Petromalt The original hairball remedy for cats Cats and Hairballs When cats clean themselves, their tongues often pull loose hair from the coat. When swallowed, it can accumulate in the gastrointestinal tract. This nearly indigestible material becomes a "hairball" which can interfere with normal digestion and elimination. Symptoms of hairballs include constipation, straining during a bowel movement, dry cough and vomiting after meals. The use of Petromalt and regular brushing of the cat's coat will generally eliminate these problems.