Vitamin C (ascorbic acid) plays a fundamental role in mammalian health: it is essential for collagen synthesis, immune cell function, iron absorption, and acts as a primary water-soluble antioxidant. While dogs and cats can synthesize their own vitamin C endogenously, this capacity becomes insufficient under conditions of high oxidative stress — illness, surgery, chronic inflammation, cancer, or intensive physical activity. In these situations, supplemental vitamin C provides a meaningful therapeutic benefit that endogenous synthesis cannot match.
Rx Vitamins Bio-C Powder delivers buffered ascorbic acid in a convenient powder format that mixes easily into food. The buffered form (ascorbate rather than pure ascorbic acid) is gentler on the GI tract, reducing the risk of loose stools that can occur with high doses of unbuffered vitamin C. This is particularly important in dogs with sensitive digestive systems or those simultaneously managing GI disease.
Bio-C is used as a stand-alone immune and antioxidant support supplement and as part of multi-supplement protocols for dogs and cats managing cancer, infectious disease, or post-surgical recovery. The powder format accommodates flexible dosing across a wide range of body weights. Each 113 g jar provides an economical supply for ongoing supplementation.
- Buffered ascorbate — reduces GI irritation compared to unbuffered vitamin C
- Powder format — easy to mix into food, precise dosing by weight
- Supports collagen synthesis, immune function, and antioxidant defence
- Useful during illness, recovery, cancer management, and high-stress situations
- 113 g jar — economical supply for ongoing use
Key Ingredients
Buffered vitamin C (ascorbate) — the mineral salt form of ascorbic acid; provides identical antioxidant and immune activity with better GI tolerability at higher doses.
Directions for Use
Dose by body weight as directed by your veterinarian. Mix thoroughly into wet or dry food. Start with a lower dose and increase gradually to assess GI tolerance.
Supplement Advisor's Note
In oncology patients, high-dose vitamin C is sometimes discussed as a complementary therapy. At the oral doses achieved with a powder supplement, the primary benefit is antioxidant and immune support — not the pro-oxidant effects seen with intravenous high-dose protocols in human oncology. For pets receiving doxorubicin or other anthracycline chemotherapy, there has been historical debate about whether antioxidants interfere with treatment; current veterinary oncology opinion generally supports antioxidant supplementation at physiological doses. Always discuss with your oncologist.
Frequently Asked Questions
- Do dogs and cats need supplemental vitamin C if they make their own?
- Healthy animals on a complete diet typically don't. During illness, surgery, heavy exercise, or chronic disease, endogenous production becomes insufficient and supplementation provides measurable support.
- What does "buffered" mean on the label?
- Buffered vitamin C is ascorbate — ascorbic acid neutralized with a mineral (typically calcium or sodium). It's less acidic, making it gentler on the stomach at higher doses.
- Can high doses of vitamin C cause diarrhea in dogs?
- Yes, unbuffered vitamin C can cause loose stools at higher doses due to osmotic effects in the colon. The buffered formulation in Bio-C significantly reduces this risk.
- Is this product suitable for cats?
- Yes, with appropriate weight-based dosing. Cats are less likely to need supplemental C than dogs but benefit in similar high-stress situations.
- Can I give this alongside other antioxidant supplements?
- Generally yes. Vitamin C works synergistically with vitamin E. Inform your vet of the full supplement protocol to avoid unintentional over-supplementation.
