Invermectin toxicity

[Vgirl]

Hi, could anyone advise me around the use of invermectin 1% and how safe this product is? I’ve been using this treatment by Naqua and the guidance is to use 1 drop to 500mg body weight. It is a 10mg/1ml solution. So for my 1.8kg hens, I’ve used 4 drops and for my turkey, who was 5kg, I used 10 drops. All seemed to tolerate their first doses, however after the second dose, one of my hens became quite lethargic the next day, vomited and had an impacted crop. Both hens had some black stools. My hen was seen and treated by a vet, who seemed to think the issue was down to her being ex commercial and she is now fine. More sadly, my turkey, who was the only one to receive a third and final dose, became very ill the following day after treatment and was unable to lift her head, was extremely lethargic, struggled to walk - so was immobile, she was panting, refused food and at times her body seemed to go completely rigid, including her legs. She was taken to a vets who couldn’t confirm what the issue was, but suspected ‘a bug’, but unfortunately gave her a poor prognosis. At this time her mite treatment wasn’t mentioned, as unfortunately it wasn’t myself who took her to the vet. She was given an antibiotic and steroid injection, which seemed to help a little, as she began to drink for herself (she seemed to be incredibly thirsty), however none of the above symptoms subsided. Unfortunately the next day, she collapsed on her back and vomited a huge amount of brown fluid. I managed to upright her, only for her to vomit a lot of brown fluid again, which I believed caused her to aspirate and die.
After reading up on invermectin, I am starting to wonder whether she was experiencing toxicity and overdose symptoms. At my guesstimate, 10 drops (0.3mls) is around 3mg of invermectin. Is this too much for a 5kg bird? There is no mention of toxicity amounts and overdose risks in the information leaflet provided and I am often seeing poultry owners recommending 1% invermectin as a mite/worm treatment in forums, which is the only reason I used it.
What are people’s thought? Did I just accidentally kill my girl?

 

[Kiki]

I would bet there was much more going on with your birds that caused them to be sick and the ivermectin had nothing to do with it.
Mites alone can kill birds quickly.

 

[Vgirl]

I would bet there was much more going on with your birds that caused them to be sick and the ivermectin had nothing to do with it.
Mites alone can kill birds quickly.

To be honest, I was treating them all more as a routine rather than concrete evidence of mites. My turkey girl seemed to be preening a lot and was leaving dry skin everywhere she went. Her head was dry and flakey and her legs looked as if she may have scaly leg mite, so hence I decided to treat her. Obviously I now wish that I’d researched invermectin more thoroughly, as had I known about the risks of toxicity and OD, I never would have used it.

 

[Kiki]

To be honest, I was treating them all more as a routine rather than concrete evidence of mites. My turkey girl seemed to be preening a lot and was leaving dry skin everywhere she went. Her head was dry and flakey and her legs looked as if she may have scaly leg mite, so hence I decided to treat her. Obviously I now wish that I’d researched invermectin more thoroughly, as had I known about the risks of toxicity and OD, I never would have used it.

Again I repeat it is highly unlikely you overdosed them with it.

 

[Eggcessive]

Sorry for your loss. I have no idea if the dosage is what killed them, but here is what I know about ivermectin for chickens: dosage of the 5 mg per ml is 0.1 ml for each 2 pounds of weight placed on the back of the neck over the spine. Dosage is only repeated once in 10-14 days. Since you used the 10 mg per pound, dosage would be 0.1 ml for 4 pounds, or 0.025 ml per pound. A 1 ml needle-less syringe can be found at most pharmacies if you ask, and most times they are free for animal or baby medicines. I don’t recommend giving ivermectin or any other med unless you see the mites on them.