"This is a great product! My senior cat is definitely been feeling better since we've been using this."







When cats stop eating—whether they’re old, sick, or just tiny—this high-calorie gel gives them the nourishment they need to bounce back.
Provides essential calories to promote weight gain
Stimulates appetite
Packed with 10 vitamins, 7 minerals
Boosts energy
“This product literally saved my kitties life. We had been to 4 vets and none of them could explain or cure her ongoing diarrhea. They did multiple tests, changed her food, put her on medications, but nothing worked. After using this product for 2 weeks she was a normal kitty. She is no longer a " splat cat" and she has been able to gain weight, eat normal food, and have a great life😊”
Melanie
Verified Buyer
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FREE Shipping Above $30
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Maximize Your Cat's Caloric Intake with This Recommended Duo!
The syringe is perfect for quick, measured calories, while the powder can be mixed into food for a sustained calorie boost throughout the day. Ensure your cat gets the total care they need to thrive!

Ready Cal High-Calorie Supplement For Cats
$21.99
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Ready Cal High Calorie Powder for Cats
$24.99
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Product Details
Ready Cal is an easy to use high calorie nutritional supplement that helps to provide the essential calories your cat needs daily to gain or maintain a healthy weight.
When our cats do not feel up to eating, it can cause low energy, depressed mood, and weight loss, which can quickly lead to malnutrition and further health issues.
This supplement helps to provide essential calories for cats that are not eating enough to maintain a healthy weight. Ideal for cats in their 'golden years' where maintaining weight is critical for slowing down the aging process.
Made in the USA with ten vitamins, seven minerals, and essential fatty acids, our vet formulated gel is designed for cats and kittens of all ages who may not be eating normally due to reasons such as stress, age, medical procedures, or illness.
Comes in a dial-a-dose tube for accurate dosing, with a natural fish taste cats love. Manufactured without artificial flavors or dyes.
Ingredients
Malt syrup, soybean oil, corn syrup, cane molasses, salmon oil, dl-alpha tocopherol acetate (vitamin E), sodium benzoate (preservative), manganese sulfate, magnesium sulfate, calcium pantothenate, niacinamide, iron proteinate, pyridoxine hydrochloride, vitamin A acetate, thiamine hydrochloride, mixed tocopherols, sodium chloride, trisodium phosphate, riboflavin, potassium iodide, choline bitartrate, d-activated animal sterol (vitamin D3 supplement), folic acid, vitamin B12 supplement
Directions
To acquaint your cat with the flavor, place a small amount of gel on its nose or in the mouth.
To supplement your cat's caloric or nutritional intake: 5 cc (or 1 teaspoon) per 10 pounds of body weight daily.
When your cat is not eating its full ration: 10cc (or 2 teaspoons) per 10 pounds of body weight daily.
Shipping & Returns
Standard Shipping (arrives in 5-8 business days)
All orders above $30 are eligible for free shipping! Please note that we only ship to addresses in the lower 48 of United States. We do not ship internationally or to AK/HI at this time.
Expedited Shipping (arrives in 2-3 business days)
Flat rate of $19.99 USD. Orders placed before 3pm EST Monday - Friday (non holidays) ship the same day. In-stock items are normally shipped within 1-2 business days. Expedited and overnight shipping options are not available to Hawaii, Alaska and PO Boxes. We do not ship on holidays.
Hastle-free Returns
We are happy to accept returns of unopened, unexpired products purchased directly from our website within 30 days of purchase. Please note, we DO NOT accept returns of opened or expired products. We also do not accept returns of items purchased from Amazon or other retailers.
Please send your returns using the carrier of your choice to:
Under the Weather Pet (ATTN: Returns)
1360 Marshall Avenue Williston, VT 05495
Please ensure to include your name and order number.
Once your return has been processed, it may take 3 - 10 days for the refund to be posted to your account.
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Veterinarian Formulated
Every product we manufacture has been developed in close collaboration with verterinarians - that means they’re safe, and they work!
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Manufactured in the USA
All of our products are manufactured right here in Vermont, USA, always using the highest quality ingredients.
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Fast Shipping
Your hands are already full taking care of your furry friend. Save the trips to the store with our fast shipping!
Overall rating: 4.3076925 / 5 from 195 reviews.
AI Generated Review Summary
Ready Cal® High-Calorie Supplement for Cats is a product designed to help cats maintain optimal weight and energy levels, especially as they age. It is praised for its effectiveness in improving feline health and overall well-being. Customers have mixed opinions on its taste, syringe, and the amount, but it is generally considered helpful for fussy eaters and weight management.
Summary topics
- Eating Behavior: 6%
- Weight Management: 14%
- Cat Health Improvement: 32%
- Taste Acceptance: 12%
- Supplement Effectiveness: 12%
Review topics: [].
Review highlights
- "My 17 year old cat really loved Ready Cal High-Calorie Supplement!" —
- "I still feed this to her occasionally, but she is now fully eating cat food without issues." —
- "She likes the flavor, no issue licking it straight off my finger." —
Reviews
Texture
"The texture is messing with them. They want to eat it, but don’t want a big glob of it in their mouth. I mix it with another paste that they love eating but don’t provide what this paste does. I either do that or put it on the inside of a front leg so they’ll have no choice but to eat it."
Vitamin packed
"Been giving this to my baby for years now, off and on. Just to give her some extra suppliments and weight gain. She loves it."
Donated to feline rescue
"I donated it to my local feline rescue. It's their preferred milk substitute for all their kittens."
My cats very picky
"The product itself when I can get my cat to consume it is working well, he has at least maintained his weight and not lost anymore, he seems to smell a fishy smell and he HATES ANYTHING SEAFOOD so I would love if you had a chicken or turkey flavored weight gain, I only put it in one meal right now because he turns his nose up, I heat his fish under water add product then heat a spoon make a wet pile? And add his wet food and mix it in this is the best way after trial & error, I definitely will be getting another one , it's just he needs to eat so if he turns his nose up at his food I can't do it at every meal, but it's working and definitely worth it! If your cat eats fishy things they will love it!"
Really helps,thanks
"Really helps,thanks"
You send surveys too soon.
"Give customers a chance to use the product and see results before sending surveys. Too soon to know!"
21 year old cat
"My 21 year old cat loves this stuff! She is rather finicky with her food in her golden years. This gel gives her the extra vitamins and calories she needs to keep her feeling better."
"Cat would not eat it."
"My kittens don't like it. They are not eating it even if I mix it with other food. 😔"
Q&A
- I have a diabetic cat and see this contains molasses and corn syrup. Could this be used to treat hypoglycemia and what is the sugar/glucose amount per cc?
- Absolutely. Each Teaspoon (5 grams) provides about 3,200 mg of readability available sugar in the form of Corn Syrup, Malt Syrup and Molasses. This will help boost the sugar levels in the blood. In addition it also provides B vitamins which helps as a co-factor in energy metabolism. Please be sure to see your vet before starting any supplement as every cat's health is different.
- My cat is 17 years old and drinks but will not eat. I've tried to get her to eat the feed from your tube but administering it is problematic. I placed some on he paw as directed but she didn't even lick it. Is there any product you carry such as pills or eye drop administered product for infection or appetite enhancement? She will drink some of the water from canned tuna, Perhaps I could more easily feed her with an eye dropper. Do you carry them?
- We do not carry a product that is administered by an eyedropper at this time. You could try mixing the gel with warm water and then giving it in a dropper.
- Could this product make my kitten slobber
- It is definitely a tasty product but we haven’t heard this one before! If the slobbering is frequent we suggest calling your vet just to make sure things are normal.
- Is this suitable for a kitty with CKD?
- This is great for cats with many different health issues, including CKD, however every cats health is different so we suggest you speak with your vet before starting!
- My cat has a thyroid problem, takes med, now needs meds to protect his liver and spleen. Lost a lot of weight will this have a effect on his other meds? He is 16 and weighs 6 1/2 pounds.
- While many cats benefit from Ready Cal, including those with thyroid issues, however every cats health is different so we suggest you speak with your vet about how it will interact with your cats medication.










