ADMINISTRATION ROUTES:
PO, NG
ALTERNATIVE NAMES:
Capoten
ICU INDICATIONS:
-
Hypertension
-
Congestive heart failure or left ventricular dysfunction after myocardial infarction
-
Diabetic nephropathy
PRESENTATION AND ADMINISTRATION:
PO / NG:
Apo-captopril & capoten tablets (12.5mg, 25mg, 50 mg white tablets) Capoten solution (5 mg/mL) clear and colourless
Tablets can be crushed for NG administration. Liquid is also available
DOSAGE:
PO/NG:
6.25mg q8hrly increased to maximum of 50 mg q8hrly
DOSAGE IN RENAL FAILURE AND RENAL REPLACEMENT THERAPY:
Dose in renal impairment
GFR (ml/min) | DOSE |
---|---|
<10 | 6.25 mg or less and increase gradually |
10-20 | 6.25 mg or less and increase gradually |
>20-50 | 6.25 mg or less and increase gradually |
Dose in renal replacement therapy
MODALITY | DOSE |
---|---|
CAPD | 6.25 mg or less and increase gradually |
HD | 6.25 mg or less and increase gradually |
CVVHDF | 6.25 mg or less and increase gradually |
Note: There have been reports of an association of hypersensitivity-like (anaphylactoid) reactions during haemodialysis with high-flux dialysis membranes (e.g. AN69) in patients receiving ACE inhibitors
DOSAGE IN PAEDIATRICS:
0.1 mg/kg q8hrly. Increase if required to a maximum of 2 mg/kg q8hrly
CLINICAL PHARMACOLOGY:
Captopril is a specific competitive inhibitor of angiotensin I-converting enzyme (ACE), the enzyme responsible for the conversion of angiotensin I to angiotensin II
CONTRAINDICATIONS:
-
Hypersensitivity to captopril or any other angiotensin-converting enzyme inhibitor (e.g. a patient who has experienced angioedema during therapy with any other ACE inhibitor)
-
Cardiogenic shock
WARNINGS:
Anaphylactoid and Possibly Related Reactions
Captopril can cause anaphylactoid reactions
Head and Neck Angioedema
Angioedema involving the extremities, face, lips, mucous membranes, tongue, glottis or larynx has been seen in patients treated with ACE inhibitors, including captopril. If angioedema involves the tongue, glottis or larynx, airway obstruction may occur and be fatal. Swelling confined to the face, mucous membranes of the mouth, lips and extremities has usually resolved with discontinuation of captopril; some cases required medical therapy
Intestinal Angioedema
Intestinal angioedema has been reported in patients treated with ACE inhibitors. These patients presented with abdominal pain (with or without nausea or vomiting); in some cases there was no prior history of facial angioedema and C-1 esterase levels were normal
Neutropaenia/Agranulocytosis
Neutropaenia (<1000/mm3) with myeloid hypoplasia has resulted from use of captopril
Hypotension in Heart Failure Patients
Caution should be observed when initiating therapy in patients with heart failure. Patients with heart failure given captopril commonly have some reduction in blood pressure. In patients with symptomatic hypotension this may require temporarily reducing the dose of captopril, or diuretic, or both, and volume repletion
Hepatic Failure
Rarely, ACE inhibitors have been associated with a syndrome that starts with cholestatic jaundice and progresses to fulminant hepatic necrosis and (sometimes) death. The mechanism of this syndrome is not understood. Patients receiving ACE inhibitors who develop jaundice or marked elevations of hepatic enzymes should discontinue the ACE inhibitor
PRECAUTIONS:
General:
Some patients with renal disease, particularly those with severe renal artery stenosis, have developed increases in serum creatinine after reduction of blood pressure with captopril. Captopril dosage reduction and/or discontinuation of diuretic may be required. Elevations in serum potassium have been observed in some patients treated with ACE inhibitors, including captopril
Presumably due to the inhibition of the degradation of endogenous bradykinin, persistent nonproductive cough has been reported with all ACE inhibitors, always resolving after discontinuation of therapy. ACE inhibitor-induced cough should be considered in the differential diagnosis of cough
Laboratory Tests:
No tests in addition to routine ICU tests are required
Drug/Laboratory Test Interactions:
Captopril may cause a false-positive urine test for acetone
IMPORTANT DRUG INTERACTIONS IN ICU:
Increased serum lithium levels and symptoms of lithium toxicity have been reported in patients receiving concomitant lithium and ACE inhibitor therapy.
The risk of hypotension increases if captopril is co-administered with other antihypertensives
ADVERSE REACTIONS:
Body as a Whole:
Gynaecomastia, anaphylactoid reactions, angioedema
Cardiovascular:
Cardiac arrest, cerebrovascular accident / insufficiency, rhythm disturbances, orthostatic hypotension, syncope
Dermatological:
Bullous pemphigus, erythema multiforme (Stevens Johnson syndrome), exfoliative dermatitis
Gastrointestinal:
Pancreatitis, glossitis, dyspepsia, jaundice, hepatitis, rare causes of hepatic necrosis, cholestasis
Haematological:
Anaemia (including cases of haemolytic anaemia), thrombocytopaenia, neutropaenia
Metabolic:
Hyponatraemia
Musculoskeletal:
Myalgia, myasthenia
Nervous system:
Ataxia, confusion, depression, nervousness, somnolence
Respiratory system:
Bronchospasm, eosinophilic pneumonia, angioedema
Urogenital system:
Renal failure, proteinuria