Mega High Stim Preworkout PRE WORKOUT - Primeval Labs
Mega High Stim Preworkout PRE WORKOUT - Primeval Labs
Mega High Stim Preworkout PRE WORKOUT - Primeval Labs
Mega High Stim Preworkout PRE WORKOUT - Primeval Labs
Mega High Stim Preworkout PRE WORKOUT - Primeval Labs

Mega High Stim Preworkout

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You loved it before and now it is back! Mega High Stim Preworkout has returned bigger and better than ever!

What is Mega High Stim Preworkout?

Mega takes the best elements from the original you loved so much and took it to a whole new level.

With Mega you get all of the same great pumps and performance of the original, but now you get more focus and an even better level of flavor!*

You asked for the best, and Primeval Labs has delivered with Mega High Stim Preworkout!*


L-Citrulline (6,000mg)

 L-Citrulline is a nonessential amino that supports nitric oxide production by increasing plasma levels of L-Arginine, the amino acid that serves as the substrate (“fuel”) for nitric oxide production.*

L-Citrulline offers a high degree of bioavailability than L-Arginine. [3] Furthermore, Citrulline has also been shown to be a better supplement for increasing plasma arginine levels than even L-arginine itself!*

In the end, L-Citrulline is a better option for those looking to boost nitric oxide production.*

With greater NO production comes greater blood flow along with additional oxygen and nutrient delivery to your muscles, supplying them with the necessary nutrients to perform optimally.*

Additional L-Citrulline research indicates it may enhance Vo2 kinetics as well as ATP production, promoting greater endurance and athletic performance as well as lean body mass! [4,5,6,7]*

Beta Alanine (3,200mg)

Beta alanine is a powerful amino acid that helps increase stamina and endurance by increasing muscle concentrations of carnosine. [8,9,10,11,12]*

Carnosine is a powerful intracellular buffer that helps eliminate acidic ions that accumulate during the course of repeated muscle contractions. These acidic ions contribute to the “burning” sensation you feel during training, which induces feelings of fatigue.*

But, this acidic ion build up also inhibits a muscle’s ability to repeatedly contract. Eventually, too many of these ions accumulate, and muscles will no longer contract.*

By increasing intramuscular concentrations of carnosine (via beta alanine supplementation), muscles’ ability to buffer these acidic ions is enhanced, allowing for more work to be completed before fatigue sets in.*

Betaine (2,500mg)

Betaine (trimethylglycine) is a compound that’s found in beets and other plants.* 

Over the past few years, betaine has received increased interest among athletes due to the results of several studies (conducted in humans) which note betaine supplementation may boost muscle endurance and increase strength.*

Betaine supports endogenous creatine production, via methylation of the amino acid homocysteine to methionine (a building block of creatine). Additionally, betaine also functions as a powerful osmolyte in skeletal muscle, which encourages muscle cells to absorb extra water, supporting improved hydration and stamina.*

Basically, supplementing with Betaine may help boost power, strength, overall performance, and muscle growth![13,14]*

L-Tyrosine (2,000mg)

L-Taurine (1,000mg)

Choline Bitartrate (1,000mg)

Choline is an essential nutrient that plays a number of roles in the body as a methyl group donor as well as a necessary component for the synthesis of cell membranes. [15,16]*

The vital nutrient is also needed for the construction of an extremely important neurotransmitter called acetylcholine -- the “learning” neurotransmitter.* 

As the name implies, acetylcholine is heaving involved in learning, and it’s also involved in memory, cognition, and muscular contractions. *

To promote tighter focus and a more robust mind-muscle connections, Mega High Stim Preworkout includes a full 1 gram of choline bitartrate.*

Caffeine Anhydrous (250mg)

Caffeine is the preeminent pre workout stimulant, included to ignite the nervous system, spark motivation, and boost athletic performance.*

Caffeine works primarily by antagonizing adenosine receptors.*

Adenosine is a neurotransmitter that accumulates in extracellular space as ATP (adenosine triphosphate) breaks down. *

When enough adenosine accumulates, adenosine receptors are activated which inhibits the release of several key neurotransmitters, many of which play a role in keeping you alert, attentive, and cognitively “with it.”* 

More specifically, the neurotransmitters directly affected by adenosine receptor activation includes [21]:*

  • Acetylcholine (the “learning neurotransmitter”)
  • Dopamine (the “reward” molecule)
  • Noradrenaline
  • Serotonin (5-HT)
  • Glutamate (an excitatory neurotransmitter)

Therefore, if you don’t want to feel tired, or want to avoid the onset of fatigue it makes sense you would want to stop adenosine from exerting its effects in the body.* 

That’s the beauty of caffeine.*

It is structurally similar to adenosine and competitively inhibits the adenosine receptor, meaning adenosine can’t bind to its receptor.*

This is why when you ingest caffeine, you feel more upbeat, alert, and energetic.*

But caffeine’s benefits extend beyond increased feelings of energy and motivation.* 

Research has shown that caffeine supplementation can increase energy expenditure as well as strength, endurance, and anaerobic performance (i.e. resistance training). [17,18,19,20]*

CognatiQ® (100mg)

Theobromine (100mg)

Infinergy™ Dicaffeine Malate (68mg)

Mega High Stim Preworkout catapults you off the starting line with a robust 250mg of fast-acting caffeine anhydrous. Most pre workouts would stop there, but we wanted to deliver the best pre workout energy experience possible, and because of that, we’ve included an additional 68mg of Infinergy dicaffeine malate.* 

This slow-releasing form of caffeine provides a sustained release of energy that helps avoid any crash typically experienced with other high-stimulant pre workouts, and ensure you have ample energy to finish your workout and still get work done afterwards.*

Toothed Clubmoss Huperzine A 1% (50mcg)

Huperzine A is a powerful nootropic that complements choline-boosting properties of choline bitartrate.*

How do the two ingredients complement each other?

Choline bitartrate helps directly support acetylcholine production by increasing levels of choline in the body. Huperzine A indirectly enhances acetylcholine levels by inhibiting acetylcholinesterase -- the enzyme that breaks down acetylcholine.[39]* 

By stacking Huperzine A with a choline donor, Mega High Stim Preworkout helps promote greater acetylcholine levels via two different pathways, fostering more dialed-in focus and a stronger mind-muscle connection.*


*These statements have not been evaluated by the Food and Drug Administration.  This product is not intended to diagnose, treat, cure, or prevent any disease.



  1. George K. Grimble; Adverse Gastrointestinal Effects of Arginine and Related Amino Acids, The Journal of Nutrition, Volume 137, Issue 6, 1 June 2007, Pages 1693S–1701S,
  2. Bahri, S., Zerrouk, N., Aussel, C., Moinard, C., Crenn, P., Curis, E., … Sfar, S. (2013). Citrulline: from metabolism to therapeutic use. Nutrition (Burbank, Los Angeles County, Calif.), 29(3), 479–484.
  3. Curis E., et. al; “Citrulline and the gut;”; Current Opinion in Clinical Nutrition and Metabolic Care; September 2007
  4. Bailey SJ, Blackwell JR, Lord T, Vanhatalo A, Winyard PG, Jones AM. l-Citrulline supplementation improves O2 uptake kinetics and high-intensity exercise performance in humans. J Appl Physiol (1985). 2015 Aug 15;119(4):385-95
  5. Gonzales JU, Raymond A, Ashley J, Kim Y. Does L-citrulline supplementation improve exercise blood flow in older adults? Experimental physiology. 2017;102(12):1661-1671. doi:10.1113/EP086587.
  6. Suzuki T, Morita M, Kobayashi Y, Kamimura A. Oral L-citrulline supplementation enhances cycling time trial performance in healthy trained men: Double-blind randomized placebo-controlled 2-way crossover study. J Int Soc Sports Nutr. 2016;13(1):6. doi:10.1186/s12970-016-0117-z.
  7. Gonzales JU, Raymond A, Ashley J, Kim Y. Does l-citrulline supplementation improve exercise blood flow in older adults? Exp Physiol. September 2017. doi:10.1113/EP086587.
  8. Baguet, A et al.; Journal of Applied Physiology; “Important role of muscle carnosine in rowing performance;” July 2010;” 2005
  9. Roger C. Harris; et al.; “The effect of a supplement containing β-alanine on muscle carnosine synthesis, ventilatory threshold and exercise capacity in Korean cyclists, during 12 weeks combined endurance and weight training
  10. Hill, CA et al.; Amino Acids; “Influence of beta-alanine supplementation on skeletal muscle carnosine concentrations and high intensity cycling capacity ;” February 2007
  11. Kendrick IP, et al. The effects of 10 weeks of resistance training combined with beta-alanine supplementation on whole body strength, force production, muscular endurance and body composition. Amino Acids. (2008)
  12. Smith AE, Walter AA, Graef JL, et al. Effects of β-alanine supplementation and high-intensity interval training on endurance performance and body composition in men; a double-blind trial. Journal of the International Society of Sports Nutrition. 2009;6:5. doi:10.1186/1550-2783-6-5.
  13. Lee EC, Maresh CM, Kraemer WJ, et al. Ergogenic effects of betaine supplementation on strength and power performance. Journal of the International Society of Sports Nutrition. 2010;7:27. doi:10.1186/1550-2783-7-27.
  14. Trepanowski JF, Farney TM, McCarthy CG, Schilling BK, Craig SA, Bloomer RJ. The effects of chronic betaine supplementation on exercise performance, skeletal muscle oxygen saturation and associated biochemical parameters in resistance trained men. J Strength Cond Res. 2011;25. doi:10.1519/JSC.0b013e318217d48d.
  15. Wallace JMW, McCormack JM, McNulty H, et al. Choline supplementation and measures of choline and betaine status: a randomised, controlled trial in postmenopausal women. Br J Nutr. 2012;108(7):1264-1271. doi:10.1017/S000711451100674X.
  16. Cohen BM, Renshaw PF, Stoll AL, Wurtman RJ, Yurgelun-Todd D, Babb SM. Decreased brain choline uptake in older adults. An in vivo proton magnetic resonance spectroscopy study. JAMA. 1995;274(11):902-907.
  17. Mora-Rodríguez R, Pallarés JG, López-Samanes Á, Ortega JF, Fernández-Elías VE. Caffeine Ingestion Reverses the Circadian Rhythm Effects on Neuromuscular Performance in Highly Resistance-Trained Men. Bacurau RFP, ed. PLoS ONE. 2012;7(4):e33807. doi:10.1371/journal.pone.0033807.
  18. Astorino, T. A., Rohmann, R. L., & Firth, K. (2008). Effect of caffeine ingestion on one-repetition maximum muscular strength. European Journal of Applied Physiology, 102(2), 127–132.
  19. Beck, T. W., Housh, T. J., Schmidt, R. J., Johnson, G. O., Housh, D. J., Coburn, J. W., & Malek, M. H. (2006). The acute effects of a caffeine-containing supplement on strength, muscular endurance, and anaerobic capabilities. Journal of Strength and Conditioning Research, 20(3), 506–510.
  20. Ganio, M. S., Klau, J. F., Casa, D. J., Armstrong, L. E., & Maresh, C. M. (2009). Effect of caffeine on sport-specific endurance performance: a systematic review. Journal of Strength and Conditioning Research, 23(1), 315–324.
  21. Sperlágh B, Vizi ES. The role of extracellular adenosine in chemical neurotransmission in the hippocampus and Basal Ganglia: pharmacological and clinical aspects. Curr Top Med Chem. 2011;11(8):1034-46.
  22. Rohdewald  P A review of the French maritime pine bark extract (Pycnogenol), a herbal medication with a diverse clinical pharmacology.  Int J Clin Pharmacol Ther 2002;40 (4) 158- 168
  23. Liu  XWei  JTan  FZhou  SWürthwein  GRohdewald  P Pycnogenol, French maritime pine bark extract, improves endothelial function of hypertensive patients.  Life Sci 2004;74 (7) 855- 862
  24. Fitzpatrick  DFBing  BRohdewald  P Endothelium-dependent vascular effects of Pycnogenol.  J Cardiovasc Pharmacol 1998;32 (4) 509- 515
  25. Shand  BStrey  CScott  RMorrison  ZGieseg  S Pilot study on the clinical effects of dietary supplementation with Enzogenol, a flavonoid extract of pine bark and vitamin C.  Phytother Res 2003;17 (5) 490- 494
  26. Liu  XZhou  HJRohdewald  P French maritime pine bark extract Pycnogenol dose-dependently lowers glucose in type 2 diabetic patients.  Diabetes Care 2004;27 (3) 839
  27. Taylor L, Mumford P, Roberts M, et al. Safety of TeaCrine®®, a non-habituating, naturally-occurring purine alkaloid over eight weeks of continuous use. J Int Soc Sports Nutr. 2016;13(1):1-14. doi:10.1186/s12970-016-0113-3.
  28. He H, Ma D, Crone LB, et al. Assessment of the Drug-Drug Interaction Potential Between Theacrine and Caffeine  in Humans. J Caffeine Res. 2017;7(3):95-102. doi:10.1089/jcr.2017.0006.
  29. Wang Y, Yang X, Zheng X, Li J, Ye C, Song X. Theacrine, a purine alkaloid with anti-inflammatory and analgesic activities. Fitoterapia. 2010;81(6):627-631. doi:
  30. Kuhman DJ, Joyner KJ, Bloomer RJ. Cognitive Performance and Mood Following Ingestion of a Theacrine-Containing Dietary Supplement, Caffeine, or Placebo by Young Men and Women. Nutrients. 2015;7(11):9618-32. Published 2015 Nov 19. doi:10.3390/nu7115484
  31. Reyes T, Shu C, Argumedo R, Nemzer B, Pietrzkowski Z. The Effect of ElevATPTMon Whole Blood ATP Levels: A Single Dose, Cross over Clinical Study. Vol 1.; 2014.
  32. Joy J, Vogel R, Moon J, Falcone P, Mosman M, P. Kim M. Twelve Weeks Supplementation with an Extended-Release Caffeine and ATP-Enhancing Supplement May Improve Body Composition without Affecting Hematology in Resistance-Trained Men. Vol 13.; 2016. doi:10.1186/s12970-016-0136-9.
  33. Joy J, Falcone P, Vogel R, Mosman M, P Kim M, Moon J. Supplementation with a Proprietary Blend of Ancient Peat and Apple Extract May Improve Body Composition without Affecting Hematology in Resistance-Trained Men. Vol 40.; 2015. doi:10.1139/apnm-2015-0241.
  34. Joy JM et al., “Ancient peat and apple extracts supplementation may improve strength and power adaptations in resistance trained men,” BMC Complementary and Alternative Medicine, vol. 16, no. 1 (July 2016): 224;
  35. Reyes-Izquierdo, T., Nemzer, B., Argumedo, R., Cervantes, M., & Pietrzkowski, Z. (2016). The Effect of ElevATP on Exercise Output: A Single Dose, Blinded, Three-Way Cross-Over Study. Current Trends in Nutraceuticals
  36. Nyberg M, Mortensen SP, Thaning P, Saltin B, Hellsten Y. Interstitial and plasma adenosine stimulate nitric oxide and prostacyclin formation in human skeletal muscle. Hypertens (Dallas, Tex  1979). 2010;56(6):1102-1108. doi:10.1161/HYPERTENSIONAHA.110.161521.
  37. Sprague, R. S., Bowles, E. A., Achilleus, D. and Ellsworth, M. L. (2011), Erythrocytes as controllers of perfusion distribution in the microvasculature of skeletal muscle. Acta Physiologica, 202: 285-292. doi:10.1111/j.1748-1716.2010.02182.x
  38. Jäger R, Roberts MD, Lowery RP, et al. Oral adenosine-5’-triphosphate (ATP) administration increases blood flow following exercise in animals and humans. J Int Soc Sports Nutr. 2014;11(1):28. doi:10.1186/1550-2783-11-28
  39. 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
  40. 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
  41. 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

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

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Customer Reviews

Based on 63 reviews
Brent Stack
Lost in the mail

After my package going back and forth through the mail, I finally received my package, with nothing in it! I literally got an empty envelope. I’ve emailed several times, showing package stamped no contents and a video of it going out for delivery and back about 4-5 times. They said they’d look into it. A month later, still nothing. $50 for air

Milton Fuentes
Great Pre

Has a nice kick to it

Michael Meyers
Mega Pre Black

It's ok. I prefer Ape Sh*t more. I feel more of a pump from it. Sorry.

Jason M.
F-ing awesome!

I’m so glad I went with Mega pre black. I love the pumps in the gym and the focus it generates.

Crazy focused.

Ima beginner when it comes to supplements. Two scoops of this and I was another person. I’d recommend starting out with one at first getting a feel of it. Two scoops definitely on heavy days.
Taste wise I should’ve got another flavor cause I’m not too big on the sherbet flavor but thought I’d just try it.
Had me in the gym adding more weight than I usually do. I usually struggle squatting 205, this sh** had me squatting 250 feeling hella locked in and shocked. Was gonna shoot for more weight but kinda scared myself😂. 5’7 only 160....pretty slim guy.... Was unexpected and a shock to me. Not talking out my ass or sugar coating this but I’d highly recommend.