Ivermectin should work if it's a pest that gets to the bird's blood. some pests only eat feathers, skin dander, etc, but don't get actual blood. For the non-blood, try permethrin dust or spray. For the blood suckers, I use ivermectin drop-on (goes in thru the skin, just like your dog's flea drops). I get it at
Tractor Supply in a big bottle (pour-on for cows). They also sell syringes, so I buy several small ones (no needle). I suck the ivermectin into the syringe(s), put them into a plastic baggy and carry that to the coop (usually around 4 am). Nuzzle the tip of the syringe down into the feathers so you get the stuff onto the skin (wear gloves if you don't need a dose yourself!). Squirt it onto the skin, usually between the shoulder blades, but any skin will do--some put a drop or so at the vent for mites there. I usually use 4-8 drops per bird (more if bigger, less if smaller birds). Someplace on here has the mls/pound.
IF you get some on yourself, wash soon. It is used for parasites in humans, so a drop or so won't kill you. IF you overdose your birds (like I did the first time--by a lot, math challenged), it should be okay. Mine were, just a bit runny poops that day.
I think standard withdrawal for eggs is 14 days and don't feed them back to the chickens (what medicine is in the eggs will go the the eater). I don't give away those eggs to friends, but I do eat them myself (and DH). I don't think I'd get a big enough dose to worry about.
Also, I think it's standard to re-treat the birds in 10 days. This gives any eggs time to hatch but get killed before they reach the age to reproduce. If your birds have a heavy worm load, you may want to treat with wazine first because huge amounts of dead worms (killed by ivermectin) can cause problems. Wazine will gently kill a bunch and then the ivermectin a week later gets the rest.
As with all chemicals, be careful. don't over or under apply. don't get dosed yourself. Safely dispose of packaging, etc. I have washed and reused syringes, but they are fairly cheap.
I hope this helps you. Sorry for not getting the exact doses for you, but it's in the site somewhere and I'm sure you're reading up on it.