Treating your cat's flatulence can be simple or more complicated, depending on the cause.
Diet Management
Perhaps the most obvious treatment plan (if food alone is to blame) is changing up your cat's diet. One possible change is lowering the amount of fiber or soy. This can be helped by switching brands of food. If you switch, do not change out all the food at once. The process should occur gradually over the course of a few weeks in order for your cat's digestive system to properly adjust. As such, mix some of the new food with the old, and continue increasing that substitution until your cat is fully ingesting the new brand.
It is helpful to also deter your cat from overeating or consuming their meal too quickly. You can help in this by giving them smaller meals, yet give them more frequently. Making use of an automatic food dispenser, if possible, can assist in this matter. Also, when you have more than one cat, consider feeding them alone as to not bring about any competition which can make them eat faster and overeat.
If a food allergy has been discovered, then it is best to try to eliminate the culprit from the diet completely. A hypoallergenic food diet can serve you best in this case.
Medical Treatment
Specific treatment is necessary in the event that a larger medical issue has been discovered, such as disease or an infection of some sort. In the case of IBD, the condition can be helped by managing the diet. If not, then your vet may place your cat on a course of corticosteroids, which have immunosuppressive and anti-inflammatory properties. Antibiotics may also be useful in treating IBD if other treatment plans have failed.
Antibiotics, are also prescribed in the treatment of an infection. If your vet has placed your cat on antibiotics, be certain to follow the exact care plan in order to properly treat the infection. If these medications are not given correctly, your cat may develop drug-resistant bacteria, and their initial infection may not go away. There are risks when taking antibiotics such as fever, diarrhea, and other side effects. However, your vet should conduct the necessary tests to determine the exact antibiotic that can best treat the infection while offering minimal side effects.
If parasites are found, then your vet will begin treatment immediately. The exact medication is determined once a positive fecal exam has been performed. Just as the case with antibiotics, it is important to give the medicine to your cat per your vet's instructions as your cat become re-infected with the same parasite.