Vomiting is a symptom, not a diagnosis. A cat may bring up food, fluid or a hairball for several reasons. Repeated episodes, changes in appetite or signs of illness should not be dismissed as an ordinary part of living with a cat.
Describe what you saw
Vomiting usually involves effort, with abdominal contractions or retching. Regurgitation can be more passive and may bring up undigested food. Coughing may also be mistaken for an attempt to produce a hairball.
A short video can help the veterinarian distinguish these events. Note when the episode occurred relative to meals, what came up and how your cat behaved afterward. A photograph is useful if it can be taken without delaying care.
Possible causes
Digestive irritation, parasites, swallowed material and underlying disease are among the possibilities. Kidney disease, thyroid disease and other conditions can also be associated with vomiting. The color of the material does not reliably identify the cause.
Tell your veterinarian about access to plants, string, toys, medicines or chemicals. An indoor cat can still swallow something dangerous. If poisoning or a foreign body is possible, seek advice promptly rather than waiting to see whether the cat vomits again.
Warning signs
Contact a veterinarian promptly for repeated vomiting, inability to keep water down, blood, marked tiredness, pain or a change in appetite. Collapse or breathing difficulty needs emergency care. Kittens, older cats and cats with existing disease may need help sooner.
Blood can be fresh red material or look darker. Do not attempt to judge how serious it is from appearance alone. An examination helps the clinic determine the next step.
What the examination may involve
The veterinarian will use the history and physical findings to decide whether blood tests, stool testing, imaging or other investigation is needed. Treatment depends on the cause and your cat's condition, rather than simply suppressing every episode.
Do not give a human anti-nausea medicine or leftover prescription. Do not routinely withhold food and water according to an internet timetable. Ask the clinic for specific feeding and hydration instructions suited to your cat.
Track improvement and recurrence
Keep a record of episodes, appetite, drinking, weight and litter-box changes. Follow the recheck plan even if signs improve temporarily. If vomiting returns, the record can help distinguish a recurring problem from an isolated event and guide the next investigation.