Cushings Vetoryl Blindness

[Dato]

Hello,
Let me introduce my dog, share some info and ask some questions.
Megan is 12 years old dachshund , regular size, 20 Lb

First signs of cushing’s started when she was 8 : panting and looking for cold place.
We used Curcumin supplement for 2 years and there was no panting or other symptoms.
Curcumin was helping but not as cushing’s drug but as general tumor slow down remedy.
When she was 11 panting came back. Also her head started trembling especially after yawning.
Crazy appetite but not drinking much. Hair shown huge grows.
Legs trembling , no energy.

We started Vetoryl in the begging of December 2023 after doing low-dose dexamethasone suppression test.
10 mg /day dosage
I was able to see improvement in dogs condition but she got bloodshot red eyes. I saw it for first time.
We did ACTH in end of December 2023 which shown Cortisol Baseline 188, Post ACTH 306 nmol/L
Vet suggested to keep dosage.
In Jan 2024 dog became bad again: foggy eyes, veggy condition, no interest to life , became almost deaf.

Vet increased Vetoryl dosage to 20 mg. More days with bloodshot red eyes.
At end of January dog is almost blind.
We started glaucoma eye drops Dorzolamide , at least vision degradation stopped on “almost blind”

I was giving her 20 mg for 1.5 months then did another ACTH which shown Cortisol Baseline 42 Post ACTH 35

Also elevated in recent blood work:
Urea 11.5 Albumin 44 ALT 181 ALP 1776 Lipase 2436

Vet asked to stop giving Vetoryl for one week
No red eyes anymore

So question is :
Was her bloodshot red eyes and blindness even caused by high cortisol level or that was caused by Vetoryl?

Also has to mention dog have heart failure , so she is getting Vetmedin \Torsemide (furosemide before)\benazepril trio all that time.
Doing research shows that Furosemide could cause deafness but I cant find any confirmation that those drugs can cause blindness.
Thank you all !

[labblab]

Welcome to you and Megan — I’m really glad to see that you’ve been able to log in and post! I’ll come back again tomorrow when I’ll have the time to write a more complete reply. But I didn’t want to waste any time in reassuring you that your membership has been approved and that you are posting in exactly the right place.

So once again, welcome. And I’ll be “seeing” you again tomorrow ;-).

Marianne

[labblab]

Hello again. I'm surely sorry that Megan is doing poorly right now. Thanks so much for the information you've given us already. Out of the things you've written, the thing I'm most worried about is the result of the most recent ACTH test. If I'm understanding it correctly, the test was done after around six weeks after the doubling of her Vetoryl dose from 10 mg. to 20 mg. daily. Here are the results of that test:

Cortisol Baseline 42 (this converts to 1.5 ug/dL for our readers who are more familiar with this reporting unit)
Post ACTH 35 (this converts to 1.2 ug/dL)

This result is definitely too low, and it seems especially worrisome to me that the second, stimulated reading is even lower than the baseline reading. Megan may need much longer than just one week in order for her adrenal function to rebound. I am not a vet, but I don't believe it's safe to restart the Vetoryl at any dose until you have test results that confirm that her cortisol is once again abnormally elevated, along with a return of observable Cushing's sympoms. Some dogs take weeks or even months to rebound after their adrenal function has been oversuppressed by the medication. And during that time, they may even need to take supplemental prednisone to make up for the lack of natural cortisol production. So over and above anything else, I would not feel comfortable restarting the Vetoryl after only one week without followup testing, even if it is at a reduced dose (and certainly not again at the 20 mg. dose).

Backing up to a couple of your other questions, I know that some medications can cause deafness in dogs. I'm not aware of it ever being reported as a side effect of Vetoryl, however. I'm also not aware of red eyes being associated with the drug, either. I know allergies and infections can cause red eyes. Another thought that occurs to me is to ask whether Megan has ever had her blood pressure tested. Cushpups are vulnerable to developing high blood pressure, and hypertension can cause visible redness as well as hidden retinal damage that can lead to blindness. Blood pressure may not be any issue for Megan, but I thought I'd at least mention it.

There is another condition called "SARDS" that can cause rapid blindness in dogs, and it sometimes occurs alongside Cushing's. I'll go back and find some references to this disorder that I can give you. So I'll come back again once I have that info -- stay tuned!

Marianne

[labblab]

OK, I was able to come back more quickly than I had thought with at least this brief amount of information. Over the years, we have had members who joined us after their dogs suddenly went blind after having received a Cushing's diagnosis, or while exhibiting symptoms that are also common to Cushing's. For a few of these dogs, SARDS has been diagnosed.

SARDS ("Sudden Acquired Retinal Degeneration Syndrome) is a disease of unknown origin that causes sudden blindness in dogs, along with certain other symptoms that overlap with (and can be confused for) Cushing's, including excessive thirst, urination and hunger. Like Cushing’s, SARDS may be related to abnormal levels of adrenal hormones. Some dogs with SARDS actually test positive for Cushing’s, however others do not. The possible relationship between the two conditions remains poorly understood, Here’s an article that will tell you more:

https://vcahospitals.com/know-your-pet/sudden-acquired-retinal-degeneration-syndrome-sards

Interestingly, I read elsewhere that red eyes can bd a symptom of SARDS:


Clinical signs of SARDS include a sudden decline in vision or blindness, occurring within days to weeks; conjunctival hyperemia (red eyes); and dilated pupils.

Unfortunately, there is no known treatment for SARDS. And it's probably unlikely that this is Megan's problem, anyway. But I wanted to at least give you the info to consider.

Marianne

[Dato]

Hi Marianne

Thank you for your answers.

I will wait longer with restarting Vetoryl. The only problem is that dog also has CHF and symptoms are very similar like panting and high rate breathing
Sometimes it seems you need to increase the dosage of diuretic but then you realize it was cushing’s panting as her breathing rate become normal itself in hour.
With CHF it will not probably to return to normal until you increase the diuretic dosage.

Blood pressure was OK when we measured at clinic. Also Vetoryl , Torsemide and Benazepril
That she has been taking , all of them lower blood pressure. So recommendation is not to take them at the same time.

But that does not mean that intracranial pressure is normal.
And that tumor in her head that causing cushing’s it may press eye nerve as well.

Right now saving what is left from her vision is my biggest priority.

I actually found mentioning of cushings and bloodshot eyes relation on this web-site when I was googling problem
https://www.k9cushings.com/forum/showthread.php?3638-Can-cushings-cause-red-bloodshot-eyes

Nothing else on internet.
So looks like it is not happening to often and not Vetoryl related

Thank you!