Hydrafinil | Review of Benefits, Side Effects, & More

Tomas Thorne

Last Updated: February 2, 2023

Hydrafinil Review

Curious about Hydrafinil?

You’ve come to just the right place. In this Hydrafinil review, we’ll offer an overview of this nootropic, from its purported benefits and side effects, to where to buy some online.

Hydrafinil is a “eugeroic” that has been shown to promote alertness and wakefulness. It’s cheaper to buy than Modafinil and anecdotal evidence suggests that it causes fewer side effects.

However, you’ll be hard-pressed to find any peer-reviewed scientific studies or published information about this new and exciting cognitive stimulant.

This raises some very important questions…

Is Hydrafinil safe for research subjects? Is it a powerful focus enhancer, surpassing even Modafinil and its cousins Armodafinil and Adrafinil in terms of effectiveness?

In this guide, we’ll address both of these questions and more, including:

  • What might be the best Hydrafinil dose to administer?
  • What side effects can Hydrafinil cause?
  • Where can researchers buy Hydrafinil online?

So, if you’re curious about Hydrafinil and what it can do for you, just keep reading!

Click here to order Hydrafinil from our top vendor!

Disclaimer: The contents of Modafinil.com are for informational and educational purposes only. We do not provide legal advice. Likewise, we do not provide medical advice, diagnosis, or treatment. Please consult your physician prior to consuming Modafinil or related nootropics. Your access to Modafinil.com is subject to our full Disclaimer and Terms of Use.

Hydrafinil Review | Overview

Hydrafinil (a.k.a. 9-fluorenol, 9-Hydroxyfluorene, fluorenol) is a Modafinil analog that acts as a weak dopamine reuptake inhibitor [1].

While Modafinil and Hydrafinil may not look as if they share many structural similarities, they are very closely related to each other. As noted by Dunn et al. in their work towards finding new Modafinil derivatives, studies have indicated that Hydrafinil is 39 percent more effective than Modafinil at promoting wakefulness in rats [2].

While peer-reviewed studies into Hydrafinil as a nootropic are virtually nonexistent, researchers have indicated that it has the following properties:

  • It has shown similar eugeroic (i.e., wakefulness-enhancing) activity to Modafinil;
  • It affects the same neurotransmitters as Modafinil (i.e., glutamate, dopamine and histamine);
  • It’s potentially more efficacious than Modafinil with respect to mood, memory, alertness and overall productivity.

Unlike Modafinil, Hydrafinil is NOT approved by the FDA, nor is it used to treat any of the sleep-related disorders for which Modafinil is typically prescribed, including obstructive sleep apnea, narcolepsy and shift work sleep disorder [3].

Hydrafinil’s status as an unregulated research drug has aroused researchers’ interest in Hydrafinil as a potentially safer and more effective Modafinil alternative.

Review Hydrafinil

Hydrafinil Benefits

Now that you have a basic idea of what Hydrafinil is, let’s turn our attention to some of its purported cognitive benefits.

Since there’s a lack of studies focusing on Hydrafinil directly, we’re left with mostly anecdotal reports and studies on similar compounds such as Modafinil and Adrafinil.

Hydrafinil Potentially Boosts Alertness Without the “Jitters”

The aforementioned study by Dunn et al., designed to determine the next generation of wake-promoting supplements, appeared to attribute Hydrafinil’s activity to increased alertness in rats [2]:

“As shown in Table 1, subsequent screening in wake-promoting assay in rats, compound 3 (Compound 3 is hydrafinil, 100 mg/kg ip) was found to be active. Thus, it is likely that the wake-promoting activity of compound 15 in rats might have arisen from the activity of compound 3.”

Despite the scarcity of peer-reviewed research studies on Hydrafinil in humans, there are many promising informal reports published by human research subjects on the new compound. Here’s one account [4]:

“T:+1h – Effects are in full swing. This dosage is reminiscent of the higher doses of Adrafinil that I have tried however it feels cleaner subjectively. The wakefulness promotion given by Hydrafinil can only be described as clean stimulation (not in the same vein as standard stimulants).” [sic]

Put another way, Hydrafinil, like Modafinil, is not a stimulant in the traditional sense. Hydrafinil subjects report gaining more focus and alertness without feeling “wired” or jittery, which can happen with other cognitive enhancers like Adderall and caffeine.

Hydrafinil Potentially Reduces Daytime Fatigue

While Hydrafinil is not FDA-approved for any use, much less treating fatigue, one anecdotal report suggests that Hydrafinil helps relieve fatigue within 30 minutes in subjects with busy lifestyles [4]:

“… T:+30m – Started to feel the effects of the initial dose beyond what I imagine to be placebo. I’m generally slightly fatigued due to sleep deprivation for my working schedule this fatigue was removed almost completely.” [sic]

Daytime fatigue is a common problem that can make even the smallest decision seem like a chore. Hydrafinil reportedly eliminates that feeling, making decision-making easier throughout the day.

Hydrafinil Potentially Promotes Wakefulness Without Disrupting the Subject’s Sleep Schedule

Although pharmacokinetic data for Hydrafinil remains limited, the same anecdotal testimonial suggests that the research nootropic’s wakefulness-enhancing effects do not come at the cost of interfering with the subject’s sleep schedule [4]:

“T+4.2h – Dosing loses effectiveness and a return to baseline is present. No sort of crash to write home about however just a return to baseline wakefulness..” [sic]

This may be explained by Hydrafinil’s more powerful, yet shorter-lasting duration. Subjects report that Hydrafinil causes a bigger boost in cognition than Modafinil, yet that it lasts for just 4-6 hours, compared with 12+ for Modafinil. Hydrafinil’s shorter half-life means that it’s potentially far less likely to interfere with a human subject’s sleep schedule.

Hydrafinil Can Potentially Be Used For Polyphasic Sleep Cycles

Research subject anecdotes on Reddit promote Hydrafinil as a way to enter polyphasic sleep — the practice of sleeping for multiple periods throughout a full day. Some biohackers use the polyphasic sleep pattern to complete more tasks. Hydrafinil has given at least one subject the boost in wakefulness that they needed to adjust to this way of resting [5]:

“A person stayed up for 40 hours on hydrafinil by taking it every four hours. On the 35th hour, the person was still functioning normally and the Hydrafinil was in them. On the 36th hour, the hydrafinil wore off and the person felt extremely sleepy and tired and started to hallucinate due to the extreme sleep deprivation. Then the person took hydrafinil and functioned well the final four hours. The person even helped someone with homework and played video games like if they were rested. The person crashed at the 40th hour after the hydrafinil wore off and it was off to snoozeville for many hours.” [sic]

While the polyphasic sleep pattern may not be for everyone, this may signal yet another potential research application of Hydrafinil.

Hydrafinil Is Potentially Even Less Addictive and More Effective than Modafinil at Promoting Alertness

Like Modafinil, Hydrafinil is not a stimulant in the traditional sense. It’s a weak Dopamine Transporter (DAT) agonist, meaning that it’s able to increase alertness with minimal risk for addiction [6]:

“Fluorenol belongs to a class of drugs known as Eugeroics. These are stimulants that produce long-lasting mental arousal leading to wakefulness. The idea behind the production of these drugs is to enhance alertness without necessarily eliciting the peripheral body effects or better yet the abuse/tolerance/ addiction of the customary stimulants.

And Fluorenol is no different. Hydrafinil’s stimulation of dopamine pathways is far less substantial than modafinil’s which means that it is less likely to be addictive.”

Overall, Hydrafinil appears to be worthy of further research as an alternative to Adrafinil and Modafinil. This research compound has the potential to create a stronger cognitive boost than Modafinil at a lower dose, without some of the side effects associated with the latter two.

Hydrafinil Dosing, Side Effects and Safety

Given the lack of scientific research on Hydrafinil to date, you might be curious about its side effects or whether it’s safe to use for enhanced cognition.

NOTE: We are not aware of any toxicology studies, human studies or clinical reviews conducted on Hydrafinil to date. This means that researchers and their subjects are fully responsible for any effects that may arise from the responsible use of Hydrafinil.

From the testimonials we were able to gather, it seems that most subjects do not report any side effects when dosing Hydrafinil in the range of 20 mg to 250 mg per day. Potential health effects reported by Acros Organics, a chemical supplier of Hydrafinil under the common name 9-hydroxyfluorene, include [7]:

  • Eye irritation,
  • Skin irritation,
  • Nausea,
  • Diarrhea, and
  • Vomiting

Importantly, Hydrafinil’s Material Safety Data Sheets also state that the toxicology of this compound has not been fully investigated. Hydrafinil is not intended for human consumption, and there is no peer-reviewed scientific data to support a safe dosing range. Anecdotally, the most common daily dose of Hydrafinil appears to be 25-50 mg.

Hydrafinil Legality

Is Hydrafinil legal for you to buy and use? To make a long story short: It certainly does not have the same legal status as Modafinil.

In the United States, Modafinil is a Schedule IV prescription drug. That means you need a prescription to buy Modafinil from a pharmacy, and you are not allowed to share it or sell it to anybody.

As we mentioned earlier, Hydrafinil is an analog of Modafinil, so it’s not subject to the same restrictions. However, for those of you wondering if the well-known Federal Analogue Act (21 U.S.C. § 813) applies to Hydrafinil … it does not [8]:

“…[the act allows] any chemical “substantially similar” to a controlled substance listed in Schedule I or II to be treated as if it were listed in Schedule I, but only if intended for human consumption. (emphasis ours)

In other words…

Hydrafinil is an uncontrolled and unregulated research chemical that is not approved by the FDA for human use.

For this reason, you might see online vendors advertise Hydrafinil with a disclaimer to the following effect:

“This material is sold for research purposes only. It is not meant for human consumption, medical uses, household uses, or veterinary uses.”

Based on our personal experience and having compiled data from hundreds of Hydrafinil research subjects, here’s a brief cheat-sheet that tells you what all of the above means:

  • Hydrafinil, like Modafinil, will not show up on a drug test unless the examiner specifically screens for it [9].
  • Researchers can buy Hydrafinil online in restricted quantities without a prescription, similarly to how one could buy Modafinil online as a nootropic.
  • It’s 100% illegal for you to sell Hydrafinil to other people due to its status as a research chemical [10].

In summary, researchers are fully responsible for the proper use of Hydrafinil and any legal consequences that may arise from its purchase, possession and/or use.

Review Hydrafinil

Hydrafinil Pharmacology

Researchers have speculated that Hydrafinil’s primary mechanism of action is actually much different from Modafinil, Adrafinil and related analogs [11]:

“Dunn [8,9] reported that fluorenol which is the 9-hydroxyfluorene derivative formed from 9-Fluorenyl-S(=O)-CH2-C(=O)-(4N-piperazine-1N)-C(=O)-CH3 itself shows a stronger eugeroic effect but a 59% weaker DAT binding ability than modafinil. This result is unusual since fluorenol is vastly structurally different from modafinil indicating a quite different mechanism to that of modafinil.

Since the fluorene moiety can easily accommodate electron attachment, an investigation of electron attachment to fluorenol showed no evidence of bond elongation of the fluorene C9—OH bond ruling out the formation of a fluorene radical anion species similar to that shown by 9-fluorenyl-S(=O)-CH2-C(=O)-(4N-piperazine-1N)- C(=O)-CH3. However, an examination of electron attachment to the protonated fluorenol species 9-fluoreneOH2 + did show fluorene—OH2 + bond elongation, indicating a dissociative electron attachment reaction.” [sic]

Hydrafinil’s primary action doesn’t come from binding to the DAT and inhibiting dopamine uptake, which is why it’s believed to be less addictive than other DAT agonists.

The dissociative electron attachment reaction is a way to absorb free radicals. Free radical accumulation in the brain during the day is thought to be one of the many drivers of sleep [12]:

“Examination of modafinil and modafinil-like analogues which have been shown in the literature to exhibit wake-promoting and cognitive psychobiological properties are shown in this study to produce free radicals when subject to electron attachment. Such observations are consistent with a free radical oxidative stress eugeroic and cognitive altering mechanism for modafinil and related analogues.”

In other words, the metabolism of Modafinil and its analogues shows that in addition to DAT binding, the presence of free radicals in the brain drives sleep and removal of these free radicals may reverse this action.

“A meta-analysis of published studies on sleep deprivation and oxidative stress in the brain was used to test the hypothesis that sleep is a dynamic-resting state with antioxidative properties. Wakefulness is thought to involve high neuronal metabolism and neuronal electrical potentials, and requires high oxygen levels, and therefore oxidants.

Sleep is a state with an increased antioxidant activity that promotes a brain protection against free radicals by lowering oxidant production. ROS (Reactive Oxygen Species) and other oxidative stress markers can accumulate in the brain during wakefulness, and so behave as sleep promoters.”

This data, along with the observation of a dissociative bond mechanism in Hydrafinil, suggests that the eugeroic effect of Hydrafinil comes from its ability to absorb free radicals in the brain. This action is important since Hydrafinil is reported as a more potent eugeroic without the side effects of many other eugeroics available as prescription drugs or research chemicals.

Applying this data towards practical use, many subjects claim Hydrafinil takes 30-60 minutes before its effects kick in and lasts a total of 6-8 hours. For this reason, Hydrafinil likely has a shorter half-life compared to the Modafinil half-life of 12-15 hours.

Where To Buy Hydrafinil Online | 2022

So where can you buy Hydrafinil online without having to worry about product quality or shipping problems?

After extensively reviewing the few vendors who have Hydrafinil in stock, only one candidate met our strict requirements…

Science.bio is indisputably our preferred place to buy high-quality Hydrafinil online.

Despite being a relatively new company, Science.bio (formerly IRC.bio) has managed to establish itself as a highly reliable supplier of premium-quality research chemicals such as Hydrafinil and many others.

Here’s what you can expect when you order Hydrafinil from Science.bio.

Excellent Customer Service

Their communication with their customers is both timely and professional. Having submitted several inquiries ourselves, we were impressed at how quick and helpful their responses were.

This is directly reflected on their TrustPilot page, where they have a 4.5/5 rating across 25 reviews at the time of writing. The review below is a good summary of what you can expect from this vendor [13]:

“Highly recommended for reliable research products and exceptionally helpful & prompt customer service… I have been satisfied with multiple orders each month since.

Consistent quality with a wide variety of safe and secure payment methods to work with. Lots of special deals and coupons for all types of customers may be available throughout the year as well.”

Full Transparency About Product Quality

According to their official website, every product offered by Science.bio is “rigorously verified by PhDs in analytical and organic chemistry, including NMR, FTIR, Polarimetry, HPLC and LC-MS analysis.”

Every nootropic they ship comes with a complete data sheet, along with full audits of their production batches and product potency assessed through an independent 3rd-party Certificate of Analysis (CoA).

Considering Hydrafinil’s status as a research chemical, this information is mandatory for consumers.

FAST Shipping Times

All orders on Science.bio are shipped within 24 hours and a tracking number is immediately provided.

NOTE: Realistically, you should expect a timeframe of 1-3 days due to the current situation involving the COVID-19 pandemic.

We highly recommend stocking up on Hydrafinil and other products, as FREE first-class international shipping is offered to customers who make an order of over $300.

Your order will come professionally packaged, so you’ll never have to worry about the integrity of your research product.

And in the event that you don’t receive your product, or if the product arrives defective, Science.bio provides a 30-day 100% money-back guarantee.

Numerous Payment Methods

One of the major problems with online vendors is that there are very limited options for completing payment.

Fortunately, Science.bio accepts several options to accommodate their customers and their needs:

  • Credit card (Visa, MasterCard);
  • eCheck;
  • Bank wires;
  • Bank transfers; and
  • Bitcoin (save 5% off your total order price)

Based on our discussions with research subjects, this list covers 99% of the most common forms of payment.

All in all, Science.bio is the #1 Hydrafinil vendor and we highly recommend them!

Review Hydrafinil

Review of Hydrafinil | Verdict

So what can be concluded from this comprehensive Hydrafinil review?

Despite it being a relatively new research chemical, there are already a significant number of researchers and subjects claiming Hydrafinil to be an effective nootropic — comparable in some ways to Modafinil.

Here’s what we know so far:

Hydrafinil promises powerful cognition-enhancing effects and is potentially a must-have nootropic for short bouts of insane productivity and razor-sharp focus. It’s safe to take, easy to obtain, cheap to purchase and has few known side effects.

Research into Hydrafinil has indicated that it may be effective at boosting cognition while being less likely to interfere with the subject’s sleep schedule.

But not everyone will agree with the statements made above, and some subjects may not get the desired or expected outcome when taking Hydrafinil. Its potency, therefore, is entirely individual to the subject and their unique biochemical makeup.

Happy researching!

Click here to order Hydrafinil from our top vendor!


  1. Caymanchem.com. 2021. [online] Available at: <https://www.caymanchem.com/product/19799/fluorenol> [Accessed 26 February 2021].
  2. Dunn, D., Hostetler, G., Iqbal, M., Marcy, V. R., Lin, Y. G., Jones, B., Aimone, L. D., Gruner, J., Ator, M. A., Bacon, E. R., & Chatterjee, S. (2012). Wake promoting agents: search for next generation modafinil, lessons learned: part III. Bioorganic & medicinal chemistry letters, 22(11), 3751–3753. https://doi.org/10.1016/j.bmcl.2012.04.031
  3. Ba, & Social Distancing, Q. (2021). Modafinil Oral: Uses, Side Effects, Interactions, Pictures, Warnings & Dosing – WebMD. Webmd.com. Retrieved 26 February 2021, from https://www.webmd.com/drugs/2/drug-16962/modafinil-oral/details.
  4. (2021). Retrieved 26 February 2021, from https://www.reddit.com/r/Nootropics/comments/2ev8c4/hydrafinil_report/
  5. (2021). Retrieved 26 February 2021, from https://www.reddit.com/r/afinil/comments/359jmp/longterm_sleep_deprivation_and_polyphasic_sleep/
  6. Professional to supply Hydrafinil (fluorenol, 9-fluorenol) – Nutra Green. (2021). Retrieved 26 February 2021, from https://www.nutragreenbio.com/product/hydrafinil-fluorenol-9-fluorenol
  7. (2021). Retrieved 26 February 2021, from https://fscimage.fishersci.com/msds/26397.htm
  8. Federal Analogue Act. (2021). Retrieved 26 February 2021, from https://en.wikipedia.org/wiki/Federal_Analogue_Act
  9. (2021). Retrieved 26 February 2021, from https://www.reddit.com/r/afinil/comments/2wa5ci/does_adrafinil_or_hydrafinil_show_up_on_a_drug/%5d
  10. Labeled “Research” Chemicals, Doping Drugs Sold Openly on Amazon.com | News | Holland & Knight. Hklaw.com. (2021). Retrieved 26 February 2021, from https://www.hklaw.com/en/news/intheheadlines/2020/09/labeled-research-chemicals-doping-drugs-sold-openly-on-amazon.
  11. (2021). Retrieved 26 February 2021, from https://hal.archives-ouvertes.fr/hal-01693225v2/document
  12. (2021). Retrieved 26 February 2021, from https://hal.archives-ouvertes.fr/hal-01933737/document
  13. Science.bio is rated “Excellent” with 4.4 / 5 on Trustpilot. (2021). Retrieved 26 February 2021, from https://ca.trustpilot.com/review/science.bio

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