Hi Barbara, welcome the the site. Have you tried these capsules with your cats? Please share some detailsā¦
Any luck finding a vet who will prescribe rapamycin/sirolimus for a cat? I too have one in early days of CHF. Heās stable now but it has definitely progressed.
You may want to print out a copy of the RAPACAT study, highlight the significant parts, and try to convince your vet to read it. Trivium Vet, who completed the original study, is currently recruiting cats that are subclinical, for a year long trial of the medication.
A YouTube presentation on rapamycin for cats.
I did see this, thanks. In fact, finding this study is what led me here eventually. One question I have is whether or not there are any patients who shouldnāt take rapamycin. For example, if a cat has an arrhythmia known as āventricular premature contractionsā, does this mean the cat should not take this medication? Put another way, setting aside the immunosuppressant nature of the medication, could rapamycin make a cat worse or, tragically, could rapamycin be fatal whether directly or indirectly? Those of us committed to the principle of ādo know harmā while also wedded to the idea we have an inherent duty to save the lives of those in our care, whether family or not, can easily feel torn and/or conflicted; at least, I know I do.
My cat has been on 1 mg every ten days for the past couple of months (I just matched her to my schedule). I put one tablet in some flaked tuna. She wolfs it down. She seems to be tolerating it just fine. If anything, she snoozes more for a day or two after, but my guess is thatās just me being more aware of her behavior.
0.5 mg pills are available on Indiamart as well.
Who did you get them from? I canāt find anyone who sells them
I have not used these capsules on the cat yet, but I did the two hour vinegar test. I only used apple cider vinegar because thatās all I had, but the capsules did not dissolve. This is really important, because stomachs of cats and dogs are more acidic than humanns.
Edit: removed Indiamart sources for 0.5 mg pills. Iām being told itās currently unavailable.
I think many owners who are aware of Rapamycin for HCM cats are facing this dilemma. There are many drugs that have done very well in trials, that caused serious or even lethal, side effects to a small group of people after they were widely prescribed. It seems to me that if you are worried about an HCM cat that is subclinical and stable, maybe waiting for the results of the one year trial that Trivium is conducting, with regular echocardiograms to make sure that the condition is not progressing?
I think at this point, Ramamycin for HCM is something of a āHail Maryā. If they throw a clot, or things progress to CHF, thereās not much that can be done for them, other than to try to keep them comfortable. And the progression of this condition can be so variable. I wish that I had more answers.
Admin, do you know any studies that link rapa with coordination issues?
My cat is on rapa for nearly a year now. His scan results are added above and soon we will have the next scan, so i will update it. He is doing ok atm symptom-wise. He has a good appetite, normal activity level, good mood, not visible signs that his comfort of life is diminished. We do everything together, as always. After first 6 months on rapa the illness progressed, and his heart is more remodeled, and yet the dynamic slightly improved. But something worries me greatly. My cat has always been super agile. Jumping from any place to any place, never making the slightest mistake. He never knocked anything down (other that purposefully). He always had incredible sense of balance. In the last few weeks he started to make mistakes. He jumps on the desk and the jump is too short. He fell down a few times like this (not a serious fall, he landed on four and nothing bad happened but he did not jumped successfully). Immediately after he jumps again and all is fine. But he did it a few times and today he misjudged the distance between shelves by far. And I mean by far. I will say it again -it NEVER EVER EVER happened in the past. His eyesight seems to be ok - he can notice a snack from far away without a problem. We go to the vet on Saturday but I am trying to find a clue. Is there anything about rapa than could be linked to this? I cannot find anything. And I start to be seriously worriedā¦
No, Iāve never seen or heard of anything like that. It may just be a co-incidental issue that is developing. If it was my cat, Iād pause the rapamycin and see how things progress.
He is still asymptotic, good appetite, good quality of life, playful, active. Blood tests done today, biochemistry and TBC - all perfect. Awaiting the referral for his next heart scan now, should happen later in December or in January. But we had a very quick look at his heart today an no major HCM progression was visible. But my vet is not a cardio, so that was not very detailed.
So after a discussion with vet where we penciled out as many possibilities as we could think, of, and eliminated many, but not all, we decided to keep rapa and add solensia in case it is an early arthritis case (he jumps, feels pain and aborts). I will administer him a second dose next month and we will observe if it helps. if not, we will get a referral to a neurologist. will keep you all updated. PS he is jumping ok 98% of time, it is just that he suddenly sometimes makes mistakes. PS2 his kidney parameteres has never been that good. 
Kevin Toman, DVM
I emailed him, and he was very nice, but said that he doesnāt himself prescribe for cats. This was in early December, so I donāt know if thatās changed. Also, he prescribes through a compound pharmacy, and he mentioned the problem with no cat size (#3 and #4) enteric capsules.
He will, however, help you get a prescription if your own vet is willing to prescribe.
I am very new to the world to rapamycin, but hope others can chime in on whether breaking a 1mg sirolimus tablet and placing it into the delayed release capsule you posted would be an option.
Iām thinking about this option. If I go according to the RAPACAT study, my 12 lb and change cat would require 1.5 mg on the low dosage. (.3 mg/kg). The other option would be to dose 1mg of sirolimus, and .5 mg of everolimus. However, everolimus was not used in the RAPACAT study, and I have no idea how everolimus would work on a cat, or if itās even safe for a cat to take.
Most scientists and clinicians Iāve talked to say there is no functional difference between rapamycin and everolimus.
As far as dosing you could also dose a little under one week, and a little over (higher mg/kg) another week, so the average is the target dose.
There is a wide variation in dosing levels that have been investigated in dogs and similar mammals. The optimal dosing is far from being determined, so its all somewhat a guessing game right now (or trial and error).