What can you do to help combat bad breath in your feline companion? Rule out serious illness and get any dental problems treated and under control. You will need to follow up with regular preventive dental care. A course of antibiotics may be required to get any bacterial infections treated and eliminated.
Breath mints for pets may provide temporary relief, but daily brushing or rubbing teeth with a gauze and an approved veterinary dentifrice is the best preventive measure available. Consult the Veterinary Oral Health Council (VOHC). The council evaluates dental care products for pets for efficacy by looking at clinical trials. The council also keeps a list of approved products for cats. See http://www.vohc.org/VOHCAcceptedProductsTable_Cats.pdf.
There is at least one water additive that is approved for cat dental health. Be sure if you choose to use this product that you also put a second bowl of plain water out for your cat.