There's a product a breeder friend of ours had us use that works excellent and can be purchased at most feed mills. It is generally used to treat horses or cattle. It is called 'fenbendazole' and is sold under several trade names such as; 'panacure - safe-guard etc...' For the product I have which is in a 100mg/g tube, you utilize 25mg for every 1000gr of snake. For my 70 gram ball python for example, I mixed one 'notch' (25mg) of the tube of medication with 30cc of distilled water and injected the mice at the dose rate of about 1cc, I administered this on 2 occasions, each dose worked out to approximately 5mg. This worked wonders for her, she started to gain weight right before our very eyes and her skin tone became silky, where it was very rough and dry, her stools became of normal color and consistency. Whatever you do, tell the feed mill folks that you are purchasing the product for horses or cattle (this depends on which tube you purchase) this way, you are not taxed for it.
On the external parasites, Seven Dust at 5% concentration is what I use on 'all' my animals except the bird. I haven't had to use it on the snakes as yet (knock on wood), but if you do, dust the bottom of the cage with a thick coating and let them crawl around in it. Of course remove the water during the process but dust all their hide boxes and such. I've been told to leave this overnight and then give the cage a good cleaning and disinfection process afterward. There are several products on the market for snakes for external mites but I'm leary of all of them except "Black Knight" which we used in the store where I used to work, without incident and it worked gang busters. So if you're like others and scared of Seven, use that instead. But the truth is, I've gotten Seven dust all in my own mouth and nose when using it in kennels and it never hurt me, I can say the same for the animals, they lick it off and you never see any signs of damage physically or psychologically, or at least I never have. I've used it with great results.
I hope that helps,
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