Medications for Cats with Heart Disease

For more information regarding the following medications, and Wikipedia and PetMD are just some excellent online resources.  

Medications can be purchased either at a regular pharmacy-Target and Kroger offer $4.00 generics for many of those listed below-or from the vet (but usually more expensive than a regular pharmacy), and the online pet pharmacy Road Runner.  Many pet stores and online pet stores carry supplements and medicines.  Call your local pharmacy and shop online to compare prices and to find what is affordable and convenient for you.

What Meds and Supplements Did Myrna Take?

Myrna’s medication needs changed over the course of the six years and nine months that she lived with the disease.  At first, she began with a couple meds and then after two months, was up to five.  Three years later, she was up to six, then seven.  About 2012 we added Valium to help her use the litter box because she was going out of the box-probably due to the frequent need to urinate due to the diuretic medication Lasix.  Eventually, she was on Pepcid for stomach acid.  We added sucralfate for stomach ulcers.  Then at times she needed Mirtazapine and Cerenia to help her eat.  She took a variety of vitamins, minerals, and supplements to improve her body condition, help the heart, replace what the heart meds removed, and to give her additional kidney support.  She put up with a lot; she endured a lot.  But all of it helped her live a long, healthy life and her kidneys stayed strong until the end despite the high levels of Lasix and then Torsemide that she took to better manage CHF. 

Medications for Cats with Heart Disease

For more information regarding the following medications, and Wikipedia and PetMD are some of the excellent online resources.  Each medicine and supplement discussed below is linked to a page of information. Feel free to search the above sites for additional information.

Medications can be purchased either at a regular pharmacy-Target and Kroger offer $4.00 generics for many of those listed below-or some from the vet (but usually more expensive than a regular pharmacy), and at online pet pharmacies such as Road Runner.  Call your local pharmacy and shop online to compare prices and to find what is affordable and convenient for you.

*Please remember that HCM or cats with heart disease cannot have any form of steroid medication. Steroids retain fluids and dangerously so for HCM cats-which is the opposite of what you want.


These following meds (other than Valium) are what you should consider for your heart diseased/HCM cat. Depending on the extent of the heart disease, a cat may not need every medication that Myrna receives.  They may receive something such as lasix and atenolol at first, then have others added as the disease progresses or as symptoms appear.    

 1) Valium was given to Myrna for litter box use and can be safely used by heart diseased cats to help solve any anxiety issues as long as the cat can tolerate it.   It is the only medication that as far as studies have shown, is not contraindicated with Plavix.  A cat on Plavix should not take psychotropics such as Prozac or stomach medications such as Prilosec.  The FDA issued a warning a few years ago that psychotropics and anti-acid stomach medications interfere with the blood clotting properties of Plavix.  A cat with heart disease needs to take Plavix to prevent clots from forming.  She received Valium four times a day for a total of almost 2 mg.

2) Myrna took baby buffered aspirin 81 mg once a day on Wednesdays and Saturdays because, in general, cats cannot take and tolerate aspirin well.  Therefore, they need to space the aspirin 72 hours apart.  Your cat may or may not be able to tolerate aspirin and blood work is needed constantly at first to monitor liver and kidney function. If the cat begins to vomit each time you give aspirin, then the aspirin needs to be stopped.  And of course, any time a new med is introduced and your cat begins to have stomach upsets, it might be the new med and the cat needs to either be given time to adjust, or the med needs to be decreased until the regular dose can be tolerated, or the med suspended altogether.  Always discuss medication needs and changes with the vet.

3) Myrna Loy took a 1/4 tab once a day of Plavix, the blood thinner, to prevent clots.  Clots form as blood pools in the heart because the heart cannot sufficiently pump out all the fluid it takes in. Thinner blood is also easier for the heart to circulate.  An article that discusses how Plavix is contraindicated with stomach anti-acid meds and psychotropics. (The article is a few years old and is outdated regarding generic Plavix which does exist now in the U.S.) Here is an article discussing that Plavix has been shown to be effective in cats. 

4) She took a 1/4 tab of Atenolol BID or twice a day-a beta blocker-which slows the heart rate, lowers the blood pressure which helps the heart not work so hard.  For four years, Myrna took 1/4 tab once a day.  This was adjusted to 1/4 BID (twice a day) as of 9/8/14 since her heart rate was becoming higher and she developed afib (abnormal heart beat.)

5)  She took a 1/2 tab twice a day of Enalapril-an ACE inhibitor-it keeps veins opened and from being restricted, aids in reducing sodium retention and therefore fluid in the body, and thereby lowers blood pressure. ACE inhibitors are also Fortekor (Europe) or benazepril.

6) Diuretic information:  There are three main diurectics-Lasix, Torasemide, and Thiazide. Myrna began with Lasix and used it for five years before switching to Torsemide in January, 2015.   We were going to add Thiazide in addition to Torasemide due to Torasemide’s inability to get rid of all of the congestion in her lungs.  Congestion or CHF was difficult to get rid of due to the damage to her lungs by the chylothorax fluid that created pits within the lungs.  This condition meant the lungs were unable to expand and take in oxygen, get rid of carbon dioxide, and get rid of fluid sufficiently.  Instead, the damaged pits held fluid.  Her kidneys-while the values were great-had seemed to hit a tolerance for Torasemide, meaning, they seemed oblivious to the medication’s diuretic properties and were not assisting the body in drawing fluid from the lungs to the kidney system. 

Lasix is a diuretic, a fluid reducer, therefore also aids in lowering blood pressure, helps the heart by having less fluid volume to circulate, prevents congestive heart failure and aids in getting rid of fluid.  If the cat develops CHF, or if the heart condition decreases so that CHF is a threat, then typically a cat should receive at least 5 mg twice a day.  More will be needed as the disease progresses or as congestion becomes a constant problem.

She took the following amount of Lasix (furosemide) as of November 2014 to December 2015: 25mg QID-four times a day.  From summer of 2014-November of 2014: 15mg in the a.m., 18mg at lunch, 15mg at 7p.m., 18mg at 11:30 p.m.  The cardiologist did not want to overload her kidneys with heavy hits of Lasix. But as CHF became constant, she needed a more consistent dose. Hence, the 25mg QID. 

We also injected Lasix when she needed it because the effect on congestion is quicker. Talk to your vet about this option.  (Myrna could not withstand multiple, daily injections because she developed horrible skin lesions. When had to stop during the summer of 2013 and use it only when needed. She needed it more in the last few months and we simply had to deal with the horrible lesions when they developed.We could never mitigate them. We used new needles each time; we cleaned the area before and after the injection with sterile meds; we even tried a new brand of injectable lasix to no avail.)

Torasemide-As of December 2014 she took Torsemide after developing pleural effusion.  She took 7.5mg once a day.  But that only until January when she developed congestion again, this time when lymphatic fluid or chylothorax developed in the pleural cavity.  The Torsemide was increased to 5mg in the a.m., 2.5mg around 3 p.m., and 5mg at 11 p.m.   By May she took 7.5mg QID.   Torsemide quickly depletes the body of potassium and can damage or decrease kidney function.  Because of this, a good vitamin source is necessary; additional potassium is necessary (Renal K gel and powder, Sundown Potassium tablets for example), and vitamins for kidney support (see the information below.)

Thiazide-Is good at reducing hypertension and decreasing fluid retention. While they can work alone, they are often given in small doses in addition to a loop diuretic Lasix or Torsemide to help the loop diuretic.  Loop refers to the part of a cell in the kidney that a loop diuretic affects while Thiazide affects the proximal portion of the distal convoluted tubule to prevent sodium resorption and promote potassium excretion in the diuresis process. 

7) She took 1/4  of a tab twice a day of Spironolactone-a potassium sparing diuretic.  Spironolactone competes with aldosterone at its receptor site, causing a mild diuresis and potassium retention.

8) She took a 1/4 tab of Isosorbide once a day in the evening.  It's a nitrate. It helps increase oxygen and blood to the heart by keeping blood veins opened; and the open veins reduce blood pressure.  It also redistributes the load from the heart (this one is difficult to explain and she was put on it to reduce the cardiovascular load to help ease her congestion. Your cat may not yet need this.) 

There are other meds some vets choose to prescribe which Myrna's vet does not:  

One is Carvedilol, a beta blocker like atenolol. The vet prefers Atenolol.  
Nattokinase, a soy based enzyme, which is used as a blood thinner but with limited results.  Plavix or aspirin is best.   
Aminophylline, a bronchodialator that opens up airways in the lungs when there is congestion.  This is an old method and should no longer be given to fight congestion in the lungs. It also raises the heart rate which is not what a cat with heart disease needs. Lasix should be used instead.  Aminophylline is best used for cats with asthma.

Pimobedan or Vetmedin was created for use in dogs with heart disease.  It was not approved by the FDA for use in cat but some vets do use it as does Myrna's.  We chose not to give it to Myrna. It improves the contractility of the heart but has potential side effects. 

Myrna took Albuterol for Asthma during the summer of 2014 until December 2014.  Once she developed chylothorax, she seemed not to need the inhaler.  During the summer of 2015, we kept the windows closed, thereby controlling air quality by decreasing irritants she could inhale; and by decreasing the heat and humidity that would come in from the outside. The mobile air conditioners were set on 72-74 (but not lower) in order to control air quality.  Hand held humidity and temperature control devices helped me monitor room air quality. 

Asthma is not common in heart diseased cats but can happen due to inflammation in the lungs.  And it can occur in cats which do not have heart disease.  For more information, check the website called Feline Asthma with Fritz the Brave.  Remember: cats with heart disease CANNOT use steroid based inhalers such as Flovent.  Use Flovent only with cats without heart disease. 


Supplements are necessary to replenish electrolytes and other vitamins and minerals that are removed due to the diuretics and to improve the condition of the body and heart function.  These are necessary for survival, for strength, for endurance against heart disease. Without replenishment, the body grows weak and is unable to handle the effects of heart disease. 

Many of these can be purchased at the grocery store, the pharmacy, pet stores, vets' offices, online pet stores, and Amazon.  That many of these links are linked to Amazon is in no way a support or an ad for Amazon.  Whether it is medicines or supplements or cat supplies, shop around at online stores, Amazon, and local stores and compare prices to find the most convenient to buy and affordable for you. 

1) To fight the chylothorax, she was taking 1/2 tab three times a day of 500mg of Rutin.  I should have tried other forms of Rutin. I did not comprehend the extent of damage the fluid could do to the lungs nor the ensuing complications of getting rid of congestion. Or perhaps there were other things that could have reduced the effects of chylothorax.  But I never concentrated on the chylorthorax enough and it was a contributing factor to her death.  Chylothorax is a lymphatic fluid that drains from the intestinal tract to the vena cava but due to heart disease, backs into the pleural cavity.  Rutin is thought to change the triclycerides in the lymphatic fluid so that it flows more easily to the vena cava and does not back into the pleural cavity.  It was suppose to change the makeup of the fluid so that it does not cause fibrosis-or scarring-in the pleural cavity. 

2) COQ10 is needed for heart health. Myrna received 200mg a day of Nature Made COQ10 which I mixed into her food after piercing the gel cap and squeezing out the oil.  I administered it this way for four years before adding it to the mixture for kidney support (see notes below.)  COQ10 improved her heart function.

3) Potassium is necessary for kidney, heart, and overall health. Being hyper (too high) or hypokalemia (too low) in potassium can often cause the same symptoms-lethargy, nervousness, vomiting, etc.  Potassium is mobilized to run the heart and is needed to create strong kidneys. The kidneys run the diuresis process and when a cat is on lasix, the cat needs more potassium. Diuretics promote excretion of fluid but in the fluid are electrolytes the body needs to properly function. One of these electrolytes is potassium.  A potassium supplement must always be given when the cat is on lasix and increased as the need for a diuretic increases. Myrna received four or more tabs a day of 595mg tabs of Sundown Potassium Gluconate that were cut into pieces and given by mouth.  We also tried to give her some of the 485mg tabs of Tumil-k potassium a day. But then her potassium level decreased and we resumed using Sundown.  In the summer of 2015, we began to also use Renal K powder in her food which worked when she was eating; or Renal K gel by mouth when she wasn’t eating.  I had also previously mixed a bit of banana into her food. When she stopped eating bananas, I mixed in sweet potato baby food until I began to use that as the base for the kidney support mixture. (See note below.) 

4) She received an inch of Petco cat vitamin gel.  (No link available.) A cat on diuretics loses electrolytes in the fluid that is excreted. Those are: magnesium, potassium, sodium, glucose, chloride, bicarb. A good overall vitamin paste will help get the nutrients it needs. A normally healthy cat should be able to get the nutrients it needs by eating regular cat food. But this is not the case for a cat on medications and diuretics.

5) She received one ml a day of Viralys brand lysine, an amino acid, to help fight the herpes virus she was exposed to as a kitten.  It is also good for the heart.   

5) To improve kidney function, to decrease BUN and creatinine, (two links about improving kidneys as they decline) I created a mixture that I gave to Myrna by mouth three times a day of one 3ml syringe.  This was a mixture of vitamins and supplements that she would not eat when mixed into her food and was easier to administer when mixed together as a solution. This recipe is per day. If you mix up more than one day's worth at a time, then multiple these amounts by number of days: one Solgar 100mg vitamin E oil, (any vitamin E you can pierce and that you trust will work); one Nature Made 200mg COQ10 (or any COQ10 you prefer); 2 tsp (or 10ml) of Gerber Baby's First Foods Sweet Potatoes;1/2 ml of water; a smidge of Halo vitamin C for cats; and some drops of Sundown Krill oil.  All gel caps were pierced and squeezed into a container, mixed, and syringed, and given orally. Later, I added in the dry Renal k powder. I found it easier if I mixed dry powders first, then added the water and mixed to dissolve, then added the baby food, then added the pierced gels and oils. Mix well each time you administer the solution.

6) She received 1/2 of a 500mg Nature Made B12 a day. Use any good B12 you trust. Vets often recommend injecting B12 but Myrna had issues with injections due to lesions.

7) She received 1/2 of a 325mg Nature Made Iron three times a day and I believe this was key to improving her kidneys once she was on Torsemide.  Torsemide is an incredibly strong diuretic but very difficult for the kidneys to handle. I believe that her kidney values remained stable after she began taking iron in the fall of 2014. But it creates a messy bowel movement. You may need to adjust the dose based on if it causes diarrhea or not; may also cause constipation. Give extra water by mouth if it causes constipation; decrease dose or use rice or bananas or rice water to stop diarrhea. 

8) She received 1/4 of a 250mg Nature Made magnesium twice a week.

For stomach issues I tried giving her 1ml of club soda twice a day.  Then I tried 1ml of apple cider vinegar, cut with water, by mouth each day. (Apple cider helps with both digestion/stomach acid and helps the kidneys.)  This worked until September 2014 when I had to switch to 1/4 a day of Pepcid because the stomach acid became too much for her to handle.  She began not eating well and had some vomiting issues. 

What About Pain Meds?

If your cat needs a pain medication, Buprenex or Valium are safe choices depending on the cat's heart health.  All other medications may not be safe because they may lower the breathing rate too far.   Cats with poor hearts cannot tolerate typical surgical anesthesia.  If your cat needs surgery, discuss with the cardiologist what the cat may be able to tolerate before proceeding with any surgery. 

Remember-HCM cats CANNOT have any form of steroids.


  1. Christine Saettone-NedbalApril 14, 2018 at 12:53 AM

    I'm so happy I came across your site. My baby boy Java was found with HCM and in CHF Feb. 24th this year(2018). I'm not happy with the current vet I have b/c they don't seem to be taking precedence of getting him out of CHF. I want to increase the lasix. At one point was the lasix too much that it was hurting Myrna's kidneys? Java is currently on 1.25 mg Vetmedin, 1.25 mg Enalapril, and 12.5 mg Lasix/Salix twice a day and 18.75mg pill of Plavix every night. Would love to hear your opinion! Thank you!

    1. If the cat is in constant or frequent CHF, then more lasix is needed. Good call. Sorry that your cat is sick and that the vet is not approaching it aggressively. It is a balancing act: support the HCM with many drugs to support and improve the heart function to help avoid CHF; increase lasix; improve health with vitamins and supplements; be as aggressive as possible but constantly monitor kidney function with blood tests and monitor the cat for how well it responds physically to the lasix and other drugs in both positive and negative ways. You can increase lasix and decrease it as needed; increase the dose for when CHF seems to be present, then decrease it slightly but increase the regular dose. So, if the cat began with 5mg a day of lasix, increase it to 5mg twice a day and then 5mg three times, etc. When CHF hits, you may need 10mg every 4 hours for a couple of days, then decrease it to 10 every 6 hours, etc. Those are rough examples. The cat needs lasix given throughout the day. Too much at once, and it's a hit to the kidneys and it leaves the body sooner. But a dose given throughout the day is a sustained dose, a sustained attack against CHF and easier on the kidneys. So-5mg at 7 a.m., 5mg at noon, 5 mg at 5 p.m., 5mg at 11 p.m.-as an example. Or 10mg in a.m., 5 mg afternoon, 10 in evening, 5 at bedtime, etc. Myrna's doses changed throughout her life. At one point, Myrna was on 100mg a day of lasix at 25mg a dose. But she also had a lot of kidney support supplements. To support the kidneys, give extra potassium. Use Renal K powder and/gel and we also used human potassium pills with those. Then I created the kidney support concoction of vitamin E, C, etc. and later added iron. Iron was difficult to give and hard on her gastro system but necessary to support the kidneys once the BUN was up in the 30s and the creatinine was about 2.7. But those values remained stable for the last year of her life. So, find iron for cats if you can or give small doses of the human form-we used pills. Use an overall vitamin for cats-paste or gel is easier to give. Protect the cat by keeping it calm, out of humid or cold air-no open windows at all, do not let it outside. Run portable air conditioner if you don't have AC in the home but don't let it get too cold or too humid-around 72 is fine. Stress, loud noises, rambunctious children-all create stress which raises heart rate which creates CHF for some reason. I hope this helps. You could find another vet. You will need to press this vet to work with you and not against you. But I suggest that lasix needs to be given throughout the day; and that you need to increase it when in CHF-and attack it sooner at home-by giving an extra 2-5mg at home every four hours and monitor breathing to see if the cat responds. To monitor breathing-count chest movements. One up and down is one count; how many of those in 15 seconds? 6 and the cat is fine; 8-10 that do not fluctuate and the cat may be in CHF. I always counted, waited five minutes, counted again then gave extra lasix if I thought it was CHF. Normally I could take care of it at home but if the breathing increased then we were off to the ER vet for oxygen and injected lasix. I hope this helps. Good luck!

  2. Christine SaettoneApril 30, 2018 at 11:46 AM

    I just saw this!!!! Vet called today...we're going to do 12.5 mg 3 times a day. When do you think we should get the blood work done again? Thank you!!

    1. Myrna saw her cardio every three months. So, the cardio ran blood work every visit; we would do them again if she ended up in the ER or if there was a concern even if they had been done that week already. It always gave us something to refer to and to see changes. When she saw the regular vet, we would do them if she was there for an issue or concern. I depended on them to tell me where her potassium levels were and how the kidneys and body functioned in general. You can learn a lot from blood including hydration levels.

  3. Christine SaettoneMay 3, 2018 at 11:41 PM

    We are also giving a potassium supplement..On my own five him coq10 and a feline cardiac support supplement from Standard Process. His breathing rate has improved so much...he was 48 to 52 he is at 38. What was your protocol?

    1. I do not mix my personal and Cat pages but you can message at the Cat Facebook page. However, I get messages from the blog posted to email faster than those from Facebook. Facebook messages get buried sometimes on the page or I get delayed notices. Not sure.

  4. For the breathing rate? Normal is 24 so I would not let it get about 28-30 before giving more lasix-after I made sure it was sustained and not just a fluxuation. For potassium-we gave her 595mg of potassium pills during the day as well as Renal K gel by mouth and I added Renal K powder to the kidney support mixture (discussed above.) Since she received blood work every three months, I could monitor the levels and adjust as needed. She also seemed to go out of the box if the potassium got too high so then I would give her Methigel a urine acidifier. It was like a see-saw and not easy to balance.

  5. Christine SaettoneMay 4, 2018 at 1:39 AM

    I've seen online that 20-30 is normal. So if she went over, how did you handle that? He's on Renal K powder twice a day. How soon did you test if the Renal K was enough?

    1. Cats' breathing rate will fluctuate. It helps if you have a healthy cat around with which to compare. You'll see that they will breathe 30-40 and then suddenly it's back to 24-30. Cats breathe fast when sleeping (from 24-40 and back), watching birds, playing, when feeling under attack by another cat, when anxious, etc. At rest breathing rate can take a few minutes to be revealed. To monitor, try to get the cat to rest and relax. Count the rate-one up and down chest movement, etc. See if it's high. If the cat is beginning to relax, count it again after a couple minutes. If after five minutes, the rate is still high, I would give Myrna 2-5mg of extra lasix-how much changed over the years due to how much she was already receiving. If she had already had her 5-10mg dose and seemed to be in CHF, I would give 1/4 or a 1/2 pill. It was a process that changed over the years, and she'd get more if the rate was 30 or more. After giving extra lasix, I would wait 20-30 and monitor breathing. If I saw it decrease, then I knew the lasix was working and I would continue to monitor until I saw that at rest, the rate was around 24 for example. If it continued to go up or the lasix was not working, typically I would take her to the cardio or ER. And usually I was right-she was in CHF. Other signs-Myrna would get anxious and let me know something was wrong. I would calm her, count the breathing, etc. If she was still anxious, then that corresponded with her breathing rate and it would usually be CHF so off to the vet we'd go after I also gave extra lasix. Signs of pain due to CHF-a look of distress on the face, inability to rest, or inability to be mobile because they are uncomfortable and breathing too hard. While all of these corresponded to high breathing rates and extra lasix, I also took her to the vet or ER vet immediately. I would give lasix and then tell them when we arrived exactly how much lasix she had had already that day. I'm sure it's a process that will be different with each cat. But Myrna was good at telling me when things were not right just in case I had missed something.

    2. Hi Joanne, Thank you for the info. It is very helpful. My cat Mochi is 7 years old and diagnosed with HCM. We have scheduled an ultrasound sound next Wednesday. Mochi has been taking fish oil, coq10 and cardio supplements daily. I’m thinking of giving him hemp oil daily. Do u have any recommendation of it? Appreciate your help in advance. Thank you~

    3. There's no benefit for HCM cats. Your cat's not in pain per se and it could be contraindicated to any other heart med, especially those used to lower the heart rate as the hemp oil would cause possible sedation. The cat should be placed on heart meds such as beta blockers-Atenolol, ACE inhibitors-Enalapril, blood thinner Plavix, and a diuretic to get rid of/keep away fluids that buildup and cause congestion-which for cats is deadly. I would see the cardio, discover the issues, and discuss heart meds with the vet; and discuss hemp with the vet. But I would not recommend hemp in general for HCM.