Nootropics Safety & Side Effects

David Tomen
David Tomen
11 minute read

We use nootropics to enhance cognitive function. Because we want to perform better, improve our productivity and live our lives to our full potential.

But is there a cost to boosting cognitive function with nootropics?

It crosses the mind of nearly every neurohacker at one time or another. Is my nootropic stack safe? Is the nootropic I’m about to try going to do anything other than help?

In this post, we’re going to look past the hype. And take a critical look at nootropic safety and potential side effects.

Nootropic Track Record

First, let’s begin by defining what we mean by a “nootropic”. At Nootropics Expert® we start with the original definition and intent stated by Dr. Corneliu Giurgea, the man who designed Piracetam.

Dr. Giurgea stated that a nootropic must be non-toxic even with long-term use. It should be able protect the brain and even repair damage caused by pharmaceuticals and other toxins.

With this view of nootropics as brain enhancement supplements, we choose to exclude “smart drugs” from this category of neuro-enhancers. Including popular drugs like Adderall and Modafinil.

Nootropics are generally made from plants. The supplement is often taken from plant ingredients or extracts.

Many of these plant-based nootropics have been safely used for thousands of years. Bacopa Monnieri (Brahmi) which is used in my favorite pre-made stack Mind Lab Pro® for example, was mentioned in the ancient Ayurvedic texts. It was recommended to devotees to help memorize long passages of text.

Even the racetam family of nootropics are derived from biochemicals naturally produced in your body. For example, Piracetam is a cyclic derivative of GABA which is naturally produced throughout your body, including your brain.

Contrary to claims made by the pharmaceutical and some mainstream medical professionals, most nootropics have undergone extensive research. Even for long-term use by animals and humans.


Nootropic Safety

Part of the problem with Western medical journals is a lot of nootropic compound research has been done in countries other than the United States. Often in languages other than English. And are not included in databases like PubMed or Medline.

However, for us to claim there are no dangers in using nootropics would be unprofessional. And a disservice to you.

Each nootropic compound or substance has a different mechanism of action in the brain, and in your body.

Factors to consider by every neurohacker include dosage, your age, drug interaction or complications, duration and frequency of use, and affects in your brain on neurotransmitters, neurons and other cognitive functions.

One term you’ll come across frequently in nootropic circles and communities is YMMV. Which stands for “Your Mileage May Vary”. Each of us has unique bio-chemistry and we’re affected by our environment, the foods we eat, water we drink, air we breathe and even genetics inherited from our family.

Some neurohackers can use a nootropic for years with no problems. And stop usage with no effect on cognitive function. While others can use a supplement for years. And when discontinuing usage, experience significant cognitive impairment.

At Nootropics Expert, we do our best to provide the clinical research backing up each nootropic. We include dosage recommendations, side effects, and potential drug interactions for each nootropic.

Potential Nootropic Side Effects

We have common issues that can be applied to most of the nootropics we explore on Nootropics Expert. Many neurohackers will not experience side effects for most of the nootropic compounds we cover. But you could have issues.

It’s your responsibility as a neurohacker to thoroughly research each substance you’re considering adding to your nootropic stack. We are not medical professionals. And make no claims and cannot give advice that you should be getting from a medical professional you have a working relationship with.

Here is a list of potential side effects to help you evaluate each nootropic.

Brain ChemistryNootropics and brain chemistry

Each nootropic alters how your brain functions. The mechanism of action could include cerebral circulation, neurotransmitters, neuroreceptors, or hormone levels.

Some nootropics affect the most basic and critical functions of a brain cell including the cell membrane, mitochondria and even DNA. Others influence chemical movement into and out of brain cells. Or can act as an antioxidant and free radical scavenger.

This constant alteration in brain chemistry can expand or shrink certain areas of your brain. Altering how your brain works while you’re using the nootropic. Even after you discontinue use.


Many of the nootropics we use for optimizing cognition can interact with prescription drugs. And the reason why we often include warnings in the “Side Effects” section of each nootropic article on Nootropics Expert.

Some adverse reactions between a nootropic and a pharmaceutical can be deadly. So please carefully read the cautions and warnings we provide. And use other resources you can find online which provide extensive lists of contraindications.

We always suggest working with a medical professional like your doctor if you’re combining nootropics with prescription drugs. But most doctors know less than you about nootropics.

Do your research and listen to your body and brain. And always assume you may have a problem when combining prescription or OTC drugs with nootropics.

Cumulative Effects

Some nootropics can have a cumulative effect in your brain. Constant use of something like Huperzine-A for example can be a problem. Huperzine-A has a long half-life, and doesn’t leave your body as quickly as most other nootropics.Nootropics stacking

Huperzine-A can also be toxic if used in larger than recommended doses. Hup-A is a potent acetylcholinesterase (AChE) inhibitor. Which means Hup-A prevents the breakdown of acetylcholine (ACh). If you already have high levels of ACh you’re setting yourself up for a problem with excess ACh in your brain.

Huperzine-A is just one example of a nootropic that when used in too high a dose, or for continuous extended periods, can cause big problems.

Other nootropics act as stimulants that can take a toll on your neurons if used for extended periods. Others alter your circadian rhythm which can affect sleep and energy levels.

The strongest recommendation we can offer is to carefully read each nootropic article on Nootropics Expert. Take note of dosage recommendations, timing, and side effects.

And if you experience ANY problems, stop using that nootropic.


Some neurohackers report that extended nootropic usage for cognitive enhancement leaves them dependent on that nootropic.

When they stop using the nootropic, their cognitive function declines. Not only to baseline levels like when they started. But has a negative effect on cognition worse than what they tried to correct.

You know your body chemistry better than anyone else on earth. Listen to your body and brain. If you experience negative effects when stopping use of a nootropic, carefully assess your options.

You may want to completely avoid that nootropic. And find another nootropic that can help correct the problems caused by long-term usage of the original substance.

Most neurohackers will not experience this type of dependence using the same nootropic. Get to know your body and brain and listen.

Experimentation, knowledge and wisdom are critical when it comes to hacking your brain.

Lack of Regulation

Know who your supplier is for the nootropics you use in your stack. Do your best to get an assay of the compound you’re using verifying its purity and source.

Nootropic supplements are not regulated like pharmaceuticals. This is not as scary as it sounds because there is far more documented evidence of problems with prescription drugs than there are for nootropics and dietary supplements.

No one that we know of has overdosed and died because of nootropic usage. That’s not to say no one has ended up in the ER, or with serious health issues because of a nootropic. But the bottom-line is that nootropics are some of the safest and most vetted supplements on the market today.

Read the user reviews of each nootropic at the supplier you are considering using. Get to know your supplier and do your best to verify the quality of their product.

And research the heck out of each nootropic you’re using or plan to use. Nootropics Expert has dozens of clinical studies and user information for each nootropic we write about. Most we’ve tried or use daily ourselves.

Lack of regulation means the responsibility is entirely yours to use nootropics responsibly and safely.



We have plenty of evidence, scientific and user feedback on the problems with many pharmaceutical drugs.

Researchers discovered that benzodiazepines can cause dementia after following up with patients for 15 years.[i]

Anti-psychotics used in the treatment of schizophrenia have been found to cause brain shrinkage over time.[ii] Tricyclic antidepressants and antihistamines have been found to cause dementia and contribute to Alzheimer’s Disease.[iii]

My point in bringing up these findings with prescription pharmaceuticals used to treat everything from Alzheimer’s to a stuffed-up sinus to insomnia is that they affect neurotransmitters in your brain.

Nootropics often target neurotransmitters in your brain as well. Altering neurotransmitters and neurotransmission is serious business. And can have equally serious consequences if we’re not careful.

For optimal cognition and brain health, your brain maintains a delicate balance of all neurotransmitters. Each works in synergy with another and is often dependent on optimal neurotransmitter levels, good cerebral blood flow, and many other factors.

Boosting a neurotransmitter like dopamine too much and for extended periods can damage or kill neurons or neuroreceptors. And cause irritability, insomnia and other issues in the short term.

Excess serotonin can result in Serotonin Syndrome which can kill you. I can provide countless other examples of irresponsible nootropic use and out-of-whack neurotransmitter levels.

But your brain is a beautifully designed piece of equipment. Neuroplasticity and common sense can salvage most mistakes. Caution is always advised.

Side Effects

Every nootropic article on our List of Nootropics has a “Side Effects” section. Always assume that anything you do to alter brain chemistry or metabolism can have adverse effects.

Most neurohackers will not experience adverse effects for a single nootropic. But more sensitive individuals may experience dizziness, headaches, insomnia, migraines, rashes and many other adverse reactions.

And why we always say YMMV because everyone’s body chemistry and metabolism is different. If you experience a side effect to one nootropic, stop using it. And try something else. Experimentation is key to optimizing cognition.

Tolerance & Cycling

We mentioned “Dependence” earlier in this article which ties in somewhat with tolerance.

Tolerance is loosely defined as not getting the same benefit out of a nootropic with consistent and/or long-term use.

The “placebo effect” is applicable to nootropic usage and some can develop a psychological dependence on a nootropic. Thinking you’ll have a memory problem for example if you don’t take your daily stack can be very real. Even though the mechanism of action of that nootropic or stack proves otherwise.

Some nootropics with a ‘stimulant’ effect can produce a real tolerance issue. Experienced neurohackers will cycle Aniracetam for example. And take a 2-day per week ‘holiday’ to avoid tolerance.

Tolerance happens when your brain adjusts to using a certain nootropic. And as it adjusts, it can become less effective over time. The temptation is to increase your dosage to achieve the same effect. And is nearly always a very bad idea.

Taking higher than recommended doses of a nootropic can often be toxic to your brain. My recommendation is to never, ever exceed recommended doses for any nootropic. The least that can happen is a decline in quality of life. The worst is permanent brain damage.


Most neurohackers will not experience withdrawal symptoms when they stop using a nootropic. Most nootropics are completely safe to use without the worry of withdrawal symptoms.

But a few will feel like they’re going through withdrawal. Some nootropics like Phenibut which affects GABA levels in your brain can induce withdrawal symptoms. Nicotine is another that can be very addictive and can certainly cause withdrawal symptoms when you stop using it.

Read the user reviews, forum comments, and “How does it feel” section for each of my nootropic reviews. And you’ll get a sense for which nootropics may lead to withdrawal symptoms.


Nootropics Expert Tested and ApprovedNootropics are generally safe to use and most will not produce adverse side effects or cognition problems even with long-term use.

But it is your responsibility to use nootropics safely. Read the user reviews and forums and see what others are saying. Carefully review each nootropic review here on Nootropics Expert before adding it to your stack.

Always follow recommended dosages and start with the lowest dose possible to see how your body reacts. Be aware of possible interactions and contraindications with other prescription and non-prescription drugs.

More is not better when it comes to neurohacking. Dosage guidelines are based on decades of nootropic use and personal experience. You’ll experience the opposite effect or get no benefit by over-dosing.

Pay attention to cycling recommendations, and using certain nootropics on an as-needed basis. If your gut is telling you to stay away from a certain supplement, then don’t take it.

Nootropics are generally safe to use to optimize brain function. But caution is always advised.

As an Amazon Associate I earn from qualifying purchases. This post may also contain other affiliate links and I will be compensated if you make a purchase after clicking on my links.

[i] Billioti de Gage S., Bégaud B., Bazin F., Verdoux H., Dartigues J.F., Pérès K., Kurth T., Pariente A. “Benzodiazepine use and risk of dementia: prospective population based study.” BMJ. 2012 Sep 27;345:e6231. (source)

[ii] Ho B.C., Andreasen N.C., Ziebell S., Pierson R., Magnotta V. “Long-term antipsychotic treatment and brain volumes: a longitudinal study of first-episode schizophrenia.” Archives of General Psychiatry. 2011 Feb;68(2):128-37 (source)

[iii] Gray S.L., Anderson M.L., Dublin S. et al. “Cumulative Use of Strong Anticholinergics and Incident Dementia” JAMA Internal Medicine March 2015 (source)

Subscribe to the Nootropics Expert newsletter

Keep up to date with the latest developments in the nootropics space.

Head First 2nd Editon

The Award Winning Guide to Healing & Optimizing Your Brain with Nootropic Supplements.

Head First 2nd Edition

NEW! Eliminate Brain Fog, Low Energy, Moodiness, Difficulty Sleeping, Memory Loss or Anxiety. Available on Amazon, Barnes & Noble, Apple Books, Walmart and more...

Where to Buy Nootropics

Wondering where to buy the best nootropic supplements? Well, you’re in the right place. Because here you will find the nootropic supplements that I personally use and recommend. Each supplement has a link to the company store and product that I use. I also include a link to my full review for each supplement here […]

The Definitive Guide to Nootropics

Nootropics can help increase your memory, boost learning ability, improve your mood and assist overall brain function. If you’re new to nootropics, or wonder about the difference between a nootropic and a smart drug, then this page is for you. Here you’ll find the definition of a nootropic, how to pronounce the word “nootropic”, the […]

The Most Comprehensive Nootropics List

This is our big list of the most popular Nootropics in use today. Here you’ll learn what each nootropic is, what it does and suggested dosages. What is this List of Nootropics About? Nootropic supplements are cognitive enhancers aiming to improve brain function. Whether you are looking to treat mild cognitive impairment, improve mental focus, or biohack […]

Free Secrets of the Brain 3rd Edition

Get “Secrets of the Optimized Brain,” 92 nootropics to help you plan your Nootropic Stack when you sign up for my newsletter:

Join The Discussion - 21 comments

May 9, 2021

Any knowledge of counterindications between abilify and nootropics? (With Vyvanse included the mixture.)

“Some neurohackers can use a nootropic for years with no problems. And stop usage with no effect on cognitive function. While others can use a supplement for years.”
– I think there must be a mistake in the last sentence?

    David Tomen
    May 10, 2021

    Allan, I think you are referring to the section “Nootropic Safety” where I state, “Some neurohackers can use a nootropic for years with no problems. And stop usage with no effect on cognitive function. While others can use a supplement for years. And when discontinuing usage, experience significant cognitive impairment.” Is that the section you are referring too?

    I am sure there are contraindications between Abilify and some nootropics. Because when you look at that drug’s Pharmacology ( you see how it has an effect on nearly every neurotransmitter.

    Best to use a drug interaction checker like this one to be safe:

      May 10, 2021

      Hello David. No, it’s right here in the article, and as quoted. Thought it just a simple word repeation-typo I’d point out.

      And yes. Especially the dopamine antagonism which is common for anti-psychotics. It seems to make me very lazy, on top of all other experiences I already had.
      And yes I looked that up on – they only list interaction with lisdexamfetamine from what I could find, but it should surely mess with almost all the other ADHD meds.
      Regards, A.

Jackie gaspar
April 6, 2021

I took xmogen L-thyrosine
And my finger joints are cracking . It’s very painful
What do you suggest ?
The dose is 1.2g each
I took one a day

    David Tomen
    April 6, 2021

    Jackie, I am not familiar with that brand so can’t comment on their purity. It sounds like you are either reacting to something else that is in that capsule. Or the dose of L-Tyrosine is too high for you. Try half that dose and see if the same thing happens.

Keith Lockwood
March 28, 2021

How do I get Vital Info concerning the Contraindications between the Nootropic stack Mind Lab Pro that I would like to try, BUT I take “Remeron” for Depression & “Zanax” for bad Anxiety & occasional Panic Attacks ? I feel Lost trying to find out these VITAL Required Info’s.

    David Tomen
    March 28, 2021

    Keith, make a list of each ingredient in Mind Lab Pro. Then look up each of the drugs you are using in this checker: And scroll down the list and see if any of the ingredients are on that list.

December 31, 2020

Thank you for taking your time with this, very comprehensive and helpful!

    David Tomen
    December 31, 2020

    You are welcome sir.

Jeanne Combs
October 9, 2020

I am brand new to all of this. The last 2 years I’ve had a steady decline of cognitive issues. Namely getting lost driving, concentrating, forgetting things quickly. I have done Bookkeeping for 30+ years. My employer says I’m making too many mistakes and asking too many questions. So I have this little cycle going on: I am aware I am making mistakes so I am trying harder looking over my work twice. I know that my work is being reviewed and if they find anything it is brought to my attention. The little cycle begins and I get upset because I made a mistake, scared to make another mistake, I get emotional…you get the idea.
I’ve seen a Neurologist. He did an MRI and didn’t see any physical reason why this could be occurring. I even went to a Neuropsychiatric doctor. Same thing. Not sure why. My B and D levels were low. I have increased them with supplements. My TSH was within normal limits.
I have been on Wellbutrin 300mg (depression) and Trazadone 100mg (to stay asleep) for some time now. I have spent a lot of money with no results. My situation has not improved. I have been walking and eating smaller portions. I have lost 45lbs in the 7 months. I am doing everything I can. I am starting to feel like I am at the end of my rope. I’d eat dirt if someone said it would help.

    David Tomen
    October 11, 2020

    Jeanne, sounds like you are going through what every other human on the planet goes through as we get older. For some it happens at a younger age than others. But it will happen no matter what. Unless you intervene and do something about it.

    I went through the same thing with two different neurologists about 7 years ago. Both tested me for Alzheimer’s but didn’t find anything. Said they saw nothing wrong. And couldn’t do anything to bring my memory back. So I was on my own. And fixed it with nootropic supplements.

    I suggest you carefully read through this article on aging: Choose a couple of supplements from each category and start using them as recommended.

    Everything you need is on this website. It’s all backed by science and hundreds of thousands of people around the world are using these nootropic supplements to fix their brain. Just like you. It will take work and dedication to get results. But you will experience results if you are willing.

    If you need more help I suggest setting up a consultation with me here:

Anne Goggans
August 22, 2019

Hi David. I have a mast cell issue, and am sensitive to histamines. I think regular old Piracetam has made me a little itchy and hived me up a little. This makes me soooo sad, because after Lyme suite of infections and toxic mold exposure, I feel like someone is clearing the smog from my brain and turning on the lights. Do you know which Racetams are less likely to affect histamine binding, sensitivity, or release? I’m just heartbroken because it seemed like I had such a wonderful answer, but mold exposure has left me very sensitive. The ONLY thing I can find anywhere about Racetams and histamine response is with Aniracetam and some brain chemistry things that might do this. I took less than 1/8th tsp to try and it seemed fine. I did have a brief moment of panic, but it passed to a day of feeling very good other than hives and itching.
Thanks so much for your input, Anne

    David Tomen
    August 23, 2019

    Anne, until you get histamine under control you should likely avoid any of the racetams, nootropics with stimulant action and choline supplements. I’d suggest experimenting with some of the adaptogens for now.

    Please see my post on brain fog for other ideas:

      August 24, 2019

      I’m on those, thank you. Sigh, I was hoping to take advantage of the healing properties of Racetams and to help with brain fatigue and sluggishness. Is it the amine activity I look out for?
      Thanks again, Anne

        David Tomen
        August 25, 2019

        Anne, it’s aggravating already high histamine that seems to be the problem.

    September 3, 2019

    Disclaimer, I’m no professional. But how about using antihistamine at the same time?
    I’ve had CFS after a mononucleosis infection combined with high stress. For my brainfog fish oil (good quality is important) has been the best supplement. ALCAR has also been helpful.
    By the way, antidepressants also increase nerve growth factor, so if your mood/motivation is low you might want to try it.

      David Tomen
      September 4, 2019

      Magnus, I think one of the biggest reasons people come to Nootropics Expert is because they are sick and tired of the side effects caused by antihistamines and antidepressants. So yes, recent research suggests that antidepressants may increase nerve growth factor. But we have far safer ways to do that with nootropics:

Kieran Mckenna
March 10, 2019

Hi David,

I just came across your site a few days ago and think its great!

I’ve been taking the below stack for almost a year now with good results.

I start my day off with a bulletproof coffee then take the following:

Curcumin – Smarter Nutrition
Magnesium L- Threonate – Double Woods 2000mg (1000mg AM 1000mg PM)
Vitamin D – Viva 5000 IU
Vitamin C – Vitamin Shop 1000mg
Vitamin B Complex – Devine Bounty (High Potency Formula)
Polyphenol blend – Bulletproof
CoQ10 – Qunol 100mg
Omega 3 – Brain Power EPA 800mg DHA 600mg.

Before lunch I drink Athletic Greens Ultimate Daily.

I recently added Acetyl L-Carnitine – Divine Bounty 1200mg to the stack and had negative results. it caused major brain fog! I experimented with reducing the dosage to 600mg but I still felt like someone hit me with a dumb stick.. I stopped taking it and went back to feeling great! do you have any idea why this was?

After reading some of the blog posts I am thinking about adding:

CDP Choline – Double Woods 300mg
Phosphatidylserine – Double Woods 300mg
PQQ – Jarrow 10mg
N-Acetyl L-tyrosine – Jarrow 350mg (Twice a day)

What do you think?

I have recently been prescribed Modafinil. I don’t plan on taking it every day but my job demands that I work non traditional hours. The stack I have been taking has made me perform well. However, somedays I need something extra to keep me alert.

Is their anything that might not go well with Modafinil?

Thanks in advance for your assistance!

    David Tomen
    March 10, 2019

    Keiran, not sure why ALCAR would cause that reaction in you. Could be a bad supplement. I’m not familiar with that manufacturer so you may want to try one of the better known brands like Bulk Supplements, NOW Foods or Nutricost. Just make sure it hasn’t got any additives in it. Or it could be this supplement is not for you.

    Your second list looks good. You may want to save some money and get everything but PQQ in Mind Lab Pro:

October 27, 2016

Really well-written and informative column David

    David Tomen
    October 28, 2016

    Thank you Ron. Much appreciated.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.