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

Hill's Prescription Diet y/d Thyroid Care with Cat Food
Dry » 1.5kg Bag
Dry » 5kg Bag
Wet » 24 x 156g Cans

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  • Dry » 1.5kg Bag £17.50
  • Dry » 5kg Bag £44.99
  • Wet » 24 x 156g Cans £41.50

Selection of 3 products from

£17.50 to £44.99


Hills Y/D available from VIoVet

Hill's y/d is the first and only clinically proven nutrition that is specially formulated to help support your cat's thyroid health. The y/d diet carefully restricts the levels of iodine to help support thyroid function, particularly in cats with hyperthyroidism, whilst providing a complete daily nutrition with a taste your cat will love.

Additional benefits for overall health

Hills y/d diet also provides extra benefits in addition thyroid health, including:

-Supports kidney health with controlled phosphorus and low sodium
-Helps maintain bladder health with controlled mineral levels
-Promotes heart health with essential nutrients like taurine and carnitine
-Promotes healthy skin and a luxurious hair coat with high levels of omega-3 and -6 fatty acids.

Because iodine intake from other food sources -- treats, another pet's food, etc. -- can compromise the effectiveness of low-iodine nutrition, it's critical that you follow your veterinarian's feeding instructions carefully and feed only Hills Y/D.

Hills y/d Feeding Guide

Daily Feeding Guide:

Important Feeding Information

  • These amounts are a starting point only. Your cat may need less or more food to maintain proper weight. Adjust as needed. If you are unsure, ask your veterinarian.
  • With your veterinarian's approval, mix increasing amounts of your cat's new food with decreasing amounts of the old food over a 7-day period.
  • Prescription Diet® formulas are available in a wide variety of dry foods and treats for your cat's unique needs, and canned foods with delicious flavors your cat will love. Supplementation with other foods or treats is unnecessary and may decrease the effectiveness of the food. When using with canned food, decrease the amount of dry food to avoid overfeeding.
  • Keep fresh water available at all times!
  • For best results, have your veterinarian monitor your cat's condition.
  • To prevent suffocation, keep this plastic bag out of the reach of pets and children.

Adult maintenance

Weight of Cat Amount of Hills Y/D per Day
6 lb (2,7 kg) 1/4 cup (30 g) - 3/8 cup (45 g)
10 lb (4,5 kg) 3/8 cup (45 g) - 5/8 cup (80 g)
14 lb (6,4 kg) 1/2 cup (65 g) - 3/4 cup (95 g)
18 lb (8,2 kg) 2/3 cup (85 g) - 7/8 cup (110 g)



Liver, pork, chicken, maize, rice, animal fat, vitamins, digest, cellulose, minerals, trace-elements, fish oil, L-carnitine.


Maize gluten meal, maize, animal fat, dried whole egg, flaxseed, L-lysine, digest, minerals, fish oil, dl_methionine, L-carnitine, rice, taurine, vitamins and trace-elements.



Average Nutritional Contents

As Fed Dry Matter kcal/100g
Beta-carotene 0.6 mg/kg 2.1 mg/kg 0.05 mg
Calcium 0.25 % 0.86 % 192 mg
Carbohydrate (NFE) 9.1 % 31.4 % 7 g
Fat 7.5 % 25.9 % 5.8 g
Fibre (crude) 0.9 % 3.1 % 0.7 g
Iodine 0.04 mg/kg 0.14 mg/kg 3 ug
L-Carnitine 188 mg/kg 648 mg/kg 14 mg
Magnesium 0.02 % 0.07 % 15 mg
Moisture 71 % 54.5 g
Omega-3 fatty acids 0.19 % 4.61 % 150 mg
Omega-6 fatty acids 1.34 % 0.66 % 1030 mg
Phosphorus 0.17 % 0.59 % 131 mg
Potassium 0.25 % 0.86 % 192 mg
Protein 9.9 % 34.1 % 7.6 g
Sodium 0.07 % 0.24 % 54 mg
Taurine 722 mg/kg 2490 mg/kg 55 mg
Vitamin A10] 18756 IU/kg 64675 IU/kg 1440 IU
Vitamin C[sup:10] 12 mg/kg 41 mg/kg 0.9 mg
Vitamin D[sup:10] 237 IU/kg 818 IU/kg 18 IU
Vitamin E[sup:10] 215 mg/kg 741 mg/kg 17 mg

Metabolisable Energy

As Fed Dry Matter
kcal/100 g 130.3 449.1
kJ/100 g 545 1879


Average Nutritional Contents

As Fed Dry Matter kcal/100g
Beta-carotene 1.5 mg/kg 1.6 mg/kg 0.04 mg
Calcium 0.8 % 0.85 % 189.13 mg
Carbohydrate (NFE) 32 % 34.04 % 7.57 g
Fat 23.4 % 24.89 % 5.53 g
Fibre (crude) 1 % 1.06 % 236.41 mg
Iodine 0.18 mg/kg 0.19 mg/kg 4 ug
L-Carnitine 500 mg/kg 531.91 mg/kg 11.82 mg
Magnesium 0.07 % 0.07 % 16.55 mg
Moisture 6 % 1.42 g
Omega-3 fatty acids 1.01 % 1.07 % 238.77 mg
Omega-6 fatty acids 3.63 % 3.86 % 858.16 mg
Phosphorus 0.57 % 0.61 % 134.75 mg
Potassium 0.85 % 0.9 % 200.95 mg
Protein 32 % 34.04 % 7.57 g
Sodium 0.24 % 0.26 % 56.74 mg
Taurine 1974 mg/kg 2100 mg/kg 46.67 mg
Vitamin A10] 13623 IU/kg 14492.5 IU/kg 322.06 IU
Vitamin C[sup:10] 110 mg/kg 117.02 mg/kg 2.6 mg
Vitamin D[sup:10] 1316 IU/kg 1400 IU/kg 31.11 IU
Vitamin E[sup:10] 610 mg/kg 648.94 mg/kg 14.42 mg

Metabolisable Energy

As Fed Dry Matter
kcal/100 g 423.1 450.1
kJ/100 g 1770 1883

Signs of feline hyperthyroidism

Signs of Feline HyperthyroidismTransitioning from Anti-Thyroid Medication to Hills Y/D Feline

Need help or advice? Contact us:

  • Landline: 01582 842096
  • Mon - Fri: 8:30am - 5:00pm
  • Sat: 9:00am - 1:00pm (Collections only)
  • Email: [email protected]

All prices include VAT where applicable.

Delivery Information

How quickly do you deliver?

Under almost all products on our website is an Estimated dispatch time, check this for a delivery prediction specific to the item you are looking to purchase. These badges are updated live based on the stock levels we have and also those of our suppliers - so are usually very accurate, but cannot be guaranteed. In more general terms, we aim to dispatch all orders within 1 working day of receiving payment (and a prescription if required). If we cannot do so within 3 working days we will contact you by email.

What do you charge for delivery?

For UK delivery, we charge the following:

Order Total Weight Delivery
£0-£28.99 Under 2kg £2.99
2kg+ £4.99
£29-£38.99 Under 2kg Free
2kg+ £4.99
£39+ Under 2kg Free
2kg+ Free

Prices quoted are for delivery to all parts of mainland UK except certain Scottish postcodes (where the price is higher for items sent by courier. Delivery of food abroad (including Channel Islands, N. Ireland and other islands around the UK) is charged at a higher price and free delivery is not available. Temperature controlled products are also not always subject to the standard and/or free delivery options.

For full information on our delivery charges, including prices on heavy deliveries to Scotland and abroad, see our delivery information page.

We can deliver most items to all around the world, but prices do vary. To find the exact cost of shipping your item, and to see all options available, follow these steps:

  1. Put the items you wish to order in your basket
  2. Proceed to checkout and enter your delivery address, including country
  3. Delivery information including price will automatically update to what is available to you

Delivery of aerosols

Due to restrictions aerosols can't be sent by Royal Mail. We appreciate your understanding.

Delivery of temperature controlled items

Some products, such as non-ambient items and frozen food, need to be delivered in insulated packaging to prevent them from getting too warm (or too cold) during transit from us to you. Purchasing any of these items in your order will result in a £1.99 charge being added to the total to cover the high cost of the insulated packaging materials. You only pay the £1.99 once per order, regardless of how many temperature controlled items you purchase in that order.

How do I cancel or return an order?

Please call us as soon as possible if you need to amend or cancel an order on 01582 842096. If your order has been processed for dispatch we will be unable to cancel or amend the order. You will however be able to return your product for a full refund*.

To return an item, you must contact us by phone or email to arrange this BEFORE posting any product back to us. We will explain the process at this stage for you.

*For full details on returns, see our terms and conditions page.

Reviews (22)

Q & A

Below are some recent questions we've received regarding Hill's Prescription Diet y/d Thyroid Care with Cat Food, including answers from our team.

2 May 2016 at 10:11am

Y/d wet or dry?


  • VioVet customer since 2016
  • From: CHANNEL ISLANDS, United Kingdom

My cat normally eats dry food and has been recommended the y/d diet by our vet. Can she continue just eating the dry food or does it have to be mixed with the wet food?

  • Non-Executive Director

You can choose wet or dry, or a combination of the two, it will be fine as far as her hyperthyroid treatment is concerned. The main issue with this diet is that it tastaes a bit boring to cats, so they tend to go off it after a while. Using both wet and dry can help to provide interest, so I would recommend that is what you do. It is important that she does not eat any other type of food at all.

16 September 2014 at 9:22am

Hills y/d variety


My cat has a thoroid problem & won't rejects Felimazole tablets in any form.
Q1. Does the y/d only come in one variety (which my cat doesn't like) - are there any other varieties.
Q2. Is there any way of making it taste like Chicken or Beef?

  • Non-Executive Director

There is only one form of y/d diet and it is true that lots of cats do not enjoy it. Adding anything significant to it to improve the flavour will probably prevent it from being fully effective, so I would not recommend that. If hunger will encourage your cat to eat it then you will have to work on that, but this is a problem for many cat owners.

31 August 2013 at 4:37pm

Is y/d ok for multicat households?

kay barnett

i can't find anywhere, whether it is OK for prescription y/d to be fed to other healthy cats within the household, or must it ONLY be fed to the cat diagnosed with hyperthyroidism?

  • Non-Executive Director

This diet is safe for other cats to eat, but ideally they should get some other foods as well. A hyperthyroid cat should not be allowed to eat anything else at all. The y/d diet is not especially tasty, so your other cats would probably prefer other food anyway. You have to make sure you do not offer any other foods when the hyperthyroid cat is present, or that one will not want to eat the prescription food either. If you can cope with the hassle of organising the feeding, the y/d dose seem to be very effective.