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

By Hill's Prescription Diet
Rated 4.6297 out of 5 stars
Veterinary Diet Item
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Hill's Prescription Diet y/d Thyroid Care Original Flavor Dry Cat Food, 8.5-lb bag slide 1 of 11
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Hill's Prescription Diet y/d Thyroid Care Original Flavor Dry Cat Food, 8.5-lb bag slide 1 of 11

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This Item - Hill's Prescription Diet y/d Thyroid Care Original Flavor Dry Cat Food, 8.5-lb bag
Rated 4.6297 out of 5 stars
$71.99Chewy Price

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About This Item

  • 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.
  • Formulated with S+OXSHIELD to meet specific nutrient standards, shown to promote a urinary environment that helps reduce the risk for struvite and calcium oxalate crystals.
  • Offers same great taste and benefits as they did prior to the introduction of the S+OXSHIELD seal.
Play Video: Learn More About Hill's Prescription Diet From Our Team of Experts
Learn More About Hill's Prescription Diet From Our Team of Experts

Hill's Prescription Diet y/d Thyroid Care for Cats

Groundbreaking Nutrition for Thyroid Health

Hill's breakthrough formula was designed to help felines with hyperthyroidism thrive. Cats with this disorder have an overactive thyroid gland—meaning it produces too much of the thyroid hormone—but limiting iodine in your cat's food can help regulate it. Prescription Diet y/d does that and more, all in a tasty kibble your cat will love. You may even see a difference in as little as three weeks.

Clinical Nutrition

With Hill's, it's not just high-quality ingredients that count. Their focus is on the proper balance of nutrients in every recipe. So, Hill's designed food to help pets with health conditions, providing the right nutrients to support their health. Hill's alliance with veterinarians puts them in a position to find a nutrition recommendation for your pet, no matter what health issue your pet is facing.

Formulated by Veterinarians

Hill's Prescription Diet started with a veterinarian's belief that some health issues could be managed through nutrition. What began as a theory has now been proven through extensive research by a team of over 220 vets, PhD nutritionists and food scientists. The results can be seen in Hill's Prescription Diet therapeutic pet foods.

Meeting the Highest Standards

Providing a food that delivers exactly what it says it does is Hill's number one priority. In fact, they perform over five million safety and quality checks every year. They've established relationships with trusted suppliers and will only accept ingredients that meet stringent standards.

The Taste Factor

You might know that Hill's Prescription Diet is good for your pet, but she's only concerned with the taste. Even though they place a heavy emphasis on nutrition, Hill's hasn't forgotten about palatability. Savory ingredients are combined to produce foods with enticing aromas, textures, and shapes that your pet can't resist.

How Hill's y/d Helps Manage Thyroid Health

Key Nutrients

  • Limited Iodine
  • High in omega-3 fatty acids
  • Controlled phosphorus and low sodium

Health Benefits

  • Decreased T4 production
  • Supports kidney, heart and urinary health
  • Promotes skin and coat health

About Hill's Prescription Diet

Hill's mission is to help enrich and lengthen the special relationships between people and their pet. Their Prescription Diet product line delivers clinically proven nutrition that supports common pet health concerns, from digestive and urinary health to aging and weight management.
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Questions & Answers

17 Customer Questions

I have 2 cats and only has a hyperthyroid. The vet meds have made him so sick that I wanted to try an alternative. Will this food be harmful if eaten by my cat who doesn't have hyperthyroidism but has asthma? They share a dry food bowl and feeding them independently would be a challenge. Thank you.
Answer by ChewyNov 15, 2018
Since this is a prescription food formulated to meet specific diet restrictions from known health issues, this food should not be fed to any other animal than the one prescribed due to the restriction of specific nutrients. Prescription diets can be detrimental to an otherwise healthy pet if that pet doesn't have the ailment for which the food is designed.

Is this food for an over-active or under-active thyroid problem (i.e. hyper- or hypo-thyroidism)?
Answer by ChewyApr 23, 2018
This formula is not designed for over-active or under-active thyroids specifically, instead it helps to promote the overall health of the thyroid. It contains limited iodine to decrease T4 hormone production. This product also supports kidney, heart and urinary health with controlled phosphorus, low sodium, and a desirable urine pH.

Is it safe to feed this to a hyperthyroid cat does take methimazole, but not always the full dose? She is also in very early renal failure. Are the phosphorus & sodium levels low enough to be beneficial?
Answer by ChewyNov 20, 2019
Due to your feline's underlying medical condition, we suggest speaking to your veterinarian to determine if this is the best option for your cat.

Does the 8.5 lb bag not have the S+OXSHIELD? when I hover over the 8.5 lb option, the S+OX logo disappears from the photo of the bag.
Answer by ChewySep 11, 2018
Both the 4 and 8 1/2 pound bags are formulated with the S+OXSHIELD to meet specific nutrient standards, shown to promote a urinary environment that helps reduce the risk for struvite and calcium oxalate crystals.

ReviewsWrite a Review

Rated 4.6297 out of 5 stars
316 Reviews
Would recommend to a friend

316 Customer Reviews

Rated 5 out of 5 stars
By CatCaretaker on Sep 16, 2022

He eats it

Our elderly cat dines on this twice a day in lieu of pills (we all know how giving a cat a pill goes). What he doesn't eat at a meal, he nibbles at throughout the day and is a midnight snacker. It stays fresh in the bag and will last a day or two in the bowl if you have a finicky eater. Chewy is the best for ordering it!

Rated 5 out of 5 stars
By WalkerB on Jul 21, 2022

Hyper thyroid

We discovered our underweight cat who never stops eating has a hyper thyroid which now requires special food. We have this in a canister where the food drops down so he can eat as much and whenever he wishes. He hasn't gained weight yet, but he likes it so we are hopeful.

Rated 5 out of 5 stars
By Jasper on Jul 29, 2022

y/d Thyroid Care

My vet is having a hard time getting this in so they suggested I purchase the dry and wet y/d food from Chewy. They were delivered on time and in good shape. This is the only food my cat eats because of his thyroid condition. Thanks Chewy!

Rated 5 out of 5 stars
By Tabb on May 23, 2022

This food really works!

I'm convinced that this food bought our adult cat over three more wonderful, healthy years with us. She was diagnosed with hyper thyroid around 11 years, after we took her to the vet because she was throwing up her normal Royal Canin (not cheap food either), and had diarhea. We fed her nothing but the Hill's Thyroid Care ever since and did her nightly medicine cream in one ear. After putting her on this food (and the prescribed medicine) her symptoms cleared up almost right away. Her coat got healthier and shinier and she just seemed to be happier in general, more active. She rarely threw up her food anymore and usually it was just because she ate it too fast. She was a pretty picky eater and I was worried she wouldn't like this food, but she never got tired of it. Yes in the beginning the food seemed like an expensive option, but if you love your kitty, its more than worth it, plus it seemed to regulate her diet and she wasn't begging for food as much as with the old stuff.

Rated 5 out of 5 stars
By Jet1 on Jul 16, 2022

Efficient Rx Processing

The timeframe from order to Rx Verification and receipt of Rx food was Great. This is a drastic change from my previous experience. Thank you

Rated 5 out of 5 stars
By Cocoasmom on Jun 29, 2022

Cocoa loved it!

Have had problems in past of cats not liking rx diet but Cocoa was after this as soon as I opened - thinks it's treats.

Rated 5 out of 5 stars
By Smooch on Mar 30, 2022

Saved my cat’s life

First off, Chewy is an amazing company that helped me save my cat, as allowed returned food that wasn’t working for us to be donated. Best pet supply company ever. With sincere and eternal thanks! My 17 year old cat Smoochy was diagnosed with severe thyroid disease and was losing weight rapidly. My husband called her our little bowling ball at 8 lbs., but she went down to 4 1/2 pounds rapidly and was literally skin and bones. We had tried methimazole pills which were impossible to administer her and also the transdermal / rubbed in her ear version which made her throw up. It was too hard chasing her around to administer any kind of medicine, I didn’t want my 17-year-old cat to die being afraid of me. I didn’t think this food would work but it was my last resort. She did not like the canned food, but eats the dry food daily. I put a little water in it and let it soften as her teeth are bad, but this is the ONLY food I feed her and it literally saved her life. She went from 4 1/2 pounds to 7 pounds in just a couple of months. I know it seems expensive per bag, but it lasts for a very long time in the long run it cost about the same as all of the food and treats I was feeding her that she was devouring before trying YD. I highly highly recommend, it saved my cat’s life.

Rated 5 out of 5 stars
By Fussyoldcatlover on Apr 3, 2022

My two old fussy cats love it,,,!

I was afraid they wouldn't eat it but they love it and now they won't even eat the regular food. They both have gotten hyperthyroid as they've gotten older so it's great because now they can both eat it. And chewy delivered it in 2 days,! And they'll take back what they won't eat. Can't ask for more than that!

Rated 5 out of 5 stars
By Aliko on May 11, 2022
Top 250 Contributor

Keeps her fit

My baby is doing well on this just add some laxatone every few days because its all carbs kind of makes her constipated but it keeps her from taking the meds and she's turning 16 soon

Rated 5 out of 5 stars
By Mary on Mar 19, 2022

Picky Eater

My cat is 13 and is a VERY picky eater. She loves this food. As soon as I poured the food in her bowl she began devouring. It’s the only thing she eats. She will not touch the moist food paired with this. No surprise. She has never eaten /liked moist food.