Capoten

Cap·o·ten (kp-tn)

A trademark for the drug captopril.

---

Capoten,

trademark for an angiotensin-converting enzyme inhibitor (captopril).

---

captopril

Acepril (UK), Apo-Capto (CA), Capoten, Ecopace (UK), Gen-Captopril (CA), Kaplon (UK), Novo-Captopril (CA), Nu-Capto (CA), Tensopril

Pharmacologic class: Angiotensin-converting enzyme (ACE) inhibitor

Therapeutic class: Antihypertensive

Pregnancy risk category C (first trimester), D (second and third trimesters)

FDA Boxed Warning

• When used during second or third trimester of pregnancy, drug may cause fetal injury and death. Discontinue as soon as possible when pregnancy is detected.

Action

Prevents conversion of angiotensin I to angiotensin II, which leads to decreased vasoconstriction and, ultimately, to lower blood pressure. Also decreases blood pressure by increasing plasma renin secretion from kidney and reducing aldosterone secretion from adrenal cortex. Decreased aldosterone secretion prevents sodium and water retention.

Availability

Tablets: 12.5 mg, 25 mg, 50 mg, 100 mg

⊘Indications and dosages

➣ Hypertension

Adults: 12.5 to 25 mg P.O. two to three times daily; may be increased up to 150/mg/day at 1- to 2-week intervals. Usual dosage is 50 mg t.i.d. If patient is receiving diuretics, start with 6.25 to 12.5 mg P.O. two to three times daily. If blood pressure isn't adequately controlled after 1 to 2 weeks, add diuretic, as prescribed. If further blood pressure decrease is needed, dosage may be raised to 150 mg P.O. t.i.d. while patient continues on diuretic. Maximum dosage is 450 mg/day.

➣ Heart failure

Adults: Usual initial dosage is 25 mg P.O. t.i.d. After increasing to 50 mg P.O. t.i.d. (if indicated), do not increase dosage further for 2 weeks, to determine satisfactory response. Don't exceed 450 mg/day.

➣ Left ventricular dysfunction after myocardial infarction

Adults: 6.25 mg P.O. as a test dose, followed by 12.5 mg t.i.d. May increase up to 50 mg t.i.d.

➣ Diabetic nephropathy

Adults: 25 mg P.O. t.i.d.

Dosage adjustment

• Renal impairment

Off-label uses

• Bartter's syndrome
• Hypertension associated with scleroderma
• Management of hypertensive crisis
• Raynaud's syndrome
• Rheumatoid arthritis
• Severe childhood hypertension

Contraindications

• Hypersensitivity to drug or other ACE inhibitors
• Angioedema (hereditary or idiopathic)
• Pregnancy

Precautions

Use cautiously in:
• renal or hepatic impairment, hypovolemia, hyponatremia, aortic stenosis and hypertrophic cardiomyopathy, cardiac or cerebrovascular insufficiency, systemic lupus erythematous
• family history of angioedema
• black patients with hypertension
• elderly patients
• breastfeeding patients
• children.

Administration

• Discontinue other antihypertensives 1 week before starting captopril, if possible.
• Give 1 hour before meals on empty stomach.

Route	Onset	Peak	Duration
P.O.	0.25-1 hr	1-1.5 hr	6-12 hr

Adverse reactions

CNS: headache, dizziness, drowsiness, fatigue, weakness, insomnia

CV: angina pectoris, tachycardia, hypotension

EENT: sinusitis

GI: nausea, diarrhea, anorexia

GU: proteinuria, erectile dysfunction, decreased libido, gynecomastia, renal failure

Hematologic: anemia, agranulocytosis, leukopenia, pancytopenia, thrombocytopenia

Metabolic: hyperkalemia

Respiratory: cough, asthma, bronchitis, dyspnea, eosinophilic pneumonitis

Skin: rash, angioedema

Other: altered taste, fever

Interactions

Drug-drug. Allopurinol: increased risk of hypersensitivity reaction

Antacids: decreased captopril absorption

Antihypertensives, general anesthetics that lower blood pressure, nitrates, phenothiazines: additive hypotension

Cyclosporine: hyperkalemia

Digoxin, lithium: increased blood levels of these drugs, increased risk of toxicity

Epoetin alfa: additive hyperkalemia

Indomethacin: reduced antihypertensive effect of captopril

Nonsteroidal anti-inflammatory drugs: decreased antihypertensive response

Potassium-sparing diuretics, potassium supplements: hyperkalemia

Probenecid: decreased elimination and increased blood level of captopril

Drug-diagnostic tests. Alanine aminotransferase, alkaline phosphatase, aspartate aminotransferase, bilirubin, blood urea nitrogen, creatinine, potassium: increased levels

Granulocytes, hemoglobin, platelets, red blood cells, sodium, white blood cells: decreased levels

Urine acetone: false-positive result

Drug-food. Any food: decreased captopril absorption

Salt substitutes containing potassium: hyperkalemia

Drug-herbs. Capsaicin, yohimbine: cough

Drug-behaviors. Acute alcohol ingestion: additive hypotension

Patient monitoring

☞ Monitor for sudden blood pressure drop within 3 hours of initial dose if patient is receiving concurrent diuretics and on a low-sodium diet.
• Monitor hematologic, kidney, and liver function test results.
• Check for proteinuria monthly and after first 9 months of therapy.

Patient teaching

• Tell patient to take drug 1 hour before meals on empty stomach.
• Advise patient to report fever, rash, sore throat, mouth sores, fast or irregular heartbeat, chest pain, or cough.
• Inform patient that dizziness, fainting, and light-headedness usually disappear once his body adjusts to drug.
• Tell patient his ability to taste may decrease during first 2 to 3 months of therapy.
• Caution patient to avoid over-the-counter medications unless approved by prescriber.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, foods, herbs, and behaviors mentioned above.

---

Capoten^®

Captopril, see there