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VetClassics   CAS Options (Extra Strength Immune & Antioxidant Support) - 120 Chewable Tablets

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12 Reviews

"CAS Options by VetClassics is a wonderful product recommended by my vet for our ..."  Read all reviews

Item Number: RES1014
Price per Unit*: $0.54 per Tablet
* Price Per Unit may reflect product's price per capsule, tablet, ounce, fluid ounce, etc.
12 In Stock. This item will ship today if ordered within 14 hr 58 min
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A powerful blend of four functional mushrooms: Maitake‚ Reishi‚ Shiitake‚ and Turkey Tail combined with antioxidants to provide extra strength immune support. Formulated to support and balance the immune system to promote overall health and well-being for pets‚ especially during times of stress.

These statements have not been evaluated by the Food and Drug Administration (FDA). These products are not meant to diagnose‚ treat or cure any disease or medical condition. Please consult your doctor before starting any exercise or nutritional supplement program or before using these or any product during pregnancy or if you have a serious medical condition.

  • MFG # CCAS-120V
  • UPC # 731933190628
Official Website:

Active Ingredients Per 3 Grams Tablet:
Reishi Mushroom 578mg
Shiitake Mushroom 446mg
Turkey Tail Mushroom 150mg
Maitake Mushroom 95mg
N-Acetyl-L-Cysteine 79mg
Vitamin C (Calcium Ascorbate) 60mg
Coenzyme Q10 1mg
Selenium 26mcg
Vitamin A 1050 IU
Vitamin E (D-Alpha Tocopheryl Acetate) 53 IU

Inactive Ingredients: Dicalcium Phosphate‚ Distilled Monoglycerides‚ Magnesium Stearate‚ Microcrystalline Cellulose‚ Natural Flavoring‚ Silicon Dioxide.

Made in the USA.

For use in dogs and cats over the age of 12 weeks.

Usage for Cats:
Cats up to 5 lbs. – ½ Tablet Daily
Cats over 5 lbs. – 1 Tablet Daily

Usage for Dogs:
Dogs up to 25 lbs. – ½ Tablet Twice Daily
26 to 50 lbs. – 1 Tablet Twice Daily
51 to 100 lbs. – 2 Tablets Twice Daily
Dogs over 100 lbs. – 3 Tablets Twice Daily

Use only as directed by your veterinarian.

For animal use only.

Keep out of reach of children and animals.

In case of accidental overdose‚ contact a health professional immediately.

Safe use in pregnant animals or animals intended for breeding has not been proven.

If animal's condition worsens or does not improve‚ stop product administration and consult your veterinarian.

Notice: Responses to supplements may vary by animal.

  • Made in the USA

Ratings and Reviews

Write a Review
  • 4.5
5 12
  • 12 Reviews
    • Verified Buyer

      Good for my large dogs

      from BRIDGEPORT WV on 8/28/2020
      Using for growth on paw and immune builder. similar to what i take for medicinal mushroom blend. cost is okay when compared to vet bills and bad chemicals or antibiotics. We are getting results.


      Right sized for dosing my dogs sizes and good potency when trying to avoid surgery.


      review-checkI would recommend this item to a friend.

      from California on 9/09/2019
      These tablets are huge!! Impossible grind an entire tablet and hide it in my cat’s canned food over the course of a day. Additionally, it has an odor so my cat refused his food. Wasted a lot of money!




      Tablet size & dosing amount
    • CAS Options extra strength

      from New York on 12/27/2018
      My dog was just diagnosed with cancer and my vet recommended this CAS Options (Extra Strength Immune & Antioxidant Support) by VetClassics highly.


      My dog likes the flavor of the tablets. So there is no problem getting him to take them.


      review-checkI would recommend this item to a friend.
    • Verified Buyer

      Keeps my old hound healthy

      from Oregon on 12/21/2018
      This CAS Options (Extra Strength Immune & Antioxidant Support) by VetClassics was recommended to me by a veterinarian after my dog underwent surgery to remove a cancer. Our large black lab mix is now 13 and a half and still with us, looking pretty hale and hearty. He doesn't love the taste of these, but if we put them in his food bowl he'll eventually eat them. I wish PureFormula carried the CAS Options Soft Chews.


      Does its job


      Really expensive, especially if you have a big dog!
      review-checkI would recommend this item to a friend.
    • Verified Buyer

      Awesome Immune Support

      from Radford VA on 11/23/2018
      CAS Options by VetClassics is a wonderful product recommended by my vet for our dog with cancer.


      CAS has been a godsend for our dog. He gobbles up the tablets.


      review-checkI would recommend this item to a friend.
    • So far so good

      from Massachusetts on 10/31/2018
      Started this with our 12 yo pup who has had some strange episodes that blood work, urine/stool samples, and physicals couldn’t diagnose. I changed her food and started the CAS options at the same time. She has had no more episodes and seems to be more alert and comfortable! I don’t know which one is or if both are responsible but I’m grateful! I’ve started our other dog on these too.


      Both our dogs love the chewables and one of our dogs can be picky.


      Costly to use for 2 big dogs.
      review-checkI would recommend this item to a friend.
    • Verified Buyer


      from Newark, DE on 3/26/2017
      I just received my bottle of CAS Options, Extra Strength Immune & Antioxidant Support for Dogs by Resources but it came highly recommended by 2 holistic vets. I have confidence that it will prevent the return of her mammary tumours as these mushrooms have been proven to have healing properties. Time will tell but I have confidence I will return with more positive results.


      The combination of these mushrooms.


      review-checkI would recommend this item to a friend.
    • Verified Buyer

      Great product!

      from Texas on 1/08/2016
      I love Canine CAS Options Extra Strength Immune & Antioxdant and with PureFormulas you will receive your product fast unlike with other companies that carry this item. My vet highly recommends it for my pet so what I look for is price comparison.


      It great


      The cardboard part on the inside of the bottle right at the time your opening the bottle is not exactly secured customer service says its normal.
      review-checkI would recommend this item to a friend.
    • Recommended by my vet.

      from ga on 6/03/2015
      My dog's immune system is not working. She has chronic ear infections and bladder infections. so the vet prescribe Canine CAS Options by Resources. She has been on it for a year now and she just went in for her check up and there are no bladder infections and her ears looked real good.


      It is all natural.


      I don't have anything bad to say about it.
      review-checkI would recommend this item to a friend.
    • Fantastic!

      from Hawaii on 4/25/2015
      Canine CAS Options by Resources has an excellent formulation. Medicinal mushrooms are a must for immune health. Many studies showing their efficacy with cancer and other disease. Very powerful.


      So easy. I used to make my own mix from scratch. Dogs like the taste. I give it after a trick and they think it's a treat.


      review-checkI would recommend this item to a friend.
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Customer Questions and Answers

1-1 of 1

  • Question:
    Can CAS be taken with Yunnan Baiyao Capsules and I'MYunity
    Donna on 10/08/2017 Answer:
    • HI Donna, we do recommend to speak with your veterinarian to know safely and accurately if it is okay for this product to be taken with other supplements.
      PureFormulas on 10/09/2017

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