The two most common places to get reinfested by scabies is your hands and feet, they love to dwell in these places because it is a perfect place to hide in your skin folds to protect them and they are usually contracted through hand contact or contact with carpeting.

Try using something called Johnsons Foot Soap, it is a powder taht you put in a foot bath which contains Borax, Iodide and Bran. It is very cheap you get like 8 pouches for about 5$. It soothes your feet while softenining corns and calluses or hard feet, it also relieves itching associated with scabies. It is a real good foot bath powder if your feet are hard and thick and maybe the scabies treatments are not penetrating your skin because of this.

Take foot baths using baking soda for a few weeks or until you notice your skin on your feet is back to normal, it is hard to kill scabies on the foot area because the skin is already to thick because you have been using them to walk for years and scabies create a skin layer around them to protect them. I would suggest starting with baking soda foot baths as it will soften up the skin and allow the treatment to be more successful.