My friend lives in Russia and her cat has a strange condition. None of the veterinarians can help her. She has done so many blood work tests and spent so much money with no results and no explanation of why her cat does it. Every weekend she has a bad appetite and doesn't want to eat. If she eats she vomits. She makes weird movements like if she would chew on something and shakes her head. The cat is female, 2 yo, neutered. Some vet said its gastritis but its very weird that she gets sick only during the weekends. All tests show that she's healthy. She's normal during the week, she plays. They regularly give her medicine for worms. The food they give her is purina veteriary diets EN. Any advice will help. Maybe somebody heard of something like that?? Thanks