Poultry Talk Ontario (pto.ca)

What type of Ivermectin works again, externally? Pour on? What’s the dose for bantam birds? Does anyone still eat the eggs? What can I treat the coop with - will bleach work? I’m burning the roosts.

for leg mites i use pour on right on the leg scales and rub it in. wear gloves or you will get dosed with ivermectin too! for my standards i use 0.75 ml putting about 0.25 dropped on the bird, and then 0.25 on each leg. and rub it in through the scales. for a bantie the dose will be much less than that-likely 0.5 ml for the roosters for the entire dose...then split that between the drip on and rub on the legs.
some people will also smother the mites by smearing vegetable oil on the birds legs to seal them in, or vaseline. i found this is a great way to get one super dirty bird super fast.....but it also apparently works, but you need to reapply daily....where the ivermec you do day 1 and day 10.

Yeah, what @WLLady said. You can use Ivermectin externally; the pour-on stuff is what most recommend.
I found what worked for me was two applications of Ivermectin topically, between the shoulder blades (or whatever they're called on chickens), 7 to 10 days apart. I also cleaned off their legs, then liberally slathering VetRX onto them, and reapplying regularly until after the last Ivermectin treatment. Others use Vaseline, cooking oil, coconut oil, or any kind of oil, really - same basic principle: suffocate the buggers! I used VetRX because (a) I had it, and (b) it's got other ingredients that promote healing.
As for the roosts, I cleaned and disinfected the roost bars, then applied Neem oil to them as well and let it soak in. Again, any oil will work if you don't have Neem oil. My roosts are unfinished 2 x 3s.
I also replaced the coop bedding.

Just curious do you need to withhold eggs when using ivermec externally?
Cheers Karen

OK so don't shoot me but I eat the eggs when I use Ivermectin. It is used under special clearance for parasites in humans on occasion. I don't sell them though.

You don't sell what? Parasites? Humans? Please try to be a little bit more articulate.

Well mostly the eggs but I may pass on a few parasites for free if you know me reeeeeeelly well!

If its OK, I will pass on them too.

..but in a weird way....

Scaly leg is simply awful. When I first discovered my birds had it, they'd already had it for years, and I passed it off as normal, because all the hens that obviously had it were old. I thought it was just something old chicken scales naturally did, when in fact, it just takes time to show the ugly damage. By the time you see lifted scales, they've been there a year. White crusties, two years or more.
I tried the Vaseline daily, Vicks vapor rub daily, cooking oil infused with oregano and peppermint. I scrubbed, picked, peeled and oiled for months with little improvement. THEN I found out that with a severe, chronic case like I had, even if the mites were long gone, the legs scales would not look normal again until they fell out and regrew. If heavily diseased, you can soak and scrub the worst of them off, but some ugly scales will resist until they moult out. I also found out that the microscopic bugs are everywhere, and even if you burn the coop down, they'll just move into the new one. You cannot completely eradicate them, only control, and ivermectin does the trick.
I went through a boatload of trouble for nothing. Now I just ivermectin everyone twice a year. It kills various parasites, including cecal worms, which is important for me because I also have turkeys and the blackhead parasite.
I personally have no qualms about eating eggs from treated birds, but mostly, the week after treatment, I set them for hatching. I use pour-on, applied with a syringe (no needle). I lift a wing and drop the stuff on bare skin. It has to touch bare skin and be absorbed (or ingested by the bird) to work, and under the wing close to the body is very bald and very vascular. It has not EVER, in my experience, irritated their skin in any way, nor caused any problems if I accidentally squirted WAY too much while dealing with a struggling screamer.