Yes: Tablet

Diuretic, Thiazide

Management of mild to moderate hypertension; treatment of edema in congestive heart failure and nephrotic syndrome

B (per manufacturer); D (based on expert analysis)

Hypersensitivity to hydrochlorothiazide or any component, thiazides, or sulfonamide-derived drugs; anuria; renal decompensation; pregnancy

Avoid in severe renal disease (ineffective). Electrolyte disturbances (hypokalemia, hypochloremic alkalosis, hyponatremia) can occur. Use with caution in severe hepatic dysfunction; hepatic encephalopathy can be caused by electrolyte disturbances. Gout can be precipitate in certain patients with a history of gout, a familial predisposition to gout, or chronic renal failure. Cautious use in diabetics; may see a change in glucose control. Hypersensitivity reactions can occur. Can cause SLE exacerbation or activation. Use with caution in patients with moderate or high cholesterol concentrations. Photosensitization may occur. Correct hypokalemia before initiating therapy.

1% to 10%:

Cardiovascular: Orthostatic hypotension, hypotension

Endocrine & metabolic: Hypokalemia

Dermatologic: Photosensitivity

Gastrointestinal: Anorexia, epigastric distress

<1% (Limited to important or life-threatening symptoms): Allergic myocarditis, alopecia, exfoliative dermatitis, toxic epidermal necrolysis, erythema multiforme, Stevens-Johnson syndrome, aplastic anemia, hemolytic anemia, leukopenia, agranulocytosis, thrombocytopenia, hepatic function impairment, renal failure, interstitial nephritis, respiratory distress, allergic reactions (possibly with life-threatening anaphylactic shock), eosinophilic pneumonitis

Symptoms of overdose include hypermotility, diuresis, lethargy, confusion, muscle weakness

Following GI decontamination, therapy is supportive with I.V. fluids, electrolytes, and I.V. pressors if needed

Angiotensin-converting enzyme inhibitors: Increased hypotension if aggressively diuresed with a thiazide diuretic.

Beta-blockers increase hyperglycemic effects in Type 2 diabetes mellitus.

Cyclosporine and thiazides can increase the risk of gout or renal toxicity; avoid concurrent use.

Digoxin toxicity can be exacerbated if a thiazide induces hypokalemia or hypomagnesemia.

Lithium toxicity can occur by reducing renal excretion of lithium; monitor lithium concentration and adjust as needed.

Neuromuscular blocking agents can prolong blockade; monitor serum potassium and neuromuscular status.

NSAIDs can decrease the efficacy of thiazides reducing the diuretic and antihypertensive effects.

Inhibits sodium reabsorption in the distal tubules causing increased excretion of sodium and water as well as potassium and hydrogen ions

Onset of diuretic action: Oral: Within 2 hours

Peak effect: 4 hours

Duration: 6-12 hours

Absorption: Oral: ~60% to 80%

Half-life: 5.6-14.8 hours

Elimination: Excreted unchanged in urine

Oral (effect of drug may be decreased when used every day):

<6 months: 2-3 mg/kg/day in 2 divided doses

>6 months: 2 mg/kg/day in 2 divided doses

Adults: 25-100 mg/day in 1-2 doses

Maximum: 200 mg/day

Elderly: 12.5-25 mg once daily

Minimal increase in response and more electrolyte disturbances are seen with doses >50 mg/day.

Dosing adjustment/comments in renal impairment: Cl_cr 25-50 mL/minute: Not effective

This product may cause a potassium loss; your physician may prescribe a potassium supplement, another medication to help prevent the potassium loss, or recommend that you eat foods high in potassium, especially citrus fruits; do not change your diet on your own while taking this medication, especially if you are taking potassium supplements or medications to reduce potassium loss; too much potassium can be as harmful as too little; may be administered with food

Assess weight, I & O reports daily to determine fluid loss; blood pressure, serum electrolytes, BUN, creatinine

creatine phosphokinase [CPK] (S), ammonia (B), amylase (S), calcium (S), chloride (S), cholesterol (S), glucose, acid (S), chloride (S), magnesium, potassium (S), sodium (S); Tyramine and phentolamine tests, histamine tests for pheochromocytoma

Thiazide diuretics are effective first-line therapeutic agents in the management of hypertension and have proven to be of benefit in terms of cardiovascular outcome. They may act synergistically to lower blood pressure when combined with an ACE inhibitor or beta-blocker. The initial concern about thiazide diuretic-induced hypokalemia, glucose intolerance, and lipid profiles does not appear to be of substantial clinical consequence in the treatment of hypertension. The benefits of this class of agents in the treatment of hypertension is established and compares well with other first-line therapeutic agents.

None reported

Used to treat lithium-induced diabetes insipidus; monitor for hypokalemia; may decrease lithium clearance resulting in an increase in serum lithium levels and potential lithium toxicity; monitor serum lithium levels

No information available to require special precautions

No effects or complications reported

This medication does not replace other antihypertensive recommendations (diet and lifestyle changes). Take as directed, with meals, early in the day to avoid nocturia. Avoid alcohol or OTC medication unless approved by prescriber. Include bananas and/or orange juice in daily diet; do not take potassium supplements unless recommended by prescriber. May cause dizziness or postural hypotension (use caution when rising from sitting or lying position, when driving, climbing stairs, or engaging in tasks that require alertness until response to drug is known); nausea or vomiting (small frequent meals, frequent mouth care, sucking lozenges, or chewing gum may help); impotence (reversible); constipation (increased exercise or dietary fruit, fiber, or fluids will help); photosensitivity (use sunscreen, wear protective clothing and eyewear, and avoid direct sunlight). If diabetic, monitor serum glucose closely; this medication may increase serum glucose levels. Report persistent flu-like symptoms, chest pain, palpitations, muscle cramping, difficulty breathing, skin rash or itching, unusual bruising or easy bleeding, or excessive fatigue. Pregnancy/breast-feeding precautions: Consult prescriber if breast-feeding.

Take blood pressure with patient lying down and standing

Capsule: 12.5 mg

Solution, oral (mint flavor): 50 mg/5 mL (50 mL)

Tablet: 25 mg, 50 mg, 100 mg

Allen JH, McKenney JM, Stratton MA, et al, "Antihypertensive Effect of Hydrochlorothiazide Administered Once or Twice Daily," Clin Pharm, 1982, 1(3):239-43.

Materson BJ, "Diuretic-Associated Hypokalemia," Arch Intern Med, 1985, 145(11):1966-7.

Zahid M, Krumlovsky FA, Roxe D, et al, "Central Nervous System and Cardiac Manifestations of Hydrochlorothiazide Overdosage; Treatment With Hemodialysis," Am J Kidney Dis, 1988, 11(6):508-11.