Benazepril hydrochloride

benazepril hydrochloride

(ben a' za pril)

Lotensin

Pregnancy Category C (first trimester)

Pregnancy Category D (second, third trimesters)

Drug classes

Antihypertensive

ACE inhibitor

Therapeutic actions

Blocks ACE from converting angiotensin I to angiotensin II, a potent vasoconstrictor, leading to decreased BP, decreased aldosterone secretion, a small increase in serum potassium levels, and sodium and fluid loss; increased prostaglandin synthesis also may be involved in the antihypertensive action.

Indications

·        Treatment of hypertension alone or in combination with thiazide-type diuretics

Contraindications and cautions

·        Contraindicated with allergy to benazepril or other ACE inhibitors, second or third trimester of pregnancy.

·        Use cautiously with impaired renal function, immunosuppresion, CHF, hypotension, salt or volume depletion, lactation, first trimester of pregnancy.

Available forms

Tablets—5, 10, 20, 40 mg

Dosages

ADULTS

Initial dose, 10 mg PO daily. Maintenance dose, 20–40 mg/day PO, single or two divided doses. Patients using diuretics should discontinue them 2–3 d prior to benazepril therapy. If BP is not controlled, add diuretic slowly. If diuretic cannot be discontinued, begin benazepril therapy with 5 mg. Maximum dose, 80 mg.

PEDIATRIC PATIENTS

Safety and efficacy not established.

PATIENTS WITH RENAL IMPAIRMENT

For creatinine clearance < 30 mL/min (serum creatinine > 3 mg/dL), 5 mg PO daily. Dosage may be gradually increased until BP is controlled, up to a maximum of 40 mg/day.

Pharmacokinetics

Route	Onset	Peak	Duration
Oral	0.5–1 hr	3–4 hr	24 hr

Metabolism: Hepatic; T_1/2: 10–11 hr

Distribution: Crosses placenta; enters breast milk

Excretion: Urine

Adverse effects

·        CV: Angina pectoris, hypotension in salt- or volume-depleted patients, palpitations

·        Dermatologic: Rash, pruritus, diaphoresis, flushing

·        GI: Nausea, abdominal pain, vomiting, constipation

·        Respiratory: Cough, asthma, bronchitis, dyspnea, sinusitis

·        Other: Angioedema, impotence, decreased libido, asthenia, myalgia, arthralgia

Interactions

Drug-drug

·        Increased risk of hypersensitivity reactions with allopurinal

·        Increased coughing with capsaicin

·        Decreased antihypertensive effects with indomethacin and other NSAIDs

·        Increased lithium levels and neurotoxicity may occur if combined

·        Increased risk of hyperkalemia with potassium-sparing diuretics or potassium supplements

Nursing considerations

Assessment

·        History: Allergy to benazepril or other ACE inhibitors, impaired renal function, CHF, salt or volume depletion, lactation, pregnancy

·        Physical: Skin color, lesions, turgor; T; P, BP, peripheral perfusion; mucous membranes, bowel sounds, liver evaluation; urinalysis, LFTs, renal function tests, CBC and differential

Interventions

·        WARNING: Alert surgeon, note use of benazepril on patient's chart; the angiotensin II formation subsequent to compensatory renin release during surgery will be blocked; hypotension may be reversed with volume expansion.

·        Monitor patient for possible fall in BP secondary to reduction in fluid volume (excessive perspiration and dehydration, vomiting, diarrhea) because excessive hypotension may occur.

·        WARNING: Ensure that patient is not pregnant; fetal abnormalities and death have occurred if using during second or third trimester. Encourage use of contraceptive measures.

·        Reduce dosage in patients with impaired renal function.

Teaching points

·        Do not stop taking the medication without consulting your health care provider.

·        Be careful in any situation that may lead to a drop in blood pressure (diarrhea, sweating, vomiting, dehydration); if light-headedness or dizziness occurs, consult your health care provider.

·        You should not become pregnant while on this drug. Serious fetal abnormalities could occur; use of contraceptives is advised.

·        You may experience these side effects: GI upset, loss of appetite (transient effects; if persistent consult health care provider); light-headedness (transient; change position slowly, and limit activities to those that do not require alertness and precision); dry cough (irritating but not harmful; consult health care provider).

·        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.