Enalapril for Cats: Kidney Disease and Heart Use
By Dr. Zubair Khalid, DVM, MS, PhD ·
Enalapril for cats dosage is never a number you pick yourself. Your veterinarian calculates it from your cat's weight, kidney values, blood pressure, and the condition being treated, then adjusts it over time. This article is educational and is not a substitute for veterinary diagnosis or treatment.
Quick Answer
- Enalapril is an ACE inhibitor used in cats for heart disease, high blood pressure, and protein-losing kidney disease [1].
- The dose is individualized. Your veterinarian decides the amount and how often it is given, then rechecks bloodwork to fine-tune it.
- ACE inhibitors widen blood vessels, which lowers blood pressure and makes it easier for the heart to pump [1].
- They also increase blood flow to the kidneys and reduce how much protein leaks into the urine [1].
- Cats on enalapril need periodic blood tests to watch kidney values and electrolytes, especially if they also take a diuretic.
What Enalapril Is and What Veterinarians Use It For
Enalapril is an angiotensin-converting enzyme inhibitor, usually called an ACE inhibitor. It is prescribed to both people and animals to treat high blood pressure, cardiomyopathy, and heart disease [1]. In cats, it shows up most often in two situations: heart disease and kidney disease with protein loss.
Enalapril for cats with HCM and other heart disease
Hypertrophic cardiomyopathy (HCM) is the most common heart disease in cats. Treatment goals for feline heart disease include limiting damage to the heart muscle, controlling fluid buildup in and around the lungs, improving circulation, and keeping the heart rate and rhythm steady [2]. The drug chosen depends on the specific type of heart disease your cat has [2].
Enalapril is not a cure for HCM. It is one part of a plan that may include other medications. If your cat has HCM, your veterinarian will explain what enalapril is expected to do in your cat's case and what it will not do.
Enalapril for cats with kidney disease
Enalapril can be used to treat kidney diseases such as chronic renal failure and protein-losing nephropathies [1]. Protein-losing nephropathy means the kidneys are leaking protein into the urine when they should be holding onto it. ACE inhibitors can increase blood flow to the kidneys and decrease the amount of protein being lost into the urine [1]. That is why they are helpful in some cats with kidney disease.
Not every cat with kidney disease needs an ACE inhibitor. The decision usually comes down to whether protein is being lost in the urine and whether blood pressure is under control. For a broader look at staging and daily management, see Chronic Kidney Disease CKD in Cats: Stage 1-4 Renal Management Guide.
Benazepril for cats with kidney disease
Benazepril is another ACE inhibitor used in cats with chronic kidney disease. Treating feline CKD often involves daily antiproteinuric medication, and giving pills every day can be hard on both the cat and the owner [3]. One approach studied in cats is putting benazepril into a highly palatable renal diet so the cat absorbs the drug throughout the day while eating small meals [3]. That study found the medicated diet produced lower overall drug exposure than once-daily benazepril tablets, but ACE inhibition was at least equivalent in CKD cats and higher in healthy cats [3].
The practical point for owners: benazepril and enalapril are close cousins, and your veterinarian may prefer one over the other based on your cat's kidney values, blood pressure, and how easy your cat is to medicate. If pill time is a daily battle, say so. There are often options.
How Enalapril Works
When blood vessels narrow, blood pressure rises and the heart has to work harder to push blood and oxygen through the body [1]. Enalapril widens the diameter of those vessels, which lowers blood pressure and makes the heart's job easier [1].
The same widening happens in the small vessels inside the kidneys. That extra blood flow supports kidney function, and the drug also reduces how much protein escapes from the kidneys into the urine [1].
This is why one medication can help two different organ systems. It is also why monitoring matters. A drug that changes blood flow and blood pressure can shift kidney values and electrolyte levels, especially in a cat already dealing with heart failure or kidney disease.
Enalapril for Cats Dosage: How Dosing Works
Who decides the dose
Your veterinarian does. There is no safe at-home dose chart for enalapril in cats. The right amount depends on your cat's weight, kidney values, blood pressure, other medications, and the condition being treated. Doses are often started low and adjusted after recheck bloodwork.
How it is given
Enalapril is given by mouth, usually as a tablet or a compounded liquid. It can typically be given with or without food, but follow your veterinarian's instructions exactly. Medications for cats with cardiovascular disease must be given exactly as prescribed, because giving them incorrectly can make them ineffective or even cause serious harm [2].
A few practical tips:
- Give the dose at the same time each day to keep levels steady.
- If your cat spits out a pill, do not guess at a replacement dose. Call your veterinarian.
- Never split, crush, or hide a tablet in food unless your veterinarian says it is fine for that specific product.
- Keep a simple log of doses given. It helps your veterinarian adjust the plan.
What to do about a missed dose
If you miss a dose, give it when you remember, unless it is almost time for the next one. In that case, skip the missed dose and go back to your regular schedule. Do not double up to catch up. If you are unsure, call your veterinary clinic and ask.
Side Effects of Enalapril in Cats
Most cats tolerate enalapril well when the dose is right. Problems are more likely in cats who already have kidney failure, heart disease, or other ongoing medical conditions [1].
| Side effect | How common or serious | What to do |
|---|---|---|
| Vomiting | Uncommon but possible, can be serious if it continues | Call your veterinarian if it happens more than once or lasts past a day |
| Diarrhea | Uncommon | Call your veterinarian if it lasts more than 24 hours or your cat seems unwell |
| Lethargy or weakness | Can be a sign of low blood pressure, more likely in cats with underlying disease [1] | Contact your veterinarian the same day |
| Low blood pressure (hypotension) | Serious, most often seen with too much medication [1] | Emergency care if your cat collapses, seems wobbly, or breathes oddly |
| Rising kidney values | Possible in cats on enalapril plus a diuretic, since azotemia is common in cats treated for congestive heart failure [4] | Found on bloodwork, your veterinarian will adjust treatment |
| Reduced appetite | Uncommon | Mention it at the next visit, or sooner if your cat stops eating |
Azotemia means higher-than-normal kidney waste products in the blood. It is common in cats being treated for congestive heart failure, showing up in 44% of cats at the time heart failure was first diagnosed in one study, and kidney injury was documented in 66% of cats during treatment [4]. Higher furosemide doses were linked to rising creatinine [4]. This is not a reason to avoid treatment. It is a reason to keep recheck appointments.
Who Should Not Take Enalapril and Drug Interactions
Enalapril is not right for every cat. Your veterinarian will weigh the risks if your cat has:
- Dehydration or is not eating or drinking normally
- Very low blood pressure
- Severe kidney disease with unstable values
- A history of reacting badly to ACE inhibitors
Tell your veterinarian about every medication, supplement, and diet your cat receives. This matters most for:
- Diuretics such as furosemide. These are commonly used together with ACE inhibitors in heart failure, but the combination raises the risk of kidney injury and azotemia [4]. Your veterinarian will monitor bloodwork closely.
- Other blood pressure medications. Stacking drugs that lower blood pressure can push it too low.
- Potassium supplements or potassium-sparing diuretics. ACE inhibitors can raise potassium levels.
- NSAIDs and other kidney-stressing drugs. These add risk in a cat whose kidneys are already working hard.
Never start a new medication or supplement without asking your veterinarian first.
Overdose and When to Call for Help
Too much enalapril can cause low blood pressure, lethargy, weakness, vomiting, and diarrhea [1]. These signs are more likely to develop in pets who already have kidney failure or heart disease [1].
If you think your cat ate extra tablets, or you are not sure how much was swallowed, call for help right away. Do not wait for symptoms.
- Pet Poison Helpline: (855) 764-7661
- ASPCA Animal Poison Control Center: (888) 426-4435
Have your cat's weight, the medication strength, and your best guess at how many tablets were involved ready when you call. Then call your own veterinarian or the nearest emergency clinic.
Limitations and When to Contact a Veterinarian
Enalapril helps many cats, but it does not fix every heart or kidney problem, and it cannot replace regular monitoring. Cats with heart disease and kidney disease often need dose changes over time as their values shift. Your individual cat's case needs a veterinarian who knows the full history.
Call your veterinarian the same day if your cat:
- Vomits more than once or cannot keep food down
- Seems weak, wobbly, or unusually quiet
- Stops eating or drinking
- Has diarrhea that lasts more than a day
Go to an emergency clinic now if your cat:
- Collapses or cannot stand
- Breathes fast, with effort, or with the mouth open
- Has a seizure or seems disoriented
- May have eaten a large number of tablets
Schedule a routine visit if:
- Your cat is due for a blood pressure check or bloodwork
- You are running low on medication and need a refill
- You are struggling to give the pills and want to talk about other options
For cats with kidney disease, diet and medication work together. If you are reviewing food choices, What Cat Food Is Best For Kidney Disease covers the basics, and Treatment For Kidney Failure In Older Cats explains what supportive care can look like as kidney disease advances.
Frequently Asked Questions
Can I give my cat enalapril without a prescription?
No. Enalapril is a prescription medication, and the dose must be calculated for your cat by a veterinarian. Giving a human dose or a dose meant for another pet can cause low blood pressure and other serious problems.
Does enalapril cure kidney disease in cats?
No. It can slow protein loss and support blood flow to the kidneys, but it does not reverse kidney damage. It works best as one part of a full plan that includes diet, blood pressure control, and regular bloodwork.
How long does it take to see a difference?
Some effects, like lower blood pressure, happen within days. Changes in urine protein are usually judged on recheck testing over weeks to months. Your veterinarian will set the schedule based on your cat's condition.
Can enalapril and benazepril be used together?
They are not typically combined, since both are ACE inhibitors and do the same basic job. Your veterinarian will choose one and adjust it based on your cat's response and lab results.
Will my cat need blood tests while taking enalapril?
Yes, usually. Recheck bloodwork looks at kidney values and electrolytes, and blood pressure may be measured too. Cats with heart failure on diuretics need this monitoring because azotemia is common during treatment [4].
Related Articles
- Chronic Kidney Disease in Cats
- Chronic Kidney Disease CKD in Cats: Stage 1-4 Renal Management Guide
- Treatment For Kidney Failure In Older Cats
- What Cat Food Is Best For Kidney Disease
- Omega-3 Fish Oil for Cats: Dose for Skin Kidney and Joints
- Symptoms Of Kidney Disease In My Cat
References
- What is Enalapril?. Pet Poison Helpline.
- Treatment of Cardiovascular Disease in Cats - Cat Owners. Merck Veterinary Manual.
- Why incorporating benazepril into a renal diet may improve treatment efficiency and compliance in cats with chronic kidney disease. Frontiers in veterinary science, 2026.
- Frequency and progression of azotemia during acute and chronic treatment of congestive heart failure in cats. Journal of veterinary internal medicine, 2025.