What is the difference between Fladrafinil and Flmodafinil?

Fladrafinil vs Flmodafinil - how do they compare?

So recently I came across two interesting Smart Drugs on Reddit searching for some information about Adrafinil and Modafinil.

I actually had no idea about them and what they do, so I figured, why not write an article about them in order to figure both of them out. Fladrafinil vs Flmodafinil - what's the difference? Let's find out.

Here are the topics I will be covering today:

  • What is Fladrafinil?
  • What is Flmodafinil?
  • How do they work and what's the difference?
  • What are the benefits and side effects?
  • What's the right dosage for you?
  • What are people on Reddit saying about both of them?

.... So without further ado, let's just jump straight into it!

What is Fladrafinil?

Fladrafinil is also known as CRL-40,941 or Fluorafinil. It is a eugeroic related to Adrafinil and Modafinil.

A eugeroic is a drug that promotes wakefulness and alertness which is why people often stumble upon Fladrafinil, like me, when researching Adrafinil and Modafinil.

From what I could find, Fladrafinil was first synthesized back in the '70s and was later patented in France in the late '80s.

People taking Fladrafinil report similar effects as Modafinil and Adrafinil although some argue that Fladrafinil is a more potent eugeroic compared to the two.

I couldn't really find any clinical study about Fladrafinil and the information about it is very limited as of right now. Most of the information we have available is anecdotes.

In summary;

Fladrafinil is more intense wakefulness and alertness promoting Smart Drug than Modafinil and Adrafinil with limited studies about it available (most information we have are anecdotes).

What is Flmodafinil?

Flmodafinil is found under 4 different names;

  • CRL-40,940
  • Flmodafinil
  • Bisfluoromodafinil
  • Lauflumide (NLS-4)

It is the bisfluoro analog of Modafinil. An analog just basically means that the compound has a similar chemical structure to Modafinil with a few differences.

Like Fladrafinil, Flmodafinil (crl 40,940) is also a potent eugeroic as well as a dopamine reuptake inhibitor.

Most people taking Flmodafinil report that it is more potent than Modafinil (up to 30% stronger and higher bioavailability) which is backed up by a few clinical studies.

Flmodafinil works by increasing the levels of histamine in the hypothalamus.

Histamine is a neurotransmitter that is associated with wakefulness and Flmodafinil increases its production.

Again, I couldn't find any good clinical study about Flmodafinil but there are quite a few studies about Modafinil so we can make some assumptions.

Here is what one study concluded:

"In summary, NLS-4 is a potent stimulant with different effects than its parent compound modafinil (Rambert et al., 1986) and most other stimulants in terms of potency and effects on sleep rebound and the sleep EEG."

You can find the study here.

It's worth noting that it was only recently patented (2013) and clinical trials have been underway since 2015. It is currently in Phase 1.

If you want to buy flmodafinil it's important to make sure that it is pure and not contaminated with any other drugs which can happen a lot for people who purchase flmodafinil.

That's why it's important to check your flmodafinil powder or capsules to see if it's pure or not.

Also, check the legality of flmodafinil. Is Flmodafinil legal in your country or not?

In summary;

Flmodafinil (crl 40,940) is a powerful eugeroic - wakefulness and alertness promoting Smart Drug. It is an analog to Modafinil which means that it is similar in structure. Flmodafinil is considered to be stronger than Modafinil with promising results in clinical trials. You can buy flmodafinil online at most vendors.

Flmodafinil vs Fladrafinil - what's the difference?

As I briefly mentioned in the beginning, the data available on both drugs is relatively limited.

That being said, we know that both Fladrafinil and Flmodafinil are powerful eugeroics that mimic the effects of Adrafinil and Modafinil.

Since they are both analogs to Modafinil and Adrafinil they work just the same in terms of wakefulness and alertness.

This means that they both have similar neuropsychopharmacological properties.

The only difference between Fladrafinil and Flmodafinil powder from the studies I could find are the side effects and potency.

Fladrafinil seems to have more severe side effects when compared to both Adrafinil and Flmodafinil which is why most people shy away from it.

Fladrafinil Benefits & Side Effects

When it comes to the potential benefits and side effects of using Fladrafinil, they are almost the same as what you'll experience taking Adrafinil alone.


That being said, Fladrafinil seems to have more severe side effects as I alluded to earlier.

Theoretically, the benefits you should experience on fladrafinil are:

  • Focus
  • Alertness
  • Creativity
  • Wakefulness

However, in most cases, people report that they experience nasty headaches, anxiety, and nervousness like this guy on Reddit.

The side effects experienced on Fladrafinil are the reason why most people chose Adrafinil instead.

Clinical Trials: Flmodafinil Dosage, Benefits & Side Effects

As briefly mentioned, clinical trials are currently underway to assess the safety and efficacy of Flmodafinil in various populations such as shift workers, patients with obstructive sleep apnea (OSA), and adults with ADHD.

When it comes to anecdotal evidence of Flmodafinil benefits (crl 40,940) people actually report that they experience better benefits than Modafinil.

The benefits you may experience taking Flmodafinil are:

  • Wakefulness (helps with sleeping disorders)
  • Alertness
  • Better focus
  • Creativity

Basically the same benefits as what you'd get taking Modafinil. Flmodafinil tends to be cheaper and is quicker to kick in.

Although some people say that Flmodafinil (crl 40,940) is one of those Smart Drugs that you either: "feel it working or not" (this guy on Reddit talks about it here).

In terms of Flmodafinil side effects there don't seem to be anything worth noting other than the common headache (usually a result of dehydration) and trouble sleeping if taken late in the day.

What's the best Fladrafinil and Flmodafinil Dosage?

When it comes to Nootropics, and Smart Drugs in general, dosages always depend on tolerance, weight, and personal goals.

Since Fladrafinil is more potent than Adrafinil, it is recommended to start out with a lower dose and then work your way up.

  • A low Fladrafinil dosage is: 20-50 mg
  • A high Fladrafinil dosage is: 60-100 mg

Fladrafinil comes in both powder form and capsules.

When it comes to Flmodafinil a smaller dose is also preferred because of the higher bioavailability.

People taking Modafinil will know that an effective dose is anywhere from 100 to 400 mg. With flmodafinil it is recommended to start out with 50 mg and then work your way up to assess the effects.

Flmodafinil also has a longer half-life which means that it will stay in your system longer. Some people report that they can feel the effects for up to 16 hours.

This is why it's generally recommended to take it early in the morning.

Here's a dosage reference range:

  • A low Flmodafinil dose is: 50-100 mg
  • A high Flmodafinil dose is: 150+ mg

It's also worth noting that Flmodafinil, in high doses, can cause euphoria, and some even report that they get Mania-like effects.

Flmodafinil Capsules and powder

Is Flmodafinil a wakefulness-promoting agent?

As briefly mentioned above, both Flmodafinil and Fladrafinil are wakefulness-promoting agents.

They achieve this by activating orexinergic neurons in the hypothalamus.

Orexin is a neuropeptide responsible for regulating arousal, wakefulness, and appetite.

When these neurons are activated, they release orexin which then binds to orexin receptors in the brain.

This leads to an increase in energy and vigilance, which is what makes these Nootropics so popular.

This is also why you should be careful when considering the optimal flmodafinil dosage.

Too much orexin can lead to feelings of anxiety and even mania.

Be sure to consult a professional if you are considering taking Flmodafinil.

Flmodafinil vs Modafinil - Which one is the best Smart Drug?

The two drugs are very similar, there are a few key differences.

Flmodafinil is more potent and has a quicker onset than Modafinil.

It is also thought to have a longer half-life as well. Some people see it as improved modafinil.

This means that it will stay in your system for longer and you may feel the effects for up to 16 hours.

Flmodafinil is also cheaper than Modafinil and has fewer side effects.

Here's a complete overview of these two drugs (Flmodafinil vs modafinil):

  • Flmodafinil is more potent than Modafinil
  • They act the same and therapeutic uses are the same
  • Both modafinil and flmodafinil act as wakefulness-promoting agents (promote wakefulness)
  • They help combat sleep deprivation as a result of sleep disorders
  • Flmodafinil is considered a research chemical
  • Both act as a central nervous system stimulant
  • Flmodafinil is currently undergoing clinical trials
  • You can buy flmodafinil online (as a research chemical)

Flmodafinil & Excessive Daytime Sleepiness

A high dose of flmodafinil is usually considered a great treatment for excessive daytime sleepiness.

When I say high dose I mean 100mg.

What do people on Reddit say about Fladrafinil vs Flmodafinil?


I thought it would be interesting to find, and combine, a couple of anecdotes from Reddit to see what people who are actually taking it are saying.

Here are some of the threads I could find.

I have linked to each one so you can go over to Reddit and read them for yourself.


The first thread I could find is from a user called; u/ThirdHuman.

He starts off the thread by simply asking: "Thoughts on Fladrafinil?"

A user called; rmcfar11 then replies that he LOVES Fladrafinil and of all the finil-logs he has tried, Fladrafinil is the best.

Rmcfar11 takes around 50 mg/day (and have done so for 6 months) and here is what he concludes:

"Soon after a dose, I would feel very aware of my surroundings, had good reaction time, and my brain just felt wide awake, but not uncomfortably so. The anti-aggressive effects that were noted in literature I think were valid."


The first thread about Flmodafinil I could find is from a user called; u/spellegrinoismyshit.

The entire thread is his own personal experience with Flmodafinil. He starts off by saying that he has taken a flmodafinil dosage of 250-300mg for the past week with no signs of a tolerance buildup.

Spellegrino, didn't experience any benefits using a low flmodafinil dose (50mg). Once he started taking 300mg is where he felt the full effects, or as he puts it:

"Once I started on 300mg, the next full week was great. Good things about it would be the feeling of being fully awake"

Interestingly enough he then goes on to talk about how his thinking is more logical when taking Flmodafinil.

He also says that his binge-eating has become way more controllable (he has to force himself to eat now, rather than force himself to stop).

Spellegrino also notes that there is no "High-chasing" as is the case with Modafinil. You either feel it or not.

He then finishes off by saying that he hasn't really experienced any negative side effects.

FAQ - About Flmodafinil & Fladrafinil

Q: Is Flmodafinil legal in the US?

A: Modafinil is a schedule IV psychoactive drug in the United States that can only be obtained with a prescription. The same goes for Flmodafinil.

Q: Is Flmodafinil water soluble?

A: Flmodafinil is not readily soluble in water or ethanol, and it is poorly soluble in both.

Q: Is Flmodafinil effective?

A: Yes, Flmodafinil can be effective when it comes to enhancing cognitive processes.

Q: How long does flmodafinil stay in your system?

A: The elimination half-life of modafinil is about 8 hours ­meaning that if you take 100mg of flmodafinil, 50mg will be eliminated from your system in 8 hours.

Q: What are the side effects of flmodafinil?

A: Some common side effects associated with flmodafinil include headaches, nausea, vomiting, and anxiety. Rarer side effects include Stevens-Johnson Syndrome and toxic epidermal necrolysis.

Q: How does flmodafinil compare to other drugs?

A: Flmodafinil is a potent CYP2C19 inhibitor, meaning that it can inhibit the metabolism of other drugs. It is also a weak CYP3A4 inhibitor and inducer, which can affect the metabolism of other drugs as well.

Q: Does Flmodafinil help with focus and concentration?

A: For some people, taking flmodafinil helps them to stay focused and concentrate on their work at hand. Other users report increased distractibility when they take the drug.

Q: Are there any potential interactions between flmodafinil and alcohol?

A: Flmodafinil can potentially interact with alcohol, but it is not well understood. You should avoid using the two together.

Q: Can I take Flmodafinil if I have high blood pressure?

A: Taking high dosages of flmodafinil can increase blood pressure, so you should speak to your doctor if you have high blood pressure before taking the drug.

Q: What is the difference between Fladrafinil and Flmodafinil?

A: The main difference between fladrafinil and flmodafinil is that fladrafinil is not as potent as flmodafinil. Additionally, fladrafinil is not as well-absorbed by the body as flmodafinil, so it needs to be taken in higher doses for it to be effective. Lastly, fladrafinil has a longer elimination half-life than flmodafinil.

Q: Does Flmodafinil work for everyone?

A: No, flmodafinil does not work for everyone. Some people report no effects from taking the drug, while others find that it helps to improve their cognitive function.

Q: What is the recommended dosage of Flmodafinil?

A: The recommended dosage of flmodafinil varies depending on whether it is used to treat narcolepsy or increase wakefulness. The usual dosage for the treatment of narcolepsy is 100mg, taken daily in the morning. For the purpose of maintaining wakefulness, 100-200mg can be taken once a day between 30 minutes and 1 hour before starting work.

Q: What should I do if I experience any side effects from taking Flmodafinil?

A: If you experience any side effects from taking flmodafinil, you should speak to your doctor. Some side effects may be mild and can be tolerated, but others may be more severe and require medical attention.

Q: Can Flmodafinil cause false-positive results on drug tests?

A: Yes, it is possible for flmodafinil to cause false-positive results on drug tests. This is particularly likely if you have a higher dose of the drug in your system.

Q: Can Flmodafinil cause Stevens-Johnson Syndrome?

A: Yes, there is a potential for flmodafinil to cause Stevens-Johnson Syndrome. This is a rare but serious skin reaction that can be life-threatening. If you experience any signs or symptoms of this reaction, you should stop taking flmodafinil and seek medical attention.