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captopril (Capoten)

Tradename: Capoten. Indications: 1) hypertension - treatment of hypertensive urgency 2) congestive heart failure: 3) left ventricular systolic dysfunction after myocardial infarction 4) diabetic nephropathy 5) nondiabetic proteinuric nephropathy 6) cystinuria, cystine renal calculi [7] Contradindications: - pregnancy: - teratogenic in 1st trimester [8] - fetal or neonatal renal failure in 2nd or 3rd trimester - scleroderma renal crisis is exception [8] - safe in lactation [8] Dosage: - hypertension: - start 25 mg PO BID/TID, max 450 mg/day. - chronic heart failure - start 6.25-12.5 mg PO TID, max 150 mg/day - diabetic nephropathy: 25 mg PO TID Tabs: 12.5, 25, 50, 100 mg. Pharmacokinetics: 1) oral bioavailability is about 60% -> food impairs absorption [6] 2) 30% is bound to plasma proteins 3) 50% is metabolized by the liver 4) 30% is excreted into the urine 5) onset of action: (single dose) 15-60 minutes - maximum drop in BP at 30-90 minutes [9] 6) duration of action: (single dose) 6-12 hours 5) 1/2 life is 1.7 hours [4] in healthy individuals, but is prolonged in patients with renal failure or CHF Adverse effects: 1) common (> 10%) - transient, non-productive, dry cough 2) not common (1-10%) - dyspnea, oliguria, tachycardia, chest pain, palpitations, insomnia, paresthesias, headache, dizziness, fatigue, malaise, abdominal pain, vomiting, nausea, diarrhea, anorexia, constipation, rash, pruritus, alopecia, 3) uncommon (< 1%) - hypotension, hyperkalemia, neutropenia, agranulocytosis*, angioedema*, proteinuria, worsening of renal failure, disturbances in taste * side effects of angioedema & agranulocytosis may be more common in captopril than in other ACE inhibitors because of sulfhydryl group, especially in patients with connective tissue disease or serum creatinine > 1.5 mg/dL Drug interactions: 1) NSAIDs may reduce hypotensive effect 2) phenothiazines may increase pharmacologic effects of captopril 3) high risk of hypersensitivity reactions when used in combination with allopurinol 4) captopril increases serum levels of lithium & digoxin 5) agents that increase serum K+ a) K+ salts b) K+ sparing diuretics 1] spironolactone 2] triamterene Mechanism of action: - ACE inhibitors block conversion of angiotensin-1 to angiotensin-2 by inhibiting angiotensin converting enzyme Notes: - captopril improves symptoms of heart failure, improves exercise tolerance & improves functional capacity in patients with heart failure - captopril also attenuates ventricular enlargement & improves hemodynamics & survival in patients with left ventricular dysfunction secondary to myocardial infarction - it is likely that other ACE inhibitors have similar beneficial effects, but have been less well studied.

Interactions

drug interactions drug adverse effects (more general classes) monitor with ACE inhibitors

Related

angiotensin converting enzyme (ACE) angiotensin II (Giapreza) Captopril Prevention Project (CAPPP) captopril scan; ACE inhibitor renography; renal scintigraphy captopril-renin stimulation test ELITE II Study

General

angiotensin-converting enzyme (ACE) inhibitor carboxylic acid pyrrolidine; tetrahydropyrrole thiol; sulhydryl compound; mercaptan

Properties

INHIBITS: angiotensin converting enzyme MISC-INFO: elimination route LIVER KIDNEY 1/2life 6-8 HOURS 1.7 HOURS pregnancy-category D safety in lactation ?

Database Correlations

PUBCHEM correlations

References

  1. Goodman and Gilman's The Pharmacological Basis of Therapeutics, 8th ed. Gilman et al, eds. Permagon Press/McGraw Hill, 1990. pg 760-1
  2. The Pharmacological Basis of Therapeutics, 9th ed. Gilman et al, eds. Permagon Press/McGraw Hill, 1996
  3. Manual of Medical Therapeutics, 28th ed, Ewald & McKenzie (eds), Little, Brown & Co, Boston, 1995, pg 117
  4. Drug Information & Medication Formulary, Veterans Affairs, Central California Health Care System, 1st ed., Ravnan et al eds, 1998
  5. Kaiser Permanente Northern California Regional Drug Formulary, 1998
  6. Harrison's Principles of Internal Medicine, 14th ed. Fauci et al (eds), McGraw-Hill Inc. NY, 1998, pg 470
  7. Deprecated Reference
  8. Medical Knowledge Self Assessment Program (MKSAP) 17, American College of Physicians, Philadelphia 2015
  9. NEJM Knowledge+ Question of the Week. Sept 18, 2018 https://knowledgeplus.nejm.org/question-of-week/15/

Component-of

captopril/hydrochlorothiazide; captopril/HCTZ (Capozide)