What should a female cat do if she suddenly vomits while nursing?

Cats vomiting during lactation should be distinguished from physiological or case-specific. Physiological vomiting is often caused by excessive hunger, or over-eating, or strenuous exercise. Pathological vomiting is often characterised by repeated vomiting, which may be accompanied by digestive juices and blood/clots, and in some cases by hairball syndrome caused by licking too much hair. Do not give medication during the nursing period as it may aggravate the condition and affect the unweaned kittens.