My mother has been suffering for several months with a sensation that she is being constantly bitten by something that we are never able to actually see. She has had the house fumigated and she spends her life cleaning the house, washing herself and everything else and applying all mannner of potions and lotions to no avail. There are certain things that make her worse, such as the sight of the cat, which is not allowed in the house anymore. She is becoming distraught, with no help from any doctors, any ideas anyone, please?