mange mites

Question
Dear Dana

My bunny Nut， who is 2 years-old, has itchiness, redness, hair-loss. I took her to the vet, and the vet help had a scraping and fur, and then had a glass slide check, but he couldn't find any parasite or eggs. The vet thought it was mange mites, and prescribe 3 Doses Pfizer revolution(0.25ml potency:60mg/ml). After the first dose, Nut's scratching decreased, and her head and back, where lost hair, have many flaky skin peeling off, and the red spots disappeared. But it seems it didn't work after she had the second and third doses (all her articles for use have been cleaned and disinfected). After the second and the third doses, she still have red spots, hair loss and itchiness. At first ,the system only appear on her head and back, but after the second and the third doses, the system spread to the edges of the eyelids, back leg and her tail. I took her to the vet again. The vet made her had a ivermectin injection. And he said the after Nut lossing her hair, it's pretty easy for bacteria to invade, then he prescribe virbac allerderm for her to protect her skin. But after using the virbac allerderm for 2 hours, Nut's skin and ear became red and swollen. She kept scratching and grooming, which made her lost much hair of her right ear. After 48 hours, the redness disappeared. During this time, Nut didn't lost her appetite. Is virbac allerderm suitable for bunnies? What's the side-effect of ivermectin for bunnies?

Two days after the injection, Nut's redness disappeared, but still had many flaky skin peeling off and hair loss. If this normal?
   
Nut weighs 2kg. The vet prescribe 0.5mg ivermectin, but I read from the internet that the dose of ivermectin should be 0.4mg/kg. What 's the right dose of ivermectin？ Does the ivermectin (SC) has the same effect with the  ivermectin (PO)?

Does selamectin last longer and be more effective than ivermectin? Why Nut didn't turn better after using it?

I am in Asia, and the knowledge and skills of treating bunnies is limited. I printed your article(http://www.bio.miami.edu/hare/furloss.html) before I went to the vet. They didn't know that Pfizer - revolution and ivermectin can treat bunnies until they read your article. I desperately need your help.


tammy

Answer
Dear Tammy,

It's normal for a lot of sloughing and peeling to occur after the mites are dead.  The dose is adequate if the mange crusts slough off and the skin underneath begins to heal.

Selamectin does last longer than ivermectin, but I'm not convinced it lasts as long as the package says it does.  We've had to re-apply every *two* weeks, not four, to control some mites.  And I'm not a big fan of topical meds if you don't need them.

Keep an eye on Nut's skin for a couple of weeks.  If the peeling and flakes are still not gone, he may need another dose of Revolution.  We use 6-10mg/kg, which means 0.1ml of the 60mg/ml solution (small dog/cat/kitten) per kg of body weight.

I hope this helps.

Dana