What can I add to my cat's diet for dandruff without extra calories?

You could try a shampoo like Duoxo Calm and see if that helps. You could also add an Omega 3 fatty acid like Free Form Snip Tips for cats and see if that helps keep his skin and coat healthy. Otherwise, he should be examined by a vet to determine the cause and treat.

Hmmm. Not sure the train of thought your vet was on. I commonly recommend fish oils, any fish oil supplement will work. There is no specific amount, though the biggest side effect is greasy stools. If you notice that, then you decrease the dose. It can take several months for you to see a change after starting fish oils. You can find a pet product at a pet store, or just use one from the human supplements section of a pharmacy or other store.

I suggest you use essential 6 supplement topically (it is spot-on) and an oral supplement like Wellactin. https://worldtails.securevetsource.com/itemView/view/198944_HomeDelivery.pml?productId=119092 https://worldtails.securevetsource.com/itemView/view/198944_HomeDelivery.pml?productId=101959 Cats do not take to bathing well. What you can do is use a leave on mousse that is for seborrhea (dandruff). You can use it twice a week until the dandruff decreases and then you can go to once a week. https://worldtails.securevetsource.com/itemView/view/198944_HomeDelivery.pml?productId=117952

You can find omega-3 fatty acids as a liquid sold in a bottle with a pump at some clinics and some pet stores. This may be easier for you to administer to your cat daily rather than having to squeeze the oil out of the capsule itself.

Due to her GI condition, I recommend to discuss any supplements or diet changes with her normal veterinarian to ensure these do not upset her condition. For pets in general, an omega 3 fatty acid supplement can help to improve coat health. There is also a diet line called Royal Canin that carries several different diet lines including diets specific for GI issues. In general this diet line contains supplements for coat health. If your veterinarian agrees, a diet change may also be beneficial. Please post any additional questions.

I would recommend the hills metabolic range in either wet, dry or mixed as long as total daily volume is within guidelines for target weight. The skin and coat should improve as he loses weight and regains mobility to groom himself, daily brushing will help in the meantime

Those spots on your kitty could be just dry skin causing itching bad enough to lose hair (do know that dry skin alone should not cause hair loss) but there are several things including fleas, allergies, skin mites, bacterial infection or endocrine disease which could also look the same way. There are a couple things you can do at home and they can help but they may not address the underlying cause. That's great that you are using an omega 3 fatty acid supplement this can help improve the skin health. Make sure it is a formula for pets (better absorption) and you may need to squirt it directly in his mouth. You may also try changing his diet to something like Royal Canin or Nutro as they are aimed at skin health. Also protect the area from trauma by having your kitty wear an elizabethan collar at all times. If the skin does not start improving within 2-3 weeks or if it is getting worse, have him examined by the veterinarian to look for other causes. Unfortunately, lotions and sprays don;t tend to moisturize as well as supplements and diet. There are some moisturizing sprays and your cat will need to wear an elizabethan collar at all times because otherwise he will lick the product. Moisturizing shampoos and conditions for pets are also an option but not all cats enjoy baths and may bite and scratch their owners. I hope this helps and please feel free to post any additional questions.