Please do not give him another dose of spot-on - it is a topical treatment that is ineffective against sarcoptic mange and would mean he will have to wait a further week before he can have the treatment he really needs which is doramectin or ivermectin injections - a course of 3-4 at weekly intervals. Also please post up the mds you have used as it may affect the information given below.
The fitting/bladness is not a good sign and indicates he has a severe infestation. It is vital he gets the appropriate treatment without any further delay as without it he could die from this horrible condition. Please refrain from handling him as much as possible (and don;t even attempt to bathe him) as it can cause another fit.
If you read my posts on this thread it details how we approached treating the two mite girls, one of whom was very poorly indeed.
https://www.theguineapigforum.co.uk/threads/2-more-dying-piggies.122408/page-4
It's a lengthy thread but worth reading the updates as it contains a lot of helpful information on how to treat very distressed piggies who keep self-mutilating and ho we changed the treatment as they started to improve.
To quickly summarise the treatment they received:
a) we had to gas Beanie to be able to examine/treat her first time round
b) both girls had a course of doramectin+steroid injections ( 4 injections one week apart with the last two given without the steroid......then a further doramectin injection 3 months later) for the mites/itching (but Beanie actually had an extra doremctin + steroid injection 4 days after the first because she was so poorly)
c) they were on antibiotics (septrin) and OPIATE pain relief (tramadol maximum dose, change later to buprecare)
d) wounds were treated with flamazine cream or (in Beanie's case) sprayed with diluted warm F10 disinfectant (which is also antifungal).....and as you can see from the pictures, we had to dress Beanie's wounds and put her in a jacket to restrict the self-mutiliation
e) Once they were able to be handled without too much distress, both had imaverol bath/spray (Anti-fungal) and Beanie was also bathed in oatmeal gloop (water used to boil oats in) as a soothing skin treatment.
It is extremely distressing treating a severely infested piggie....but provided they have the correct treatment (ie the injections) , they can and do recover (as you can see from the most recent update on Dotty and Beanie's thread)
HTH
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