PhenRX Review (New 2020) – Weight Loss Fact or Fiction?

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  Another week, another weight loss supplement hits the shelves.

At a societal level, we continue to gain weight rapidly. Obesity is at epidemic proportions globally, as are the health implications associated. While losing weight is arguably the best solution to this world wide problem, it is not as easy as it sounds.

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As a result, we continue to look towards weight loss and fat burning supplements to provide that extra kick that will ideally help us lose a few pounds.

Unfortunately, the supplement market is saturated with fat burning supplements that just don’t work. These supplements continue to sell by clever marketing, and promising a quick solution to a serious problem.

Fortunately we are here to help you cut through the misinformation and find what truly works (while also identifying what doesn’t).

One of the most recent weight loss supplements to hit the shelves recently is PhenRX.

What is PhenRX?

PhenRX is a popular weight loss supplement made by the supplement company NexGen.

NexGen is a company that operate out of both Kentucky and Florida. Most of their supplements appear to be made up of low-dose, generic, prescription medications, in addition to weight loss tools, stimulants, and various other dietary supplements.

PhenRX is advertised as a fat burner that utilises a ‘chart topping thermogenic weight loss formulation’, which is suggested to promote rapid weight loss, as well as increase your energy levels and mood.

PhenRX is available as both a weight loss patch, and a pill that is taken orally.

PhenRX is suggested to work by a mechanism somewhat different to most other weight loss supplements, through the deactivation of Alpha-2 receptors. Alpha-2 receptors are found in the adipose tissue of the human body, and help promote the storage of fat within the body.

It is suggested that by deactivating these Alpha-2 receptors, the fat storage process can be disrupted significantly. As a result, fat becomes more accessible as an energy source, and we increase our rate of fat loss considerably.

In addition to deactivating the Alpha-2 receptors, PhenRX also claims to stimulate your metabolism and increase your body temperature, causing an increase in metabolic rate, and further promoting weight loss.

It has also been said that PhenRX can reduce hunger signals, reducing food cravings, and causing a reduction in our daily caloric intake.

These three factors are said to create an optimal fat burning environment within the body.

But does it work?

PhenRX Ingredients

To determine whether or not PhenRX can actually meet these lofty claims, we need to take an in depth look at the ingredients included in PhenRX’s proprietary blend.

1,3,7 Trimethylxanthine

While 1,3,7 Trimethylxanthine  sounds impressive, it is actually one of the most commonly consumed stimulants in the modern world.

That’s right, 1,3,7 Trimethylxanthine is the chemical description of caffeine, so while it may sound fancy, it is just another term used to describe caffeine.

Not that this is a bad thing of course.

Caffeine is a naturally occurring stimulant found in tea, coffee, and the cacao plant. It works by stimulating the brain and central nervous system, reducing feelings of fatigue, while increasing alertness.

Caffeine has also been associated with increases in weight loss.

When consumed, caffeine is quickly absorbed into the blood from the gut, where it is then broken down in the liver, and transported around the body.

Once it reaches the brain, it stimulates the central nervous system. It is this stimulation that increases alertness, reduces fatigue, and stimulates fat loss.

In fact, caffeine consumption has been shown to increase metabolic rate by up to 11%, and fat metabolism by up to 13% [1]. This creates an optimal environment for fat loss, as not only do we increase the amount of energy we burn at rest, we also increase our ability to use fat as a fuel source.

Interstingly, caffeine has also been shown to reduce hunger signals slightly, which can promote weight loss even further.

Synephrine HCL

Synephrine, more commonly known as bitter orange, is a molecule that shares similar mechanisms to the supplement ephedrine. Syniphrine has been used for centuries in traditional eastern medicine, where it was suggested to increase stamina and stave off fatigue.

Scientific research has shown that Synephrine consumption can cause measurable increases in metabolic rate, and fat metabolism [2]. While these are very similar to the effects of caffeine, they actually occur via a different mechanism.

Syniphrine works by inhibiting the fat storage actions of the Alpha-2 receptors found in the adipose tissue of the human body. This causes an increase in the availability of fat to be used for energy, which promotes fat loss.

Syniphrine and caffeine work best when paired together, as they both promote increased metabolic rate and increased fat metabolism, but through different mechanisms.


Schizandrol is an extract from a woody vine that is found in northern parts of china. It has been used in traditional Chinese medicine as a treatment for coughs and asthma.

Schizandrol has been demonstrated improve our ability to respond to stress, such as that seen during vigorous physical activity, or during times of high stimulant intake [3]. This has been suggested to improve immune system function, and increase our ability to manage the side effects associated with high level stimulant use.

Its use in conjunction with caffeine and syniphrine may be beneficial as a way to reduce the negative effects associated high levels of stimulant intakes.

Beta Phenylethylamine

Beta Phenylethylamine is what is considered a trace anime that is found naturally occurring within the human body that can also be taken orally as a supplement.  It has been suggested to influence secretion of the ‘happy hormones’, including both dopamine and serotonin.

As a result it has been suggested to improve mood, and even promote weight loss. Unfortunately, there is limited evidence to support these claims.


Yohimbine is an extract of the Yohimbe tree, an evergreen that is native to Africa. While its bark is said to help improve erectile dysfunction, it has recently gained popularity as a weight loss supplement.

Yohimbine supplementation is suggested to further improve our ability to use fat as a fuel source, through an increase in fat mobilisation. This has been demonstrated through an increase in fat loss in elite soccer players in response to daily Yohimbine supplementation [4].

Again, Yohimbine can be considered synergistic to both caffeine and Syniphrine, and as such should increase fat loss significantly in conjunction with these two supplements.

In Conculsion

While the claims made by PhenRX may seem slightly overstated, there is some evidence to suggest that the ingredients they use may almost meet them.

There are a number of ingredients that promote an increase in weight loss, through both an increase in metabolic rate and fat metabolism, and a mild reduction in hunger signals. These same ingredients may also stave of fatigue, and increase energy and feelings of alertness.

Despite this, it is important to note that most of the ingredients included in this supplement do have stimulant like effects, and may cause jitteriness, and potentially nausea. As such, if you decide to take this supplement, it is best to stay within the recommend dosage, and cease consumption in the presence of any nasty side effects.

Like anything, I truly believe this will work in conjunction with a healthy diet and exercise regime, but won’t be enough to promote significant change by itself!

Related to PhenRX: Phentaslim Review (New 2020) - Why we rate it as #1


1. Acheson, Kevin J., et al. “Caffeine and coffee: their influence on metabolic rate and substrate utilization in normal weight and obese individuals.” The American journal of clinical nutrition 33.5 (1980): 989-997. Viewed at:

2. Stohs, Sidney J., et al. “Effects of p-synephrine alone and in combination with selected bioflavonoids on resting metabolism, blood pressure, heart rate and self-reported mood changes.” Int J Med Sci 8.4 (2011): 295-301. Viewed at:

3. Panossian, A. G., et al. “Effects of heavy physical exercise and adaptogens on nitric oxide content in human saliva.” Phytomedicine 6.1 (1999): 17-26. Viewed at:

4. Ostojic, Sergej M. “Yohimbine: the effects on body composition and exercise performance in soccer players.” Research in Sports Medicine 14.4 (2006): 289-299. Viewed at:



About the Author John Wright

John has been a fitness enthusiast for over 10 years, starting out while struggling with obesity as a teenager. Over the years he has advised numerous clients on how to transform their physiques and their lives. As a writer on Nutrition Inspector he aims to help others achieve real results by staying clear of the common hype and false claims in the supplement industry! You can contact him via the "About Us" page.

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