(hye droe klor oh thye' a zide)
Apo-Hydro (CAN), Esidrix, Ezide, HydroDIURIL, Microzide Capsules, Novo-Hydrazide (CAN), Oretic, Urozide (CAN)
Pregnancy Category B
Inhibits reabsorption of sodium and chloride in distal renal tubule, increasing the excretion of sodium, chloride, and water by the kidney.
· Adjunctive therapy in edema associated with CHF, cirrhosis, corticosteroid, and estrogen therapy; renal dysfunction
· Hypertension as sole therapy or in combination with other antihypertensives
· Unlabeled uses: Calcium nephrolithiasis alone or with amiloride or allopurinol to prevent recurrences in hypercalciuric or normal calciuric patients; diabetes insipidus, especially nephrogenic diabetes insipidus; osteoporosis
Contraindications and cautions
· Contraindicated with allergy to thiazides, sulfonamides; fluid or electrolyte imbalance; renal disease (can lead to azotemia); liver disease (risk of hepatic coma); anuria.
· Use cautiously with gout (risk of attack); SLE; glucose tolerance abnormalities, diabetes mellitus; hyperparathyroidism; manic-depressive disorder (aggravated by hypercalcemia); pregnancy; lactation, elevated triglyceride levels.
Tablets—25, 50, 100 mg; solution—50 mg/5 mL; capsules—12.5 mg
· Edema: 25–200 mg daily PO until dry weight is attained. Then, 25–100 mg daily PO or intermittently, up to 200 mg/day.
· Hypertension: Starting dose, 12.5–50 mg PO.
· Calcium nephrolithiasis: 50 mg daily or bid PO.
General guidelines: 2.2 mg/kg/day PO in 2 doses.
< 6 mo: Up to 3.3 mg/kg/day in 2 doses.
6 mo–2 yr: 12.5–37.5 mg/day in 2 doses.
2–12 yr: 37.5–100.0 mg/day in 2 doses.
Metabolism: Hepatic; T1/2: 5.6–14.8 hr
Distribution: Crosses placenta; enters breast milk
· CNS: Dizziness, vertigo, paresthesias, weakness, headache, drowsiness, fatigue, leukopenia, thrombocytopenia, agranulocytosis, aplastic anemia, neutropenia
· CV: Orthostatic hypotension, venous thrombosis, volume depletion, cardiac arrhythmias, chest pain
· Dermatologic: Photosensitivity, rash, purpura, exfoliative dermatitis, hives, alopecia
· GI: Nausea, anorexia, vomiting, dry mouth, diarrhea, constipation, jaundice, hepatitis, pancreatitis
· GU: Polyuria, nocturia, impotence, loss of libido
· Other: Muscle cramps and muscle spasms, fever, gouty attacks, flushing, weight loss, rhinorrhea
· Altered electrolytes with loop diueretics, amphotericin B, corticosteroids
· Increased neuromuscular blocking effects and respiratory depression with nondepolarizing muscle relaxants
· Decreased absorption with cholestyramine, colestipol
· Increased risk of cardiac glycoside toxicity if hypokalemia occurs
· Increased risk of lithium toxicity
· Decreased effectiveness of antidiabetic agents
· Decreased PBI levels without clinical signs of thyroid disturbance
· History: Allergy to thiazides, sulfonamides; fluid or electrolyte imbalance; renal or liver disease; gout; SLE; glucose tolerance abnormalities, diabetes mellitus; hyperparathyroidism; manic-depressive disorders; lactation, pregnancy
· Physical: Skin color, lesions, edema; orientation, reflexes, muscle strength; pulses, baseline ECG, BP, orthostatic BP, perfusion; R, pattern, adventitious sounds; liver evaluation, bowel sounds, urinary output patterns; CBC, serum electrolytes, blood glucose, liver and renal function tests, serum uric acid, urinalysis
· Give with food or milk if GI upset occurs.
· Mark calendars or provide other reminders of drug for alternate day or 3–5 days/wk therapy.
· Reduce dosage of other antihypertensives by at least 50% if given with thiazides; readjust dosages gradually as BP responds.
· Administer early in the day so increased urination will not disturb sleep.
· Measure and record weights to monitor fluid changes.
· Record intermittent therapy on a calendar, or use prepared, dated envelopes. Take drug early so increased urination will not disturb sleep. Drug may be taken with food or meals if GI upset occurs.
· Weigh yourself on a regular basis, at the same time and in the same clothing; record weight on your calendar.
· You may experience these side effects: Increased volume and frequency of urination; dizziness, feeling faint on arising, drowsiness (avoid rapid position changes; hazardous activities, like driving; and alcohol); sensitivity to sunlight (use sunglasses, wear protective clothing, or use a sunscreen); decrease in sexual function; increased thirst (sucking on sugarless lozenges and frequent mouth care may help).
· Report weight change of more than 3 lb in 1 day, swelling in your ankles or fingers, unusual bleeding or bruising, dizziness, trembling, numbness, fatigue, muscle weakness or cramps.
Adverse effects in Italic are most common; those in Bold are life-threatening.