Cat retching but not vomiting and eating normally may be caused by hairball syndrome. In the early stage, retching and vomiting may occur. In severe cases, cats may suffer from loss of appetite, poor energy, constipation, and even intestinal obstruction. This requires Treat your cat promptly to avoid worsening of the condition. You can give cats cat grass or hair removal cream to help cats expel hair balls. It is best to feed them once a week, 3 to 5 centimeters each time.