Your Cart is Empty
But it doesn't have to be.
Continue Shopping.
Added to Cart
Cart Total:
Customers Also Bought:

Thorne Research, Thyrocsin, Thyroid Cofactors, 120 Veggie Caps

Our Price:
You Save:
$0.01 (0)
Earn 5% Loyalty Credit ?

Sorry, this product is no longer in stock.

This product is already in your Wish List.

View Wish List

This product is now in your Wish List.

View Wish List
In Stock
  • Expiration Date: Oct 2018
  • Shipping Weight:
    0.3 lbs
    Switch to Metric units
  • Product Code: THR-78401
  • UPC Code: 693749784012
  • Package Quantity: 120 Veggie Caps
  • Dimensions:
    2.2 x 2.2 x 4.4 in, 0.25 lbs
    Switch to Metric units
Bundle Offer
Save $2.00 when you purchase these items today for only $32.14
Total: $34.14
Combo Discount: - $2.00
Together: $32.14

Sorry, this product is no longer in stock.

Product Overview


  • Dietary Supplement
  • Hypoallergenic
  • For Nutritional Support of Thyroid Function
  • Contains Nutrients and Botanicals That Enhance T4 Production
  • Provides Key Nutrients for Peripheral Conversion of T4 to T3
  • Helps Optimize Metabolism
  • Unique, Non-Glandular Formulation Available Only from Thorne Research

The hormones thyroxine (T4) and triiodothyronine (T3) are produced by the thyroid gland. These hormones are essential to the proper development of cells in the body. Thyroid hormones regulate the metabolism of proteins, fats, and carbohydrates, affecting how these compounds produce energy. Individual thyroid hormones have important functions in the body; for example, T4 supports cardiac output, heart rate, respiratory rate, and basal metabolic rate (BMR). A low BMR may cause one to be fatigued, chilly, and have trouble losing weight.

Thyrocsin provides supportive nutrients for a healthy thyroid gland. Not only does Thyrocsin support healthy thyroid function, it also provides nutrients necessary for conversion of T4 to T3 in the tissues outside the thyroid gland.

Iodine is necessary for formation of T4, while L-tyrosine is a necessary component of both T4 and T3 formation. Animal studies indicate the Ayurvedic botanical ashwagandha can increase T4 concentrations. Several nutrients are also necessary for conversion of T4 to T3, including the minerals selenium, zinc, and copper. Thyrocsin contains vitamin B12 because its insufficiency appears to interfere with the activity of thyroid hormones. Conversion of T4 to T3 can be inhibited by heavy metal toxicity and lipid peroxidation; the antioxidant vitamins C and E can counterbalance this inhibition.

Thyroid hormones are involved with metabolism throughout the body. Thus, a deficiency or excess of thyroid hormones can have far-reaching effects. High cortisol levels can interfere with thyroid function, resulting in low T4 or poor conversion of T4 to the active form, T3. Nutrients that support normal levels of cortisol may be of benefit for this population.

Suggested Use

Take 2 capsules two times daily or as recommended by a health-care practitioner.

Other Ingredients

Hypromellose (derived from cellulose) capsule, leucine, silicon dioxide.

This product is contraindicated in an individual with a history of hypersensitivity to any of its ingredients.

This product does not contain wheat, gluten, corn, yeast, soy, egg, dairy products, or artificial colors, sweeteners, or flavors. This product also does not contain lactose, palmitic acid, or magnesium, calcium, or vegetable stearates.

Iodine may occasionally cause an allergic reaction in some individuals.


Tamper Evident: Use only if bottle is sealed. Store tightly sealed in a cool, dry place.

If pregnant, nursing, or trying to conceive, consult your health-care practitioner before using this product.

Supplement Facts
Serving Size: Two Capsules
Servings Per Container: 60
  Amount Per Serving %Daily Value
Vitamin C (as Ascorbic Acid) 200 mg 334%
Vitamin E (as d-Alpha Tocopheryl) 100 IU 334%
Vitamin B12 (as Methylcobalamin) 100 mcg 1,666%
Iodine (as Potassium Iodide) 225 mcg 150%
Zinc (as Zinc Picolinate) 5 mg 33%
Selenium (as Selenium Picolinate) 100 mcg 143%
Copper (as Copper Picolinate) 500 mcg 25%
L-Tyrosine 500 mg *
Ashwagandha extract (root) (Withania somnifera) 150 mg *
*Daily Value (DV) not established.
iHerb Customer Reviews

New Product for my daughter who is 9yrs

Posted by 5163288688297141300 on Feb 21, 2017

My daughter has Hypothyroidism. I have taken her off synthetic medication and trialling her naturally. She hasn't really been on this product long enough for me to say whether or not it is good or not. Time will tell. On the plus side. She hasn't had any side effects at all.

Verified Purchase

Was this review helpful to you?

Thanks for your feedback!

Thyroid stable

Posted by hanafeng on Dec 01, 2016

There is spirit Still looking forward to better results

Verified Purchase

Was this review helpful to you?

Thanks for your feedback!

Wow! my thyroid is not a problem anymore.. (now it's my sugar, but no worries about thyroid)

Posted by 5764471808898344877 on Nov 30, 2016

I had read reviews and researched the content of these caps but I was surprised by the effect. I found myself energized and able to do things and even to exercise. I actually ran to catch a bus and was not winded as I would usually be. Best of all, my test results were very good. I have a hypothyroid problem. But my T4 levels are now in the normal range. my TSH is now too low (hyper) but my doc thinks it will normalize. I will continue taking this for a few more months and hopefully i will be able to lose the weight and normalize my levels. Excellent product. I noticed no side effects. I slept well and had no jittery feelings. I was taking Synthroid as well as a teaspoon of a royal jelly, bee pollen, and propolis mix every day; in addition to the 2 pills of thyrocsin twice per day. Very good product.

Verified Purchase

Was this review helpful to you?

Thanks for your feedback!

Thyroid Cofactors

Posted by Sydney13 on Oct 31, 2016

I think this is working but have not been on it long enough. I will report back when I finish this first bottle but so far- so good.

Verified Purchase

Was this review helpful to you?

Thanks for your feedback!

Great results, yr thyroid will love it.

Posted by 4642430399502877602 on Oct 26, 2016

Found this product really helped. I was told that: I do and I don't have thyroid problems with my Free T3 and Reverse T3 (by 2 Doctors). This product raised my basel body temp back up again. (refer info on temperature in Wilsons Temperature Syndrome). I don't believe all you read or hear about these type of products but the proof is in how much better I feel with taking this product. My TSH for my thyroid always was in the good range but blood TSH is too inaccurate. Try this product, I am sold on it. Blood tests only measure whats in the blood and not whats in your cells. Helpful to have a HTMA test done ( Hair Tissue Mineral Analayis) too. best wishes. Ingrid. Melbourne.

Verified Purchase

Was this review helpful to you?

Thanks for your feedback!