Fosinopril dosage and administration

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Amr Marawan, M.D. [2], Ahmed Zaghw, M.D. [3]

Fosinopril

• Fosinopril sodium tablet

Fosinopril and Hydrochlorothiazide

• Fosinopril sodium and Hydrochlorothiazide tablet

Overview

Captopril tablet is an angiontensin converting enzyme inhibitor drug that is FDA approved for the treatment of hypertension, heart failure, left ventricular dysfunction after myocardial infarction, diabetic nephropathy. Adverse reactions include hypotension, rash, hyperkalemia, disorder of taste, cough. hypotension, rash, hyperkalemia, disorder of taste, cough.

Category

Antihypertensive Agents, Angiotensin Converting Enzyme Inhibitors. Editor-In-Chief: C. Michael Gibson, M.S., M.D. [4]; Associate Editor(s)-in-Chief: Amr Marawan, M.D. [5]

Dosage and Administration

Adults

The recommended initial dose of fosinopril Na tablets (fosinopril sodium tablets) is 10 mg once a day, both as monotherapy and when the drug is added to a diuretic. Dosage should then be adjusted according to blood pressure response at peak (2 to 6 hours) and trough (about 24 hours after dosing) blood levels. The usual dosage range needed to maintain a response at trough is 20 to 40 mg but some patients appear to have a further response to 80 mg. In some patients treated with once daily dosing, the antihypertensive effect may diminish toward the end of the dosing interval. If trough response is inadequate, dividing the daily dose should be considered. If blood pressure is not adequately controlled with fosinopril sodium alone, a diuretic may be added.

Concomitant administration of fosinopril with potassium supplements, potassium salt substitutes, or potassium-sparing diuretics can lead to increases of serum potassium.

In patients who are currently being treated with a diuretic, symptomatic hypotension occasionally can occur following the initial dose of fosinopril. To reduce the likelihood of hypotension, the diuretic should, if possible, be discontinued two to three days prior to beginning therapy with fosinopril Na tablets. Then, if blood pressure is not controlled with fosinopril alone, diuretic therapy should be resumed. If diuretic therapy cannot be discontinued, an initial dose of 10 mg of fosinopril Na tablets should be used with careful medical supervision for several hours and until blood pressure has stabilized.

Since concomitant administration of fosinopril with potassium supplements, or potassium-containing salt substitutes or potassium-sparing diuretics may lead to increases in serum potassium, they should be used with caution.

Pediatrics

In children, doses of fosinopril between 0.1 and 0.6 mg/kg have been studied and shown to reduce blood pressure to a similar extent. Based on this, the recommended dose of fosinopril in children weighing more than 50 kg is 5 to 10 mg once per day as monotherapy. An appropriate dosage strength is not available for children weighing less than 50 kg.

Heart Failure

Digitalis is not required for fosinopril to manifest improvements in exercise tolerance and symptoms. Most placebo-controlled clinical trial experience has been with both digitalis and diuretics present as background therapy.

The usual starting dose of fosinopril Na tablets should be 10 mg once daily. Following the initial dose of fosinopril Na tablets, the patient should be observed under medical supervision for at least two hours for the presence of hypotension or orthostasis and, if present, until blood pressure stabilizes. An initial dose of 5 mg is preferred in heart failure patients with moderate to severe renal failure or those who have been vigorously diuresed.

Dosage should be increased, over a several week period, to a dose that is maximal and tolerated but not exceeding 40 mg once daily. The usual effective dosage range is 20 to 40 mg once daily.

The appearance of hypotension, orthostasis, or azotemia early in dose titration should not preclude further careful dose titration. Consideration should be given to reducing the dose of concomitant diuretic.

For Hypertensive or Heart Failure Patients With Renal Impairment

In patients with impaired renal function, the total body clearance of fosinoprilat is approximately 50% slower than in patients with normal renal function. Since hepatobiliary elimination partially compensates for diminished renal elimination, the total body clearance of fosinoprilat does not differ appreciably with any degree of renal insufficiency (creatinine clearances <80 mL/min/1.73m2), including end-stage renal failure (creatinine clearance <10 mL/min/1.73m2). This relative constancy of body clearance of active fosinoprilat, resulting from the dual route of elimination, permits use of the usual dose in patients with any degree of renal impairment.

References

Adapted from the FDA Package Insert.