Fosinopril Sodium

fosinopril sodium (foh sin' oh pril) Monopril Pregnancy Category C (first trimester) Pregnancy Category D (second and third trimesters) Drug classes

Antihypertensive Angiotensin-converting enzyme (ACE) inhibitor Therapeutic actions

Renin, synthesized by the kidneys, is released into the circulation where it acts on a plasma precursor to produce angiotensin I, which is converted by angiotensin-converting enzyme to angiotensin II, a potent vasoconstrictor that also causes release of aldosterone from the adrenals; fosinopril blocks the conversion of angiotensin I to angiotensin II, leading to decreased BP, decreased aldosterone secretion, a small increase in serum potassium levels, and sodium and fluid loss; increased prostaglandin synthesis may be involved in the antihypertensive action. Indications

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Treatment of hypertension, alone or in combination with thiazide-type diuretics Management of CHF as adjunctive therapy Unlabeled use: Diabetic nephropathy

Contraindications and cautions

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Contraindicated with allergy to fosinopril or other ACE inhibitors; pregnancy. Use cautiously with impaired renal function, hyperkalemia, salt or volume depletion, lactation.

Available forms

Tablets—10, 20, 40 mg Dosages ADULTS

Initial dose, 10 mg PO daily. Maintenance dose, 20–40 mg/day PO as a single dose or 2 divided doses. In patients receiving diuretic therapy, begin fosinopril therapy with 10 mg. Do not exceed maximum dose of 80 mg. PEDIATRIC PATIENTS

Safety and efficacy not established. Pharmacokinetics Route Oral

Onset 1 hr

Peak 3 hr

Duration 24 hr

Metabolism: Hepatic; T1/2: 12 hr Distribution: Crosses placenta; enters breast milk Excretion: Urine and feces

Adverse effects

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CV: Angina pectoris, orthostatic hypotension in salt- or volume-depleted patients, palpitations Dermatologic: Rash, pruritus, diaphoresis, flushing GI: Nausea, abdominal pain, vomiting, diarrhea Respiratory: Cough, asthma, bronchitis, dyspnea, sinusitis Other: Angioedema, asthenia, myalgia, arthralgia, hyperkalemia

Interactions

Drug-drug • Decreased effectiveness if combined with indomethacin or other NSAIDs • Risk of lithium toxicity if combined with ACE inhibitors • Risk of increased potassium levels if taken with potassium-sparing diuretics • Decreased absorption when given with antacids; separate by at least 2 hr. Nursing considerations CLINICAL ALERT!

Name confusion has occurred between fosinopril and lisinopril; use caution. Assessment

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History: Allergy to fosinopril and other ACE inhibitors, impaired renal or hepatic function, hyperkalemia, salt or volume depletion, lactation, pregnancy Physical: Skin color, lesions, turgor; T; P, BP, peripheral perfusion; mucous membranes, bowel sounds, liver evaluation; urinalysis, renal and liver function tests, CBC, and differential

Interventions

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Alert surgeon and mark patient's chart with notice that fosinopril is being taken; the angiotensin II formation subsequent to compensatory renin release during surgery will be blocked; hypotension may be reversed with volume expansion. Arrange to switch to a different drug if pregnancy occurs; suggest using barrier contraceptives. Monitor patient closely for a fall in BP secondary to reduction in fluid volume (excessive perspiration and dehydration, vomiting, diarrhea) because excessive hypotension may occur.

Teaching points

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Do not stop taking the medication without consulting your prescriber. Avoid pregnancy while taking this drug; using barrier contraceptives is advised. Be careful in any situation that may lead to a drop in BP (diarrhea, sweating, vomiting, dehydration); if light-headedness or dizziness occurs, consult your care provider.

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These side effects may occur: GI upset, loss of appetite (these may be transient); light-headedness (transient; change position slowly and limit activities to those that do not require alertness and precision); dry cough (not harmful). Report mouth sores; sore throat, fever, chills; swelling of the hands, feet; irregular heartbeat, chest pains; swelling of the face, eyes, lips, tongue, difficulty breathing, persistent cough.

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