Hill's Prescription Diet y/d Thyroid Care Original Dry Cat Food

  • Price:

    $53.49 FREE 1-2 Day Shipping on this item

In stock
8.5-lb bag
  • 4-lb bag
  • 8.5-lb bag
- Quantity +


Hill's Prescription Diet y/d Thyroid Care is the safe, effective and easy way to manage thyroid health. Clinically proven nutrition to restore thyroid health in 3 weeks.

Key Benefits

  • Clinically proven to improve thyroid health in 3 weeks when fed as the sole source of nutrition
  • Decreases T4 hormone production while supporting kidney, heart and urinary health
  • Helps support a healthy body condition and a healthy immune system while also promoting a visible improvement in skin and coat
  • This recipe has limited iodine and controlled phosphorus and low sodium
  • Promotes desirable urine pH levels and is high in taurine, L-carnitine and omega 3 fatty acids

Special Note

Hill's Prescription Diets require a veterinary prescription. This product will not be shipped until a copy of a valid prescription authorization is faxed to 1-800-619-7973 or e-mailed to rx@chewy.com.

See all items by Hill's Prescription Diet

  • Item Number
  • Brand
    Hill's, Science Diet
  • Food Form
    Dry Food
  • Lifestage
  • Made in
    United States
  • Special Diet
    Prescription Food

Nutritional Info


  1. Corn Gluten Meal, Pork Fat, Whole Grain Corn, Soybean Mill Run, Dried Egg Product, L-Lysine, Chicken Liver Flavor, Potassium Citrate, Lactic Acid, Dicalcium Phosphate, Vitamins (L-Ascorbyl-2-Polyphosphate (Source of Vitamin C), Vitamin E Supplement, Niacin Supplement, Thiamine Mononitrate, Vitamin A Supplement, Calcium Pantothenate, Riboflavin Supplement, Biotin, Vitamin B12 Supplement, Pyridoxine Hydrochloride, Folic Acid, Vitamin D3 Supplement), Fish Oil, Choline Chloride, Calcium Carbonate, Calcium Sulfate, Dl-Methionine, Taurine, Vitamin E Supplement, L-Tryptophan, Natural Flavor, Minerals (Ferrous Sulfate, Zinc Oxide, Copper Sulfate, Manganous Sulfate), L-Carnitine, Mixed Tocopherols for Freshness, Phosphoric Acid, Beta-Carotene, Natural Flavors.

Caloric Content

  1. 517 kcal/cup
Guaranteed Analysis
Crude Protein 30.0% min
Crude Fat 20.0% min
Crude Fiber 3.5% max
Phosphorus 0.45% min
Phosphorus 0.85% max
Sodium 0.3% max
Iodine 0.2% max
Taurine 0.15% min
Carnitine 200 ppm min

Feeding Instructions

Because iodine intake from other food sources -- treats, another cats food, etc. -- can compromise the effectiveness of low-iodine nutrition, its critical that you follow your veterinarians feeding instructions carefully and feed only y/d.Adjust feeding amounts as necessary to maintain optimal weight. If you are unsure, ask your veterinarian. For best results & safety practices: Gradually transition to your pets new food over a 7 day period. Exclusively feed the recommended Prescription Diet dry and/or canned food. Keep fresh water available at all times. Have your veterinarian monitor your pets condition.

Transition Instructions

A gradual transition to a new pet food is important to avoid digestive upset. To transition, mix your pet’s current food with the new food. Over 7 days, gradually decrease the amount of the current pet food while increasing the amount of new pet food. In some cases, your veterinarian may recommend no transition or a shorter transition time.

Pet Lovers Also Bought

Customer Reviews

Hill's Prescription Diet y/d Thyroid Care Original Dry Cat Food is rated 4.7 out of 5 by 100.
Rated 5 out of 5 by from My cat gained over a pound! Love Chewy.com My nearly 16-year-old cat was losing weight and was down to 8.2 pounds, after being 12 or 13 throughout her life. Found out her thyroid was severely out of balance and vet recommended this food. She gained more than a pound in a month and is no longer racing around at night. And she loves it! Also, found this somewhat expensive food for $10 cheaper on Chewy.com and love that it is free shipping and we can have it shipped to our house on our schedule. Chewy's customer service is outstanding, received a kind note as soon as I ordered and her food arrived a day earlier than expected. Wish I would have found this site sooner!
Date published: 2017-02-07
Rated 5 out of 5 by from Working GREAT!!! My senior male cat was diagnosed with hyperthyroidism earlier this year and I was given the option of daily pills or switching his cat food. For convenience I chose the food against my vet's preference since he said he's never gotten good results using the food. Mind you, this is the stinkiest dry cat food I've ever fed (which made me worry that my finicky cat wouldn't eat it# but it must be palatable because he eats it just fine. His original thyroid level was around 14.5 and should be from 1 to 4 to be normal. Within three weeks, he was back to around 5.5 and my vet was utterly amazed and hopeful that this treatment may work for other patients at his clinic. After another 3 weeks, the level wad down to around 4, so we're thrilled. His next appointment is three months away, but based on all evidence to date, this food had done the trick. It's hard not to let him cheat and have a treat occasionaly #which would contain iodine), but he's a trooper.
Date published: 2013-10-18
Rated 5 out of 5 by from Hill's Perscription products are expensive but my cat's health is worth it! My cat was diagnosed with thyroid disease years ago. My vet prescribed Hill's y/d and her condition has been under control ever since. Agnes also loves the taste. I definitely recommend Hill's.
Date published: 2016-12-31
Rated 5 out of 5 by from It seems to work I was pretty skeptical that food alone could improve our cat's hyperthyroidism but it seems to work. It smells awful and is way too expensive but beats the alternative.
Date published: 2017-01-02
Rated 5 out of 5 by from It works my cat has hyperthyroidism. The blood test was REALLY really negative. We tried medicine but the med was affecting my cat's liver horribly. Stopped med and tried food. Cat thinks it okay...not loving it, but eating it. I am very happy, since the vet said thyroid irradiation would be next option to over $3K or so. He just needs to gain weight. I only ask Hills to work on better tasting food LOL.
Date published: 2017-03-02
Rated 5 out of 5 by from Rave reviews from my 2 cats! My 2 cats give this food rave reviews! My 10 year old cat with thyroid problems loves this dry food, easy for her to eat, too. My young 3 year old normal cat also loves to crunch these nuggets. Both dry and wet food have really helped my 10 year old to regain her normal weight quickly, plus receiving thyroid medicine. Love this product!! Great store, also!
Date published: 2017-02-16
Rated 5 out of 5 by from Great product, great service My senior cat was recently prescribed Hill's y/d for hyperthyroidism. I had concerns about introducing a new food, but I needn't have been. Both he and his brother (no health issues) love it. Great quality and delivered to my door in a day or two. Thanks Chewy!
Date published: 2017-03-02
Rated 5 out of 5 by from Very Pleased I'll never buy cat food any other way again! Great experience with Chewy and the food was deliver within just a few days.
Date published: 2016-12-30
  • y_2017, m_3, d_26, h_22
  • bvseo_bulk, prod_bvrr, vn_bulk_1.0.0
  • cp_1, bvpage1
  • co_hasreviews, tv_0, tr_100
  • loc_en_US, sid_69665, prod, sort_[SortEntry(order=RELEVANCE, direction=DESCENDING)]
  • clientName_mrchewy