From the Guidelines
The initial dose of enalaprilat for a patient with CHF and hypertensive crisis is 1.25 mg administered intravenously over 5 minutes, as recommended by the 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults 1. This dose can be repeated every 6 hours as needed based on the patient's blood pressure response. For patients who are volume-depleted or have renal insufficiency, a lower starting dose of 0.625 mg should be considered, as suggested by the 2007 guidelines for the management of spontaneous intracerebral hemorrhage in adults 1. Close monitoring of blood pressure is essential during administration, as ACE inhibitors can cause a rapid drop in blood pressure, especially in patients who are volume-depleted or on diuretics. Enalaprilat works by inhibiting the conversion of angiotensin I to angiotensin II, thereby reducing peripheral vascular resistance and decreasing afterload, which helps improve cardiac output in CHF patients while simultaneously lowering blood pressure. Some key points to consider when administering enalaprilat include:
- Potential adverse effects, such as hypotension, hyperkalemia, and worsening renal function, which should be closely monitored 1.
- The importance of continuous cardiac monitoring during administration in the acute setting.
- The need for individualized dosing based on the patient's blood pressure response and clinical status. It is also worth noting that other studies, such as the seventh report of the joint national committee on prevention, detection, evaluation, and treatment of high blood pressure 1, provide additional guidance on the management of hypertensive emergencies, but the most recent and highest quality evidence supports the use of enalaprilat at a dose of 1.25 mg IV as the initial treatment for CHF and hypertensive crisis.
From the FDA Drug Label
For patients on diuretic therapy the recommended starting dose for hypertension is 0. 625 mg administered intravenously over a five minute period; The starting dose should be no greater than 0. 625 mg administered intravenously over a period of no less than five minutes and preferably longer (up to one hour).
The initial dose of enalaprilat (IV) for a patient with Congestive Heart Failure (CHF) and hypertensive crisis is 0.625 mg administered intravenously over a period of no less than five minutes and preferably longer (up to one hour) 2.
From the Research
Enalaprilat Dosage for Congestive Heart Failure and Hypertensive Crisis
- The initial dose of enalaprilat for patients with Congestive Heart Failure (CHF) and hypertensive crisis is a topic of discussion in several studies 3, 4, 5.
- According to a study published in the Archives of Internal Medicine in 1995, the recommended initial dose of enalaprilat is 0.625 mg, as doses above this do not alter response rates or the magnitude of blood pressure reduction 3.
- Another study published in the Indian Heart Journal in 2004 used a dose of 1.25 mg of intravenous enalaprilat to manage severe hypertension in patients requiring an emergency reduction in blood pressure 4.
- A study published in Cardiology in 1999 used a low dose of intravenous enalaprilat (0.004 mg/kg) as a bolus or continuous 1-hour infusion to improve hemodynamics and systemic oxygenation in patients with congestive heart failure due to ischemic heart disease with acute decompensation refractory to other therapies 5.
Key Findings
- The response rates to different doses of enalaprilat (0.625,1.25,2.5, and 5 mg) were similar, with no significant differences in changes in systolic, diastolic, and mean arterial blood pressure 3.
- Enalaprilat is a safe antihypertensive drug with moderate efficacy in the treatment of hypertensive crisis 3.
- The presence of CHF does not appreciably alter the pharmacokinetic behavior of enalapril 6.
- Enalapril appears to be well tolerated, with few serious adverse effects being reported 7.