Dog on Pexion with severe dermatitis/otitis externa

RE: Dog on Pexion with severe dermatitis/otitis externa

Martin Atkinson — Wed, 01 Feb 2017 10:51:57 GMT

I've spoken to Boehringer and they have no reports of skin reactions to Pexion. The vet there advised keeping patients on present dose of Pexion until phenobarbitone has reached steady state then gradually reducing Pexion if you want to bearing in mind that it takes 3 days to clear.

RE: Dog on Pexion with severe dermatitis/otitis externa

Clive Ansell — Tue, 31 Jan 2017 18:39:21 GMT

They're prone to AIHA and AITP of course.

RE: Dog on Pexion with severe dermatitis/otitis externa

Beats — Tue, 31 Jan 2017 18:34:06 GMT

[quote user="Sarah Keir"]Is it a working cocker or show type? If the later then I'd be suspicious of immune-mediated skin disease too.[/quote]

do you have any more info or links on this? Is this a new "thing" or just a predisposition in the breed to familiar immune-mediated conditions such as pemphigus, drug-reaction etc?

RE: Dog on Pexion with severe dermatitis/otitis externa

Clive Ansell — Tue, 31 Jan 2017 17:51:20 GMT

If skin isn't resolving with Apoquell, and infection and parasites have been excluded -maybe switch to a short course of immunosuppressive prednisolone dose?

Unsure about how to switch form Pexion to Phenobarbitone, my hunch would be to get on therapeutic Phenobarbitone dose asap, and gradually reduce Pexion over 2-3 weeks, maybe a month.

RE: Dog on Pexion with severe dermatitis/otitis externa

Robin Grimmer — Tue, 31 Jan 2017 17:32:41 GMT

[quote user="Martin Atkinson"]

[/quote]

There is a protocol for switching over to Pexion from Epiphen so presumably there is one for switching the other way. Maybe speak to Vetoquinol?

RE: Dog on Pexion with severe dermatitis/otitis externa

Martin Atkinson — Tue, 31 Jan 2017 17:30:44 GMT

[quote user="Clive Ansell"]Or if other causes have been excluded, switch to Phenobarbitone, stop Pexion, and see if skin resolves?[/quote]This is exactly my thoughts. Would you stop the Pexion straight away or wean her off? Either way is not ideal as the phenobarb takes a while to cut in and she was having several fits a week but if I keep her on Pexion for several days the skin may not resolve. Dilemma.

[quote user="Sarah Keir"]Is it a working cocker or show type? If the later then I'd be suspicious of immune-mediated skin disease too.[/quote]She's a 'show type'. The locum has put her on Apoquel while I was away last week, I'm a bit scared to try any more immunouppressive drugs while the skin looks infected although the lab results say not.

RE: Dog on Pexion with severe dermatitis/otitis externa

Robin Grimmer — Tue, 31 Jan 2017 17:30:42 GMT

I had one case that I switched over to Pexion that did really well on the lowest dose of 10 mg/kg but generally haven't found it to be as reliable as phenobarbitone. If it's not working that well on the highest dose and you are possibly having side effects then time to change! Would a drug related problem even show on a biopsy? I agree, just switch over and see if ears (and seizures!) improve.

RE: Dog on Pexion with severe dermatitis/otitis externa

Sarah Keir — Tue, 31 Jan 2017 17:24:09 GMT

Is it a working cocker or show type? If the later then I'd be suspicious of immune-mediated skin disease too.

RE: Dog on Pexion with severe dermatitis/otitis externa

Clive Ansell — Tue, 31 Jan 2017 17:19:13 GMT

[quote user="Kara Gibson"] I'd recommend biopsies and talk to tBoeringher about it.[/quote]

Or if other causes have been excluded, switch to Phenobarbitone, stop Pexion, and see if skin resolves?

RE: Dog on Pexion with severe dermatitis/otitis externa

Kara Gibson — Tue, 31 Jan 2017 17:02:33 GMT

I've not had a case like this with Pexion but did have a dog on potassium bromide develop a presumably drug induced pemphigus foliaceous. I'd recommend biopsies and talk to tBoeringher about it.

RE: Dog on Pexion with severe dermatitis/otitis externa

Clive Ansell — Tue, 31 Jan 2017 16:49:09 GMT

I've come across many cases, including many on maximum dose, and never seen a skin reaction.

Finding that its not particularly effective, many cases are being switched back to or onto Phenobarbitone, which I tend to use first line anyway.