ENALAPRILAT
Clinical safety rating: avoid
Contraindicated (not allowed)
Enalaprilat is an angiotensin-converting enzyme (ACE) inhibitor that blocks the conversion of angiotensin I to angiotensin II, reducing vasoconstriction and aldosterone secretion, leading to decreased blood pressure and cardiac workload.
| Metabolism | Enalaprilat is minimally metabolized; it is the active metabolite of enalapril. No significant hepatic metabolism. |
| Excretion | Renal: 60-80% unchanged; biliary/fecal: minimal (<10%) |
| Half-life | Terminal half-life: 35 hours (prolonged in renal impairment; accumulates with CrCl <30 mL/min) |
| Protein binding | 50-60% (primarily albumin, minimal binding to other proteins) |
| Volume of Distribution | ~0.7 L/kg (large, indicates extensive tissue distribution; does not cross blood-brain barrier well) |
| Bioavailability | IV: 100% (given as active drug); oral: N/A (enalaprilat is not orally administered; enalapril oral bioavailability ~60%) |
| Onset of Action | IV: 5-15 minutes; oral: N/A (prodrug enalapril, requires hepatic activation) |
| Duration of Action | 24 hours; dose-dependent, sustained effect in heart failure and hypertension |
1.25 mg IV over 5 minutes every 6 hours; may increase to 5 mg IV every 6 hours if needed.
| Dosage form | INJECTABLE |
| Renal impairment | GFR 30-60 mL/min: 0.625 mg IV every 6 hours; GFR <30 mL/min (including dialysis): 0.625 mg IV every 6 hours, titrate cautiously. |
| Liver impairment | No specific dose adjustment recommended; monitor for hypotension and hyperkalemia. |
| Pediatric use | Children ≥1 month: 5-10 mcg/kg/dose IV every 8-12 hours, max 1.25 mg/dose. |
| Geriatric use | Initiate at 0.625 mg IV every 6 hours; titrate slowly due to increased risk of hypotension and renal impairment. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
NSAIDs may diminish the antihypertensive effect Lithium levels may be increased Risk of angioedema can occur at any time discontinue immediately.
| Breastfeeding | Enalaprilat is excreted into breast milk in low concentrations (estimated infant dose <0.2% of maternal weight-adjusted dose); M/P ratio not well-established. Compatible with breast-feeding if infant renal function monitored; caution in preterm or renally impaired infants. |
| Teratogenic Risk | First trimester: Association with congenital malformations (cardiac, CNS) based on retrospective data; second and third trimesters: Known fetal toxicity including oligohydramnios, fetal hypotension, renal failure, skull hypoplasia, and death due to renin-angiotensin system blockade. |
■ FDA Black Box Warning
Fetal toxicity: Drugs acting directly on the renin-angiotensin system can cause injury and death to the developing fetus. Discontinue as soon as pregnancy is detected.
| Common Effects | heart failure |
| Serious Effects |
["History of angioedema related to previous ACE inhibitor therapy","Concomitant use with aliskiren in patients with diabetes or renal impairment (GFR <60 mL/min)","Hypersensitivity to enalaprilat or any ACE inhibitor"]
| Precautions | ["Angioedema","Hypotension","Renal impairment","Hyperkalemia","Cough"] |
Loading safety data…
| Fetal Monitoring | Fetal ultrasound for amniotic fluid volume and renal function in second/third trimesters; maternal blood pressure, renal function, serum potassium, and urine protein. Monitor for signs of oligohydramnios or fetal distress. |
| Fertility Effects | No significant adverse effects on human fertility reported; animal studies show no impairment of fertility at clinically relevant doses. |