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Nexgard flea treatment making my dog very unwell


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I have a 2 year old whippet and all his life he has been having episodes of nausea, vomiting (bile normally), loss of appetite, diarrhoea. Also other odd symptoms his behaviour has changed lately, now becoming a bit dominant around other dogs, also he itches and sometimes trembles when lying on the sofa.

The episodes last a few days and normally self resolve. I have been to the vets several times and each time they say there is nothing obviously wrong and always try and send him in for expensive tests or prescribe extra medications.

i have tried every type of expensive food and probiotics and any change in diet seems to work for a bit then he reverts back. Having done my own research all his symptoms are well known side effects of Nexguard worm treatment. I said this to my vet and she had to look up the side effects.

I am medically trained and a prescriber for humans so have some reasonable understanding. It is common practice to review medications when assessing and minimise extra medicines and invasive tests wherever possible.

Although it is going to take a few months of using a different medication to see if this is the cause, however reading various articles, forums and journals I am convinced this is the cause. I have lodged a complaint with the surgery.

My question, Is this negligence?

In medicine prescribing a medicine without the full knowledge of the drug, its interactions and side effects would be. So would prescribing a medication and not explaining risks and giving the patient full informed consent. When reviewing a patient and not completing a thorough medication review and trying an alternative medicine would be.

Wonder if any pet owners have had similar experiences? Any vets on here that can give me your perspective?
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I really hope this is the answer to your whippet's troubles. I'm wondering, if he may be generally sensitive to a range of medications, would it be worth trying using natural flea prevention for a while (or just keeping a close eye out and only treating if you see evidence of fleas) rather than switching to a different treatment?

You may be well ahead of me here, but I think there are two questions here: (a) is this negligence, and (b) if so, what action do you want to take? Do you simply want to ensure that this doesn't happen to another dog, or are you hoping for compensation? I imagine the latter could be very tricky indeed.
I’m not bothered at all by compensation. Maybe a refund on the last few hundred quid of pointless tests. It’s more that they recognise the failure of the process and put some changes in as well as investigating the effects on other dogs in their care
Also Judy, had to edit my original post for a typo, nexgard is a worm treatment not flea
I think Nexgard does worms and fleas/ticks etc.

Not that that answers your question.
Do please let us know their response to your complaint - I hope it achieves something. Have you come across Wormcount or similar companies? You send them a stool sample and they check it for worms, so you only have to treat if your dog is infected. I used it with my dog and can thoroughly recommend it.
You have mentioned "Diet" and that you have tried many types of "expensive" foods.
"Expensive" is not always the best ! And I wonder if you have given your change of foods each a fair trial, with time for positive results.
What type and make of food are you feeding at the moment?
Have you considered a "Homeopathic" vet who may possibly be able to help with less medications and drugs.
Prescribed medication and drugs are not always the best "Golden answer".
You have self diagnosed the "Next Guard" as the culprit , Are you a vet ?
There may be some other underlying reason for your problem.
Have you tried as mentioned by @JudyN , trying a natural remedy or only treating fleas when you see them. The same with worming, and have a worm count done, and only treat the worms, if any, with an appropriate drug.

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