Pro-RX ThermoLean

It can sometimes be frustrating when your favourite product is discontinued, making it impossible to buy online or in stores. Products can be withdrawn for a number of reasons, from simple and unfortunate factors (like a manufacturer going out of business) to more frightening and concerning reasons (such as a product being found to contain dangerous ingredients).

Below we take an in-depth look at Pro-RX ThermoLean, to see whether this discontinued product was an unfortunate loss to the market or a dodged bullet for potential customers.

Pro-RX ThermoLean Pros

  • Likely to be effective
  • Possibility of bargain prices

Pro-RX ThermoLean Cons

  • Likely to cause severe side effects
  • Unclear list of ingredients
  • Quantities not provided
  • Under FDA warning for lack of quality
Watchdog Rejected Muscle

Pro-RX ThermoLean


What You Need To Know About Pro-RX ThermoLean

Pro-RX ThermoLean is a fat-burning supplement that has been discontinued as of 2017. The formula was originally manufactured by a company called Reaction Nutrition LLC, an American supplement manufacturer that has since changed its name and opened up a new product range. In its Reaction Nutrition days, the company was repeatedly warned by the US Food and Drug Administration (FDA) for poor quality control procedures (such as shipping products with the wrong weights and with insufficient labels). These comments may have led to the product being pulled from shelves sometime between 2012 and 2013.

The actual nature and purpose of Pro-RX ThermoLean is somewhat hard to discern, as we could find various ingredients list for the same product online. Some ingredients lists were for a product that was clearly intended as a sporting supplement and workout aid, and others were for a product that is intended to work as a fat burner. For simplicity, we have reviewed the more common fat-burning version, although readers should be aware that vastly different products with different labels exist under the same generic name of ‘Pro-RX ThermoLean’.

What Are The Side Effects Of Pro-RX ThermoLean?

Pro-RX ThermoLean comes with a number of side effects related to the significant caffeine, synephrine and bioperine content. Caffeine and synephrine tend to interact with one another to cause heart palpitations, jitters, high blood pressure, sleeplessness, fainting, headaches, and (in extreme cases) heart attacks and strokes. Bioperine essentially increases the bioavailability of both, increasing their intensity.

Other side effects from the other ingredients could lead to increased urination, stomach upset, vomiting, diarrhoea, gas, hiccups, itching, drooling, sinus pain, and bloating.

The full list of side effects that could be caused by the ingredients in Pro-RX ThermoLean is extensive, and can be found below under the Side Effects Tab.

How Much Does Pro-RX ThermoLean Cost?

As the product has been discontinued on the Internet, it’s hard to say how much the remaining stocks could cost if found on eBay or a sports supplement shop. When last retailed on the Internet, it seemed to cost roughly $35-$50 depending on pack size.

Our Verdict On Pro-RX ThermoLean

Our best guess for why Pro-RX ThermoLean was discontinued is down to the poor business practices of its manufacturer, Reaction Nutrition. The warning letters sent by the FDA to the company make for worrying reading, painting a picture of a company that produced inconsistent batches of product that were poorly labelled. To this day, you can find more than one ingredient label for a product called ‘Pro-RX ThermoLean’ that is clearly produced by the same company, which makes the whole thing seem unprofessional, poorly thought-out, poorly marketed and poorly understood (even by the manufacturers).

Every indication suggests that product is largely worthless anyway, as this overpowered mix of stimulants and caffeine is as likely to make you sick as make you lose weight. In our view, the dieters of 2017 should count themselves lucky that this product is no longer available to purchase.

We do not recommend Pro-RX ThermoLean to our readers.

Pro-RX ThermoLean Review

Pro-RX ThermoLean is a discontinued fat-burning supplement that was marketed as suitable only for ‘extreme weight loss’. This product was first introduced in 2005 and seems to have fizzled out after an FDA warning in 2012. Since then, it has been discontinued and listed as out of stock on every outlet on the web.

Pro-RX ThermoLean Facts

  • Manufactured by Reaction Nutrition LLC
  • 90 or 120 capsules per container
  • Fat-burning supplement

Although the bottle lists the manufacturer as ‘Pro-Rx Laboratories’, the product was actually produced by Reaction Nutrition LLC. Reaction Nutrition has a troubled history with US regulators, and has been warned in the past for poor quality control procedures, failing to list allergens in their products, and for false advertising. In 2016, Reaction Nutrition merged with a larger company (SDC Nutrition) and has since renamed itself to RecorNation and started afresh with new products.

How to Take Pro-RX ThermoLean

To assess tolerance, begin by taking 1 capsule on an empty stomach 20 minutes before breakfast for the first 3 days, and then an additional 1 capsule 6 hours later starting on day 4. After 7 days, starting on day 8, an additional capsule may be added to the first dose. Under no circumstances should the initial dose be exceeded or the warnings on the bottle ignored. DO NOT USE PRODUCT FOR LONGER THAN 8 WEEKS FOLLOWED BY SUBSEQUENT 4-WEEK BREAK. DO NOT EXCEED 3 CAPSULES IN ANY 24-HOUR PERIOD. To avoid sleeplessness, do not take within 4 hours of bedtime. Consume at least 128 fl. oz of water daily while taking this product.

The newest version of the company can be contacted on their official website, although those looking to make a complaint about Pro-RX ThermoLean may find it difficult to discuss issues related to such an old product (especially one that was released when the company had a different name and head office, etc.).

Pro-RX ThermoLean Concerns:

  • Product is no longer available to buy on the Internet
  • Manufacturer was warned by the FDA over quality control practices
  • Many customer comments complain of side effects

What Does Pro-RX ThermoLean Claim To Do?

ThermoLean is as simple as it gets when it comes to fat burners, simply claiming to ‘increase energy levels, speed up the metabolism and assist in burning fat’. The formula is said to work without inducing side effects such as jitters, and the overall effect of the mix is also said to help with improving focus whilst working out.

Does Pro-RX ThermoLean Work?

Pro-RX ThermoLean contains a number of ingredients that should work in conjunction with one another to boost the consumer’s metabolism and burn fat (if the ingredient quantities are sufficient), although the mix could prove too strong and laden with side effects to achieve the desired results. Although the blend could help to burn fat, many reviewers complain about the number of side effects caused by the supplement, which obviously impacts their ability to take it in the first place!

What Are The Ingredients of Pro-RX ThermoLean?

The ingredients used in Pro-RX ThermoLean are listed below. Readers should note that the individual ingredient quantities used are not listed, as the product consists of a proprietary formula. This can make it difficult to estimate how effective the overall mix is.

One important thing to mention is that very different ingredients lists have been provided for this product on different parts of the Internet, making it very hard for us to determine which one is the ‘real’ one (or how many different versions of Pro-RX ThermoLean there are floating around!) The ingredients list provided below is the one we have seen the most and the one that has been discussed in particular in online customer discussions.

Proprietary Blend (514 mg)

  • Synephrine HCL: A review of numerous studies concluded that use of synephrine resulted in an increase to the participants’ resting metabolic rate and energy expenditure, and moderate weight loss was seen in studies lasting over 6 weeks. However, there are some concerns about its safety being under-researched and the numerous side effects that have been associated with it.
  • Yohimbe HCL: Some studies have noticed increased blood concentrations of free fatty acids in participants who use yohimbe extract, suggesting increased rates of lipolysis. However, the Natural Medicines Comprehensive Database has stated that there is insufficient evidence to claim it aids in weight loss.
  • Caffeine: Numerous studies have shown that caffeine boosts energy levels and alertness, as well as mildly boosting the metabolism. The effects shown in studies are small, and some studies are inconclusive.
  • Guggulsterones: Guggul extract is taken from the sap of a tree native to India. Currently, evidence that Guggul is useful for weight loss is preliminary, with mixed results from the few trials already conducted upon it, with some suggesting that Guggul has no effect upon weight loss, whilst others suggest its effect is moderate.
  • Bioperine: This patented Black pepper extract is used for increasing the bioavailability of nutritional compounds. In other words, it increases the amounts of nutrients that are absorbed into the body in the digestive tract. It may also increase the absorption of various drugs, which may lead to potential side effects.
  • L-Tyrosine: An amino acid that is a building block of protein, this ingredient is found naturally in many foods including meat and dairy products. Some people use it as an appetite suppressant, but there is little evidence that it is effective for this use. Large doses of tyrosine may be useful for increasing alertness, especially in people who are sleep deprived.
  • Chromium Polynicotinate: This is used primarily to lower fasting blood sugar levels and to lower insulin levels in people who have type 2 diabetes. In terms of its potential effect upon weight loss, it is possible that taking chromium picolinate by mouth for 2 to 3 months might produce a small weight loss of about 1.1 kg. This is clearly an incredibly small amount of weight loss, but studies are still inconclusive.
  • Green Tea: Green tea is high in a group of antioxidants called catechins. Studies have suggested that catechins and caffeine both increase energy expenditure by boosting the metabolism temporarily. However, the metabolic increase caused by green tea is limited. One study found that the use of green tea was not enough to counteract weight gain following a high-calorie diet.
  • Dandelion Root: Dandelion is primarily used as a diuretic and laxative.

Does Pro-RX ThermoLean Have Any Side Effects?

Pro-RX ThermoLean comes with a number of strong side effects, and many of the customer comments still available online mention them. Synephrine has been associated with increased heart rates, palpitations, high blood pressure, fainting, and even heart attacks and strokes. Its effects are intensified when mixed with caffeine (as in this product), which itself is associated with jitters, sleeplessness, headaches, heart palpitations, increased urination, and dizziness.

Guggul can cause side effects such as stomach upset, headaches, nausea, vomiting, loose stools, diarrhoea, belching, and hiccups. Guggul can also cause rash and itching, which could be symptoms of an allergic reaction.

Yohimbe can cause a wide range of side effects, including stomach upset, tremors, sleep problems, anxiety or agitation, high blood pressure, a racing heartbeat, dizziness, stomach problems, drooling, sinus pain, irritability, headache, frequent urination, bloating, rash, nausea, and vomiting. High doses can cause more severe effects.

Dandelion is a diuretic, and so could increase urination, and could cause dehydration. Severe dehydration causes other, more serious and unpleasant side effects, and so consumers should ensure that they are drinking plenty of water throughout the day whilst taking this product.

The stimulant effects of Pro-Rx ThermoLean are made stronger with the use of Bioperine, which can increase the absorption of caffeine and other stimulants (increasing their effectiveness, but also making side effects more likely). Bioperine can also affect the absorption of other medications, increasing the chances of an accidental overdose.

KEEP OUT OF REACH OF CHILDREN. Not for use by individuals under the age of 18. Do not use if pregnant or nursing. Consult a physician or licensed qualified health care professionals before using this product. Do not take this supplement if you are at risk for, or have been treated for, or diagnosed with high blood pressure, heart disease, thyroid disease, depression, or other psychiatric conditions renal disease, recurrent headaches, spasms, have asthma or taking asthma medication, are allergic to tyramine, or if you are using a monoamine oxidase inhibitor. Not suitable for anyone who is sensitive to caffeine and other stimulant ingredients.

Are There Any Customer Reviews For Pro-RX ThermoLean?

Pro-Rx ThermoLean has been discontinued for a while, meaning that most review sections are now unavailable to check out. There are still a few message boards and comment sections where we were able to locate a few thoughts on the product; most comments do mention the significant side effects associated with ThermoLean, although some still insisted that they liked the benefits it offered.

I used Thermolean in the ’90s and it worked amazingly! After I had my two kids, I would use it and it really curbed my appetite and I lost weight. No side effects whatsoever, just a little jittery from the caffeine but well worth it! I am looking into taking it again.

Most amazing fat burner.

It was good to lose weight only took one for the first while and when I moved onto two I had increased heart rate dizziness vomiting and sleeplessness.

Thermolean is the worst product one can use for weight loss… I only tried 1 capsule of ThermoLean and could feel all the side effects like sleeplessness, heart beat rate, feeling of vomiting, chest pain… Thermolean will show side effects 110% sooner or later.

Does Pro-RX ThermoLean Offer a Money-Back Guarantee?

The company that once manufactured Pro-RX ThermoLean (Reaction Nutrition) has since moved on to other things. The product has been discontinued and the entire company has since undergone a merger and name change. Anyone looking to return a pack of Pro-RX ThermoLean at this point may be out of luck, although they could try contacting the outlet where they bought the product from.

Where Can I Buy Pro-RX ThermoLean?

Pro-RX ThermoLean has long been discontinued, and is no longer available to buy on the Internet. You may be able to find a forgotten pack somewhere in a gym supply store or sporting supplement shop, although we strongly advise checking the ‘best before’ date before purchasing (we estimate that the product was discontinued sometime around 2013!)

Summary: Pro-RX ThermoLean

Image not available at this time

3.5 out of 5
Editor's Rating
  • Effectiveness
  • Safety
  • Price / Guarantee

Top Performing Supplements 2021

Hunter Test
MAN Sports Beta-Alanine
Product Phentaslim Hunter Test MAN Sports Beta-Alanine
Review Watchdog Review Watchdog Review Watchdog Review
Purpose Cutting body fat, endurance, thermogenesis. Testosterone booster. Pre-workout, endurance.
Clinically Proven Ingredients
Clinically Proven Ingredients
Customer Support
Customer Support
Money-back Guarantee
Money-back Guarantee
Free Shipping
Free Shipping

Disclaimer: Our reviews and investigations are based on extensive research from the information publicly available to us and consumers at the time of first publishing the post. Information is based on our personal opinion and whilst we endeavour to ensure information is up-to-date, manufacturers do from time to time change their products and future research may disagree with our findings. If you feel any of the information is inaccurate, please contact us and we will review the information provided.

Have Your Say

Add your comment

We'd love to get your opinion. Please keep it clean and stay on topic, no spamming. Comments are moderated before being made live. Your email address will not be published.
We cannot give advice about medical conditions or prescription drugs. Please direct specific medical questions to your doctor.

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Get the conversation started by leaving your comments using the form above.