If she is on Ivermectin for skin issue that means she is being treated for a parisite ie mange
Does she have dandruff? if so a common basset skin issue is likely the cause called seborrhea. In most dogs seborrhea is a secondary condition caused by a more primary one however in basset it is most often a genetic primary cause of skin problems there is no cure but treating with with an anti seborrheact shampoo like selsun blue or a specialty product which can be as often as ever three days helps . Keep in mind the sampoo must remain on for at least 15 minutes to achieve full effectiveness. Also be sure to rinse tthourghly as well. that means twice as long as it takes so not soap suds are seen in the rince water,.
Other cause of the hot spot easily could be that 1. all the mite treated with the ivermected were not killed and the mange has returned.
2. fleas even if she is on a flea treatment flea bite allergies are the most common allergy in dogs and only a single flea bite is required to cause a hot spot.
the smell is likely a yeast infection this is general secondary to other skin problems so they need to be cleared up to deal with the yeast. As for bad breath provided the dog does not have peridontial disease nor has eaten something foal then lip fold pyderma enters the miix. check around the lower lips for a red area often swollon with pustuals sort of like really bad acne. Treatment is cleaning the area frequently often with acne type medication benzolyperoxide 10% shampoo. This regimine works for most dogs but if not surgery is possible to remove the lip fold that everything is getting traped in Mariah required such surger on both sides and it cleared up the problem and help with her breath emensely.
I find most vest are not very good at dealling with skin issues in dogs because of the primary secondary nature of most skin issues that is what you often see is not the real cause. ie yeast infection of the skin secondary to allergy etc. To sort through this I general suggest consulting with a vet that specializes in dermatology
find a dermatologist
Seborrhea In dogs
seborrhea
yeast infect Skin
Itch Relief
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