RX Vitamins

Rx D3 Forte

$48.29

  • Supports healthy Vitamin D levels when supplementation is needed
  • Supports normal calcium and phosphorus nutritional balance
  • Provides higher-concentration support for veterinarian-directed Vitamin D needs
  • Authentic products from trusted brands
  • Free shipping on all consumer purchases
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DESCRIPTION

Palatable Source of Pure Cholecalciferol

Rx D3™ Forte contains cholecalciferol, the precursor to Vitamin D3 for all animals. The cholecalciferol is blended with MCT oil. The cholecalciferol is blended with MCT oil at a higher concentration than the standard Rx D3. This provides 5 times the potency per drop to better suit the needs of the severely vitamin D3 deficient patient, the larger patient, or any other patient that would benefit from a higher concentration. Rx D3 Forte comes with a glass graduated dropper to facilitate accurate serving size.
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Rx D3 Forte is a liquid Vitamin D3 (cholecalciferol) supplement for dogs and cats, made by Rx Vitamins with an MCT oil base for palatability. It delivers five times the potency per drop of the standard Rx D3, suited for pets needing higher Vitamin D3 support, larger pets, or veterinarian-directed dosing. A glass graduated dropper allows precise, consistent serving. Talk to your veterinarian to determine if this higher-concentration formula is right for your pet. 

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Helpful product information

Frequently Asked Questions

Clear answers to help you choose and use this product with confidence.

What are Rx D3 and Rx D3 Forte used for?

Rx D3 and Rx D3 Forte are Vitamin D3 supplements designed to support healthy Vitamin D levels in pets. They provide a palatable source of cholecalciferol (Vitamin D3) to support overall pet wellness when supplementation is needed.

Which pets can use Rx D3 and Rx D3 Forte?

These supplements are formulated for all animals. They are designed to support pets that require Vitamin D3 supplementation as recommended by a veterinarian.

What is the key ingredient in these Vitamin D3 supplements?

The active ingredient is Cholecalciferol (Vitamin D3). Rx D3 is blended with virgin olive oil, while Rx D3 Forte uses MCT oil and provides a higher concentration of Vitamin D3 per drop.

What is the difference between Rx D3 and Rx D3 Forte?

Rx D3 Forte provides a higher concentration and 5 times the potency per drop compared to the standard formula, making it suitable for larger pets or pets requiring higher Vitamin D3 support.

How long does shipping take, and is shipping free?

Consumer orders ship free with no minimum purchase and typically arrive within 3–5 business days. Wholesale orders qualify for free shipping on purchases over $300. Tracking information is emailed as soon as your order ships, so you can follow its delivery progress.

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High-Potency Liquid Vitamin D3 for Dogs and Cats

Rx Vitamins Rx D3 Forte is a concentrated liquid vitamin D3 supplement formulated for dogs and cats that require veterinarian-guided vitamin D support. The formula provides cholecalciferol in an MCT oil base and delivers 500 IU of vitamin D3 per drop.

Rx D3 Forte provides five times the potency per drop of standard Rx D3, making it a higher-concentration option for larger pets or animals whose veterinarian recommends a stronger vitamin D3 formula.

The 2 fl oz bottle includes a graduated glass dropper to support accurate administration.

500 IU Vitamin D3 per Drop

Each drop of Rx D3 Forte provides 500 IU of vitamin D3 as cholecalciferol.

The concentrated formula contains 15,000 IU per 1 mL.

Because the product is highly concentrated, serving amounts should be determined with veterinary guidance.

What Is Cholecalciferol?

Cholecalciferol is vitamin D3, a nutrient involved in normal calcium and phosphorus balance and overall nutritional health.

Rx D3 Forte provides cholecalciferol in a concentrated liquid form designed for canine and feline patients requiring additional vitamin D3 support.

Five Times the Potency of Standard Rx D3

Rx D3 Forte delivers approximately five times the vitamin D3 potency per drop compared with standard Rx D3.

This higher concentration can make the Forte formula more practical for larger pets or when a veterinarian recommends a higher vitamin D3 intake.

MCT Oil-Based Liquid Formula

Rx D3 Forte blends cholecalciferol with MCT oil.

The liquid oil-based format allows the vitamin D3 to be administered in accurately measured drops using the included graduated dropper.

Rx D3 Forte for Dogs

Rx D3 Forte is formulated for dogs that require veterinarian-directed vitamin D3 supplementation.

The high-concentration formula can be particularly useful when a larger dog or another canine patient requires more vitamin D3 per measured drop than the standard Rx D3 formula provides.

Do not determine the serving amount based on body weight alone. Vitamin D status and veterinary recommendations should guide supplementation.

Rx D3 Forte for Cats

Rx D3 Forte is also formulated for cats.

Because each drop contains 500 IU of vitamin D3, feline supplementation should be carefully measured and used under veterinary guidance.

Why Test Vitamin D Before Supplementing?

The current product directions recommend vitamin D testing to help establish a safe and appropriate serving amount.

Testing gives your veterinarian objective information about your pet's vitamin D status before deciding how much supplemental vitamin D3 may be appropriate.

Follow-Up Vitamin D Testing

The current label also recommends follow-up testing after supplementation begins.

Retesting can help your veterinarian determine whether vitamin D status has reached the intended range and whether the serving amount should remain the same or be adjusted.

Rx D3 Forte vs. Rx D3

Rx D3 and Rx D3 Forte both provide vitamin D3 as cholecalciferol, but they differ in concentration and carrier oil.

Rx D3 Forte uses MCT oil and provides 500 IU per drop, delivering five times the potency per drop of the standard formula.

Rx D3 uses virgin olive oil and provides a lower concentration designed to allow more flexible administration for smaller animals.

Your veterinarian can help determine which concentration is appropriate based on your pet's vitamin D status and individual needs.

2 fl oz / 60 mL Bottle

Rx D3 Forte is supplied in a 2 fl oz / 60 mL bottle with a graduated glass dropper.

The dropper helps provide accurate measurement when following a veterinarian-directed supplementation plan.

Important Vitamin D3 Safety Considerations

Vitamin D3 is a concentrated nutrient, and excessive intake can be harmful.

Use Rx D3 Forte only according to the current product label and your veterinarian's recommendations.

In case of accidental overdose, contact a veterinarian or health professional immediately.

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

Choosing Between Standard and High-Potency Vitamin D3

When comparing vitamin D3 supplements for pets, consider the vitamin D3 concentration, amount per drop, carrier oil, species labeling, measuring method, laboratory results, and veterinary recommendations.

Rx D3 Forte provides 500 IU per drop in an MCT oil-based liquid, making it the higher-concentration option within the Rx D3 line.

Rx Vitamins Rx D3 Forte

Rx Vitamins Rx D3 Forte is a high-potency liquid vitamin D3 supplement for dogs and cats that provides 15,000 IU of cholecalciferol per mL and 500 IU per drop.

The MCT oil-based formula provides five times the potency per drop of standard Rx D3 and includes a graduated glass dropper for accurate veterinarian-guided administration.

For pet owners searching for Rx D3 Forte, vitamin D3 drops for dogs and cats, or a higher-concentration liquid cholecalciferol supplement, Rx D3 Forte provides a clearly defined veterinary nutritional option.