congestive Heart Failure
Common Dosage Forms
- Tablet
- Capsule
Typical Dosage
- 25-100 mg daily as a single dose or divided doses
Pediatric Dosage
- Dosage varies based on weight and condition, consult a pediatrician
Geriatric Dosage
- Lower doses may be required due to decreased renal function in the elderly
Side Effects
- Electrolyte imbalance (hypokalemia, hyponatremia)
- Dehydration
- Hypotension
- Dizziness
- Headache
Contraindications
- Anuria
- Hypersensitivity to sulfonamides
- Severe renal impairment
Pregnancy Category
- Category B - Animal reproduction studies have failed to demonstrate a risk to the fetus
Lactation Safety
- Compatible with breastfeeding; monitor infant for electrolyte disturbances
Drug Interactions
- Lithium (increased lithium levels)
- NSAIDs (reduced diuretic and antihypertensive effects)
Overdose Symptoms
- Severe dizziness
- Weakness
- Electrolyte abnormalities
Antidote for Overdose
- Symptomatic and supportive treatment; may require electrolyte correction
Storage Conditions
- Store at room temperature away from moisture and heat
Pharmacokinetics
- Absorption: Rapidly absorbed from the gastrointestinal tract
- Distribution: Crosses the placenta, excreted in breast milk
- Metabolism: Metabolized in the liver
- Excretion: Excreted unchanged in the urine
Precautions
- Monitor electrolytes regularly, especially potassium levels
- Caution in patients with renal impairment
Warnings
- May cause photosensitivity
- Avoid sudden changes in position to prevent orthostatic hypotension
Others
- Hydrochlorothiazide may interact with certain diabetes medications, leading to increased blood sugar levels.