Bumetanide

bumetanide

(byoo met' a nide)

Bumex, Burinex (CAN)

Pregnancy Category C

Drug class

Loop (high ceiling) diuretic

Therapeutic actions

Inhibits the reabsorption of sodium and chloride from the proximal and distal renal tubules and the loop of Henle, leading to a natriuretic diuresis.

Indications

·        Edema associated with CHF, cirrhosis, renal disease

·        IV: Acute pulmonary edema

·        Unlabeled use: Treatment of adult nocturia (not effective in men with BPH)

Contraindications and cautions

·        Contraindicated with allergy to bumetanide; electrolyte depletion; anuria, severe renal failure; hepatic coma; lactation.

·        Use cautiously with SLE, gout, diabetes mellitus, pregnancy.

Available forms

Tablets—0.5, 1, 2 mg; injection—0.25 mg/mL

Dosages

ADULTS

Oral

0.5–2 mg/day PO in a single dose; may repeat at 4- to 5-hr intervals up to a maximum daily dose of 10 mg. Intermittent dosage schedule of drug and rest days is 3–4 on/1–2 off, which is most effective with edema.

Parenteral

0.5–1 mg IV or IM. Give over 1–2 min. Dose may be repeated at intervals of 2–3 hr. Do not exceed 10 mg/day.

PEDIATRIC PATIENTS

Not recommended for children < 18 yr.

GERIATRIC PATIENTS OR PATIENTS WITH RENAL IMPAIRMENT

A continuous infusion of 12 mg over 12 hr may be more effective and less toxic than intermittent bolus therapy.

Pharmacokinetics

Route	Onset	Peak	Duration
Oral	30–60 min	1–2 hr	4–6 hr
IV	Minutes	15–30 min	30–60 min

Metabolism: T_1/2: 60–90 min

Distribution: Crosses placenta; may enter breast milk

Excretion: Urine

IV facts

Preparation: May be given direct IV or diluted in solution with 5% dextrose in water, 0.9% sodium chloride, or lactated Ringer's solution. Discard unused solution after 24 hr.

Infusion: Give by direct injection slowly, over 1–2 min. Further diluted in solution; give slowly; do not exceed 10 mg/day.

Adverse effects

·        CNS: Asterixis, dizziness, vertigo, paresthesias, confusion, fatigue, nystagmus, weakness, headache, drowsiness, fatigue, blurred vision, tinnitus, irreversible hearing loss

·        CV: Orthostatic hypotension, volume depletion, cardiac arrhythmias, thrombophlebitis

·        GI: Nausea, anorexia, vomiting, diarrhea, gastric irritation and pain, dry mouth, acute pancreatitis, jaundice

·        GU: Polyuria, nocturia, glycosuria, renal failure

·        Hematologic: Hypokalemia, leukopenia, anemia, thrombocytopenia

·        Local: Pain, phlebitis at injection site

·        Other: Muscle cramps and muscle spasms, weakness, arthritic pain, fatigue, hives, photosensitivity, rash, pruritus, sweating, nipple tenderness

Interactions

Drug-drug

·        Decreased diuresis and natriuresis with NSAIDs

·        Increased risk of cardiac glycoside toxicity (secondary to hypokalemia)

·        Increased risk of ototoxicity if taken with aminoglycoside antibiotics, cisplatin

Nursing considerations

Assessment

·        History: Allergy to bumetanide, electrolyte depletion, anuria, severe renal failure, hepatic coma, SLE, gout, diabetes mellitus, lactation

·        Physical: Skin color, lesions; edema; orientation, reflexes, hearing; pulses, baseline ECG, BP, orthostatic BP, perfusion; R, pattern, adventitious sounds; liver evaluation, bowel sounds; urinary output patterns; CBC, serum electrolytes (including calcium), blood sugar, LFTs, renal function tests, uric acid, urinalysis

Interventions

·        Give with food or milk to prevent GI upset.

·        Mark calendars or use reminders if intermittent therapy is best for treating edema.

·        Give single dose early in day so increased urination will not disturb sleep.

·        Avoid IV use if oral use is possible.

·        Arrange to monitor serum electrolytes, hydration, liver function during long-term therapy.

·        Provide diet rich in potassium or supplemental potassium.

Teaching points

·        Record alternate day or intermittent therapy on a calendar or dated envelopes.

·        Take the drug early in day so increased urination will not disturb sleep; take with food or meals to prevent GI upset.

·        Weigh yourself on a regular basis, at the same time, and in the same clothing; record the 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, such as driving; and alcohol consumption); sensitivity to sunlight (use sunglasses, sunscreen, wear protective clothing); increased thirst (suck sugarless lozenges; use frequent mouth care); loss of body potassium (a potassium-rich diet, or supplement will be needed).

·        Report weight change of more than 3 pounds in 1 day; swelling in ankles or fingers; unusual bleeding or bruising; nausea, dizziness, trembling, numbness, fatigue; muscle weakness or cramps.

Adverse effects in Italic are most common; those in Bold are life-threatening.