Synedrex 2017: Another Abominable Prop Blend from Metabolic

Metabolic Nutrition Synedrex

Metabolic Nutrition has revamped their flagship fat burner Synedrex to include DMHA and Eria Jarensis.

After having a blow dealt to them by the FDA (as well as Hi-Tech Pharma cloning the OG Synedrex with their Synadrene), Metabolic Nutrition is swinging back!

Thanks to their success with the past two versions of Synedrex, Metabolic’s garnered quite a reputation as one of the premier manufacturers of fat burners on the market. But we’re not sure how much longer that’s going to last.

The brand is back in the headlines as they’ve finally revamped their flagship Synedrex fat burner to include DMHA and “Eria Jarensis” in place of the previous generation stimulants that was once included in the formula (or AMP Citrate that was in the ill-fated second version!)

It was only a matter of time before we got a DMHA version, and here it is – and boy is it a disappointment!

We’ve covered them a time or two before on the blog, most recently when discussing their newest thermogenic supplements, Stimukal and ThermoKal. The former seemed decent enough, but the latter… not so much. Much in the same vein as ThermoKal’s highly-questionable proprietary formula, this prop blend leaves us completely scratching our heads as well.

All the details are just ahead, but before we get there, take a moment to check the best deal and sign up for alerts from PricePlow:

Metabolic Nutrition Synedrex – Deals and Price Drop Alerts

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Note: In the price comparisons above, you will need to check to make sure you’re getting the version you want. The new version we’re writing about here will have a label that says “2-aminoisoheptane” on it, so hopefully you can find the older versions that weren’t so poorly-conceived.

Synedrex New Formula 2017 Ingredients

As we’ve seen with other recent Metabolic Nutrition fat burners, Synedrex is a massive prop blend of ingredients commonly found in other fat burners on the market.

While the profile looks good, we have no clue how much caffeine or any other ingredient is in here! And there’s a huge question mark regarding why yohimbine is so high in the label!

Note: Doses listed below are based on 1 serving (i.e. 1 capsule).

  • Proprietary Blend (614mg)

    • Caffeine Anhydrous

      Synedrex New Formula Ingredients

      The new Synedrex Ingredients is proof why poorly-designed proprietary blends are bad for consumers. Why is yohimbine HCl so high up here? Either everything behind it is pixie dusted, or it’s going to give someone a panic attack of epic proportions. And what’s that last parenthesis closing??? And don’t miss the “gelatin” misspelling!

      Like all good fat burners, Synedrex contains the oldest stimulant around — caffeine anhydrous. It provides a solid increase in energy, focus, and alertness, as well as enhancing lipolysis in the body. But, as we stated above, we’re not sure how much caffeine is in here. It could be 150mg or 300mg, we honestly don’t know, and that’s an issue we don’t like. Maybe Metabolic will disclose it.

    • 2-aminoisoheptane

      Here’s one of the newest additions to Synedrex to replace the previous stimulants in the last version that got busted by the FDA — neither are obviously no longer included.

      2-aminoisoheptane, a.k.a. DMHA, is an aliphatic amine that’s not as potent as its predecessor. It brings a significant mood-enhancing effect to Synedrex and should help give a feeling of euphoria, especially when paired with the next ingredient.

      At the time, not a ton of fat burners have picked it up, so this was a unique play for Metabolic.

    • Eria Jarensis

      Eria Jarensis is a plant loaded with PEA-based compounds including N-methyl-PEA, N,N-dimethyl-PEA, and N-phenethyl dimethylamine.[2] Chances are, when you see eria jarensis, you’re probably getting primarily those compounds, but the label really should say exactly what they’re standardizing their “extract” for.

      Eria is known for its distinct euphoric feeling that lasts considerably longer than regular PEA due to the different molecular structure.

      You should be feeling really, really good on Synedrex if there’s a decent dose of these PEAs in here, but, as we’ve stated a few times already, we’re not sure how much is included.

      You can read more on our post titled Eria Jarensis Extract / N-phenethyl dimethylamine: The Next Big Thing?

    • Paradoxine

      Metabolic Nutrition Synedrex Girl

      She may be all smiles over the re-release of Synedrex, but we’re not excited about this prop blend.

      Paradoxine is the leading Grains of Paradise extract on the market for increasing thermogenesis, energy expenditure, and enhancing fat utilization form Brown Adipose Tissue (BAT).[3] This is one of the few non-stimulant ingredients that actually works well, and that’s why it’s our favorite stim-free ingredient!

      For additional information on this potent thermogenic agent, check out our mega-post titled Grains of Paradise: Fat Fighting Spice of the Goddesses, but you’ll be happy to know that Paradoxine is our preferred form of it because it uses standardizations that are backed by research.

    • Bitter Orange [Citrus Aurantium] Extract

      Another fat-fighting plant is Bitter Orange (Citrus Aurantium) loaded with all sorts of potent beta-2 agonists that stimulate lipolysis in the body. Synedrex is standardized for N-methyl tyramine, octopamine, and synephrine, which all serve to enhance the body’s natural fat burning abilities as well as energy and focus.[4,5,6]

    • Yohimibine HCl

      Found in just about every fat burner on the market, yohimbine is a great ingredient for eliminating those areas of “stubborn fat.” Yohimbine functions as an alpha-2-adrenergic blocking agent that boosts noradrenaline and prevent your body from storing fat.[7] Additionally, it can increase energy expenditure, ramp up lipolysis and suppress appetite.[8,9,10,11]

      WARNING: Crazy high dose here, or are the next ingredients pixie dusted??

      Issue here is that we’re looking at yohimbine here, not yohimbe — yohimbine is extracted from yohimbe. Normal doses of yohimbine are usually around 2.5mg, but can go up to 10mg in more hardcore modes (which may be very unpleasant for some individuals).

      This means that we’re getting either way too high of a dose of yohimbine here, or the following ingredients are dosed too low.

      Just like in Metabolic’s ThermoKal, these proprietary blends are showing potentially borderline dangerous things and they really need to start opening up their formulas.

    • Higenamine

      Metabolic Nutrition Synedrex Hands

      All hands on deck, the new Synedrex is here!

      Also known as Norcoclaurine, higenamine is another strong beta-2 agonist that increase the body’s ability to burn stored fat for fuel.[12] Similar to the other beta agonist previously discussed, Higenamine likewise increases noradrenaline production, which further enhances “fight or flight” response yielding increased energy and alertness.

      Usually we like somewhere from 25-50mg of this ingredient. Given that it’s behind yohimbine, that’s likely impossible (or the yohimbine would damn near kill you), so it’s unlikely this is dosed well.

    • Hordenine

      Yet another beta agonist found in Citrus Aurantium is Hordenine, which acts as a bronchodilator (relaxes bronchial passages) and enhances vasodilation.[13]

      More importantly, Hordenine also acts as a noradrenaline reuptake modulator[14,15], thereby preserving the effects noradrenaline in your body which results in significantly greater energy and focus.

      Another dose that can’t be good enough due to it being behind yohimbine HCl.

    • Huperzine

      A powerful focus boosting agent, Huperzine sustains the actions of acetylcholine (the “learning neurotransmitter”) by inhibiting the enzyme which degrades acetylcholine in the body, acetylcholinesterase.[16]

      Huperzine also supports brain health, by defending against glutamate, the neuron death molecule, and possibly encouraging the generation of new brain cells.[17,18]

    • N-methylphenethylamine

      Metabolic Nutrition Synedrex Solution

      Is Synedrex your one pill solution for weight loss? We’re inclined to disagree strongly.

      N-methylphenetylamine (NMPEA) is another PEA containing molecule that can serve to enhance your overall mood and alertness. It’s naturally-occurring in trace amounts in the human body and also found in a number of plants, including Acacia Rigidula.[19]

      For the low down on Acacia, check out our in-depth post: BMPEA, Acacia Rigidula, GNC Lawsuits, and the FULL Story.

      Once again, we have to wonder how much is in here if it’s after yohimbine.

    • L-Dopa

      Synedrex Ingredient Mistakes

      There are three left/opening parenthesis but four right/closing parenthesis in this label. What did they REALLY mean here? We think we’ll pass on putting your stimulant chemicals into our body this time around….

      Talk about a feel good fat burner. We’ve got another mood-boosting compound in L-Dopa… if the dose is high enough?

      L-Dopa is a precursor to dopamine , norepinephrine, and epinephrine that can cross the blood-brain barrier (something dopamine can’t), which when supplemented serves to enhance mood and focus.[20]

      Sorry to sound like a broken record, but… how much can there really be here at this point, if it’s behind yohimbine?

      More label questions / concerns: parenthesis game is broken

      Also, in the ingredient label, there is an additional closing/right parenthesis after this ingredient that isn’t really valid. What is it closing? Is there a prop blend inside of this prop blend that we can’t understand because of mislabeling?

    • Poly-Thyronine

      Poly-Thyronine is a combo of two T2 thyroid hormone metabolites. These are naturally occurring compounds in the human body, and help increase your metabolic rate and decrease your appetite without impacting heart rate, or blood pressure.[21,22,23]

  • Synedrex Other Ingredients Gelain

    So many errors we couldn’t even spot them all. Credit to Seth D. on Facebook for this one.

    More gaffes in the “Other Ingredients” section

    Finally, let’s not miss the misspelling of the word “gelatin” in the “Other Ingredients” area!! Unless “Gelain” is something new we’ve never heard of.

    Credit to Seth Davis on Facebook for catching this one!


Metabolic Nutrition recommends assessing your tolerance by taking 1 capsule in the morning with food. Do not use more than 1 capsule daily and within 12 hours of bedtime.

Metabolic Nutrition Synedrex Joke

It’s no joke Synedrex is back, the only thing that is a joke is its formula

Takeaway: Metabolic needs to stop it with the prop blends

Seriously, what happened to Metabolic? ThermoKal and its possibly-high-proprietary-dose-of-berberine could possibly injure someone as labeled, and this either has enough yohimbine to kill a horse or it has at least three pixie-dusted ingredients. And we still don’t know caffeine.

Sorry folks, but we’re not touching this one. Not until some of this mess is clarified.

There’s something seriously wrong here. Did they mean to say yohimbe instead of yohimbine? If so, that might make at least a little sense. Until further notice, we’ll steer clear.

Metabolic Nutrition Synedrex – Deals and Price Drop Alerts

Get Price Alerts

No spam, no scams.

Disclosure: PricePlow relies on pricing from stores with which we have a business relationship. We work hard to keep pricing current, but you may find a better offer.

Posts are sponsored in part by the retailers and/or brands listed on this page.

About the Author: Mike Roberto

Mike Roberto

Mike Roberto is a research scientist and water sports athlete who founded PricePlow. He is an n=1 diet experimenter with extensive experience in supplementation and dietary modification, whose personal expertise stems from several experiments done on himself while sharing lab tests.

Mike's goal is to bridge the gap between nutritional research scientists and non-academics who seek to better their health in a system that has catastrophically failed the public.

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  2. Hedman, K; Phenethylamines from Eria Jarensis Ames; Acta Chemica Scandinavica, Volume 23; 1969; Retrieved from
  4. Stohs SJ, Preuss HG, Shara M. A Review of the Receptor-Binding Properties of p-Synephrine as Related to Its Pharmacological Effects. Oxidative Medicine and Cellular Longevity. 2011;2011:482973. doi:10.1155/2011/482973.
  6. Ratamess NA, Bush JA, Kang J, et al. The effects of supplementation with P-Synephrine alone and in combination with caffeine on resistance exercise performance. Journal of the International Society of Sports Nutrition. 2015;12:35. doi:10.1186/s12970-015-0096-5.
  7. Szemeredi K, et al; Simultaneous measurement of plasma and brain extracellular fluid concentrations of catechols after yohimbine administration in rats . Brain Res. (1991)
  8. Mizuki Y, et al; Differential effects of noradrenergic drugs on anxiety and arousal in healthy volunteers with high and low anxiety . Prog Neuropsychopharmacol Biol Psychiatry. (1996)
  9. Galitzky J, et al; Alpha 2-antagonist compounds and lipid mobilization: evidence for a lipid mobilizing effect of oral yohimbine in healthy male volunteers . Eur J Clin Invest. (1988)
  10. Callahan MF, Beales M, Oltmans GA; Yohimbine and rauwolscine reduce food intake of genetically obese (obob) and lean mice . Pharmacol Biochem Behav. (1984)
  11. Waluga M, et al; Cardiovascular effects of ephedrine, caffeine and yohimbine measured by thoracic electrical bioimpedance in obese women . Clin Physiol. (1998)
  13. Frank M, et al; Hordenine: pharmacology, pharmacokinetics and behavioural effects in the horse; Equine Vet J. (1990)
  14. Barwell C.; School of Pharmacy; “Deamination of hordenine by monoamine oxidase and its action on vasa deferentia of the rat;” 1989
  15. Nedergaard O.; British Journal of Pharmacology; “Action of various sympathomimetic amines on the isolated stripped vas deferens of the guinea-pig;” November 1968
  16. Zhao, Q; Effects of huperzine A on acetylcholinesterase isoforms in vitro: comparison with tacrine, donepezil, rivastigmine and physostigmine.; State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences; 2002
  17. Ved, H; Huperzine A, a potential therapeutic agent for dementia, reduces neuronal cell death caused by glutamate.; Division of Biochemistry, Walter Reed Army Institute of Research; 1997
  18. Ma, T; Huperzine A promotes hippocampal neurogenesis in vitro and in vivo.; State Key Laboratory of Biomembrane and Membrane Biotechnology, School of Life Sciences, Tsinghua University; 2013
  19. Pendleton RG, Gessner G, Sawyer J. Studies on lung N-methyltransferases, a pharmacological approach. Naunyn Schmiedebergs Arch Pharmacol. 1980;313(3):263-268.
  22. Lombardi, A, et. al; The Biochemical Journal; Effect of 3,5-di-iodo-L-thyronine on the mitochondrial energy-transduction apparatus; February 1998
  23. Lanni, A, et. al; FASEB Journal; 3,5-Diiodo-L-thyronine powerfully reduces adiposity in rats by increasing the burning of fats; September 2005