Paracetamol and NSAIDs

RE: Paracetamol and NSAIDs

Gwen Covey-Crump — Tue, 20 Oct 2020 12:42:56 GMT

Thank you, Lizzie, I apologise for being a little out of date and giving misinformation to the forum. It is good that Dechra have brought this datasheet up to date. Of note for the readers - Pardale is now a POM-V where previously it was NFA-SQP meaning pet owners could previously go and buy it from a pharmacy or online pharmacy without a prescription.

RE: Paracetamol and NSAIDs

Lizzie Barker — Tue, 20 Oct 2020 09:49:54 GMT

Hi, although not a specialist I work as the Anaesthesia and Analgesia Manager at Dechra EU. I thought that it might be helpful to let you know that the Pardale product SPC has recently been updated (December 2019) from the previous version correctly mentioned by your colleague.

The updated SPC now more accurately reflects the current understanding that paracetamol is not a classical NSAID, as described by Gwen, and the previous contraindication 'do not administer other NSAIDs concurrently or within 24 hours of each other' is no longer present.

You can access the updated SPC via the VMD website: https://www.vmd.defra.gov.uk/ProductInformationDatabase/Default.aspx or via request to the Dechra technical team: https://www.dechra.co.uk/contact/customer-services

I hope this is helpful and reduces confusion.

Best wishes, Lizzie

RE: Paracetamol and NSAIDs

niamhjl — Mon, 19 Oct 2020 21:19:23 GMT

Thanks Gwen, that’s really helpful. I too have always used much lower doses than the pardale data sheet, so I will continue this!

RE: Paracetamol and NSAIDs

Gwen Covey-Crump — Mon, 19 Oct 2020 15:54:42 GMT

Hi, I and many of my specialist colleagues are routinely using paracetamol (pardale or unlicensed form depending on availability and needs of the patient) alongside NSAIDs as part of a multi-modal pain management programme. Traditionally paracetamol was classed as an NSAID since it has some limited anti-inflammatory action and it is not a steroid. The licence for Pardale was extended over many years and the datasheet has not been changed. However, it is widely accepted that paracetamol works mainly via a different mechanism and should not be classed as a classical NSAID. There is some concern that use of paracetamol together with NSAID can make the kidneys more vulnerable due to an additive effect on prostaglandin housekeeping functions. However, in a well hydrated, normovolaemic dog with normal blood pressure and no renal or liver issues the consensus is that it is 'safe' with the caveat of not having a robust evidence base. However, many of us would avoid the combination during anaesthesia where hypotension may be a risk. We generally feel the pardale datasheet doses licenced fo 5 days are a bit high to be used at the same time as an NSAID and certainly too high for routine use long-term (more than 5 days). The concern is over depletion of liver enzymes required for the non-toxic metabolism of paracetamol, especially in older, dogs. In humans, liver toxicity can be insidious and difficult to detect until it is too late.

I usually dose at 10-15mg/kg TID (BID is often ineffective due to paracetamol's short half-life) but this may not be analgesic in many dogs. Many of my colleagues will happily use doses up to around 25mg/kg TID if the patient needs if for analgesic effect. My preference is to use the lower doses as a routine and allow the owner to give higher doses for a limited time period during a flare-up. We have no long term toxicity data so it is always wise to counsel the owner to the slight unknown risk and even individual variability in metabolic function. Keep an eye on liver and kidney function via regular blood haematology/biochemistry and urinalysis. Beware of situations where a cocktail of drugs is in use with an unknown effect on liver metabolism, in particular, dosing with CBD by the owner without the vet's knowledge comes to mind.

You might find this Veterinary prescriber module useful www.veterinaryprescriber.org/.../paracetamol-but-not-in-the-way-we-need-it

I hope this is helpful, hoping my colleagues will also chip in here.

Gwen