IDRA-21 Nootropic: Benefits, Review and Dosage


IDRA-21 Nootropic: Benefits, Review and Dosage

Modern Nootropics

If you REALLY want a nootropic experience like the ‘Limitless’ pill (taken from the film and book), we urge you to dig a little deeper into the world of biohacking and what direction current research is going in.

Nootropic and gaming supplement categories have boomed in the last year. Thanks to lockdowns, less people are working out, and more are spending their entire day in the same room, either working at their laptop or playing video games! It’s no surprise that people are having less trouble keeping focussed on the task at hand than ever. With little stimulation and glued to a screen all day, many people are feeling more mentally fatigued than ever despite doing less than they ever have!

The issue with lots of these ‘nootropic’ formulas on the market, however, is that they’re little more than a pre-workout. The fancy tubs and tasty flavours might catch your eye, but often all you’re really getting are pretty basic ingredients like caffeine, ALCAR, l-tyrosine…

Limitless Nootropics, who took their brand name inspiration from the film, are a brand doing just that and bringing advanced, ground-breaking nootropics to a mainstream audience. We know that many of these products will be things you’ve never seen before, which is why we’re here to give them a proper introduction. Starting with IDRA-21. Is THIS the real Limitless pill?

What is IDRA-21 and how does it work?

IDRA-21 is a nootropic compound derived from the benzothiadiazine chemical structure. If you are looking for a ‘comparable’ substance, Aniracetam is the example often given, although IDRA is up to 30x more potent (which in theory would make it 15x stronger than Noopept).

From here… it all gets a bit sciencey. IDRA-21 works by positive allosteric modulation of the glutamate AMPA receptors in the brain. Studies suggest that the compound can facilitate excitatory neurotransmission via GluR 1/2 receptors.

This mechanism of action places it in the drug class known as ‘ampakines’. Other nootropics drugs in this class include aniracetam, sunifiram and oxiracetam.

Benefits of IDRA-21

  • Improves cognition (learning and memory)
  • Increased mental focus
  • An increase in sensory perception
  • Potential application in aging related cognitive/memory disorders

The primary benefit of taking IDRA-21 capsules is a dramatic improvement in learning and memory. So much so, it may reverse damage in elderly subjects. IDRA strengthens synapses within the brain which leads to long term improved cognition. After a single dose of IDRA, benefits can be experienced for up to 3 days!

IDRA-21 Risks and Side Effects

Side effects from IDRA-21 supplementation are rare when used at an appropriate dose, which is one reason why one might use it over another nootropic. Side effects that have been reported include:

  • Dizziness
  • Anxiety
  • Headaches

You would in practice get worse potential side effects from drinking too much coffee or energy drinks so do not be unduly alarmed. In the rare event that these occur, it is thought to be due to an increase in glutamate neurotransmission. Please follow our manufacturer dosing instructions and be sure that the benefits of IDRA-21 are appropriate for you before starting use.

IDRA-21 is not advised for anyone who have suffered from a condition associated with excessive activation of AMPA receptors, such as stroke or seizure or otherwise suffers from any medical condition.

IDRA-21 User Review

It’s all well and good us talking about what IDRA ‘might/potentially/maybe/in theory’ does. But what would a guide be without hearing from REAL people who have tried it?

I’m a massive fan of nootropics myself. Being someone who doesn’t always get on with large doses of stimulants in one go (elevated heart rate triggers feelings of anxiety which actually detract from my ability to focus and work whether in the gym or the office), I would rather use smaller doses, complimented by nootropics.

Previous nootropic use includes some of your more ‘mainstream’ ingredients like huperzine and alpha GPC, to more ‘hardcore’ ones like modafinil and racetams. I was keen to find out where on the spectrum IDRA sat!

Now a few weeks into using IDRA daily, I can safely say I’m very satisfied with the effects. Limitless Nootropics do suggest adding a second dose after your first week of use, but I’ve been getting on just great with a single capsule an hour or so before I sit down to start work in the morning.

The effects are subtle, so don’t expect to feel it ‘kicking in’ (I crack open a can of 3D to sip over my first hour of work for that!). The incredibly long half-life (48 hours) also means that the effects are sustained when taken daily, with no feeling of coming down.

I’m someone who often gets overwhelmed when faced with a long ‘to do’ list and can find myself jumping from task to task not really completing anything efficiently. On IDRA, I’m able to apply myself fully to the most urgent task and box it off without losing interest or focus before moving onto the next.

IDRA-21 Dose and Stacking Guide

If using Limitless Nootropics IDRA-21, the recommended dose is 1 10mg capsule taken in a morning. After a week or so, you may wish to take a second capsule around midday.

Thanks to the long half-life of IDRA, some users report great results even using every other day! As with any supplement, start at a low dose and assess your individual response and tolerance over time, then you may adjust as needed so long as you are not exceeding 2 caps daily.

There is little known about the effects of stacking IDRA-21 with other nootropics currently, so we would advise caution when doing so. IDRA is potent enough to take as a standalone, but for nootropic buffs who have a good understanding of the MoA, they may want to experiment with using other complimentary ingredients as I have in my own review!


If it’s a REAL nootropic you’re after IDRA-21 is one that we would certainly recommend. IDRA works in the background pretty mildly, so shouldn’t scare off beginners, but is powerful enough to appeal to more experienced users who might’ve used things like racetams or noopept previously.

IDRA is long acting and doesn’t have a strong stim effect (the feeling is more of a pleasant wakefulness and alertness without jitters) so we wouldn’t advise it for a one-off cram study session. IDRA is best used daily for as long as results are desired, for professionals with mentally demanding jobs or students with long days of lectures.

If you do try IDRA, we’d love to hear your thoughts and experiences!

Further Reading

Buccafusco, J., Weiser, T., Winter, K., Klinder, K. and Terry, A., 2004. The effects of IDRA 21, a positive modulator of the AMPA receptor, on delayed matching performance by young and aged rhesus monkeys. Neuropharmacology, 46(1), pp.10-22.

Impagnatiello, F., Oberto, A., Longone, P., Costa, E. and Guidotti, A., 1997. 7-Chloro-3-methyl-3,4-dihydro-2H-1,2,4-benzothiadiazine S,S-dioxide: A partial modulator of AMPA receptor desensitization devoid of neurotoxicity. Proceedings of the National Academy of Sciences, 94(13), pp.7053-7058.

Yamada, K., Covey, D., Hsu, C., Hu, R., Hu, Y. and He, Y., 1998. The diazoxide derivative IDRA 21 enhances ischemic hippocampal neuron injury. Annals of Neurology, 43(5), pp.664-669.

About the Author


Savannah is part of the team here at Predator. Her qualifications include a degree in Sport and Exercise Nutrition alongside a background working in the supplement industry. She has also been actively competing in bodybuilding competitions since 2016. 

Social: @SavannahWesterby