Benazepril (Lotensin) Risks, Warnings, and Complications

HARM TO AN UNBORN BABY: Benazepril and other drugs that affect the renin angiotensin aldosterone system can cause birth defects in an unborn baby if they are used during the second and third trimesters of pregnancy. Benazepril can lead to compromised renal function in the fetus, resulting in oligohydramnios (too little amniotic fluid). This, in turn, can lead to skeletal deformities, underdevelopment of the baby’s lungs, low blood pressure, decreased renal function, and renal failure. Due to these complications, the use of benazepril in pregnant women is associated with an increased risk of fetal and neonatal death. Before starting benazepril, tell your doctor if you are pregnant, could be pregnant, are planning a pregnancy in the near future, or are breastfeeding. Stop taking benazepril and call your doctor immediately if you become pregnant while on this medicine. Talk about appropriate birth control with your healthcare provider while on this medicine.

ANGIOEDEMA: Angioedema is a potentially life-threatening complication in patients treated with benazepril. It refers to a swelling of the eyes, face, lips, tongue, throat, hands, lower legs, ankles, or feet. It can be fatal if there is an obstruction of the airway.  Stop taking benazepril and seek emergency medical care if you develop swelling, hoarseness, or difficulty breathing. The risk of ACE inhibitor associated angioedema is higher in Black patients. Those taking certain drugs such as temsirolimus, sirolimus, or everolimus, along with an ACE inhibitor, are also at an increased risk of this serious compilation. 

Swelling in the intestines can occur as a result of ACE inhibitor use, causing symptoms such as nausea and vomiting. The intestinal swelling is sometimes discovered only in imaging studies such as an abdominal CT scan. There is resolution of the symptoms when the ACE inhibitor is stopped.

SEVERE ALLERGIC REACTION: There are case reports of severe allergic reactions, including life-threatening anaphylactoid reactions (throat closing), in patients receiving ACE inhibitors. The risk of this occurring is higher in people receiving hymenoptera venom immunotherapy for desensitization against insect bites, those undergoing dialysis, and people with impaired renal function. Seek emergency medical help if you develop hoarseness or trouble breathing or swallowing.

WORSENING RENAL FUNCTION AND KIDNEY FAILURE: Your doctor may monitor renal function periodically during ACE inhibitor therapy because these drugs can cause changes in kidney function, including possible acute renal failure. Patients with medical conditions such as chronic kidney disease, renal artery stenosis, severe congestive heart failure, recent heart attack, or volume depletion are at a higher risk of developing acute renal failure on benazepril.  Tell your doctor right away if you are urinating less than usual, as this can be a sign of your kidneys not working properly. Your doctor may ask you to stop taking this medicine if you develop a clinically significant decrease in renal function. 

HYPOTENSION: Benazepril lowers blood pressure and can sometimes cause your blood pressure to fall too low. This can be complicated by low urine volume, progressive azotemia (buildup of nitrogenous substances in the body), acute renal failure, and even death. Those at risk of hypotension include people with ischemic heart disease, cerebrovascular disease, heart failure and systolic blood pressure below 100 mm Hg, low blood sodium levels, high-dose diuretic therapy (water pills), those undergoing kidney dialysis, people with severe volume and/or salt depletion (dehydration) due to any cause, and those taking other antihypertensive agents to lower blood pressure. Talk to your doctor about how often you should monitor blood pressure and what to do if your blood pressure is low. Drink enough fluids while on this medicine. If you feel dizzy or lightheaded on benazepril, get up slowly from a sitting or lying position to prevent falls. Tell your provider if this side effect persists.

HYPERKALEMIA: Drugs such as benazepril that inhibit the renin angiotensin system can lead to high serum potassium levels (hyperkalemia). Your doctor will monitor potassium levels periodically while you are taking benazepril. Risk factors for this adverse effect include renal insufficiency and diabetes mellitus. Those who are taking potassium supplements, potassium-containing salt substitutes, or potassium-sparing diuretics (water pills) are also at greater risk of hyperkalemia. If you take lithium, your doctor may lower your dose or recommend frequent monitoring of serum lithium levels. Tell your doctor without delay if you develop symptoms such as nausea, muscle weakness, or heart rhythm changes.

LIVER FAILURE: For unclear reasons, some patients receiving benazepril or other ACE inhibitors can develop jaundice, which can progress to fulminant hepatic necrosis (liver failure) and even death. Tell your doctor without delay if you develop abdominal pain, yellowing of the skin or eyes, or dark urine after starting benazepril. Your healthcare provider will discontinue this medication if you develop jaundice or a marked increase in liver enzymes.