Pristine L-Theanine 200mg is a capsule of 200 mg L-theanine, sold as a 150-count glass bottle and marketed by its maker for sleep, calm and focus support. As of October 29, 2026, the Amazon listing shows a one-time price of $16.99 for 150 capsules, which is $0.11 a capsule, and a subscription option that the listing says has no fees and can be skipped or cancelled at any time. The listing states that the item is non-returnable due to food safety reasons, so read the return details on your order before you pay. L-theanine is an amino acid found mainly in tea, and a 2019 study published in the journal Nutrients, as summarized by Live Momentous, found that stress-related scores, including sleep, decreased and cognitive scores improved after four weeks of L-theanine. This page covers what is in the bottle, what the research says, side effects, price and refund terms, buyer feedback, and how to buy from the listed seller.
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| What it is | L-theanine 200 mg capsules, 150 count, in a glass bottle |
| Who sells it | Listed as sold by FedPharm and shipped by Amazon; brand listed as PRISTINE’S |
| Price as shown | $16.99 one-time purchase for 150 capsules |
| Guarantee or returns | The listing says the item is non-returnable due to food safety reasons |
| How to contact the seller | Through Amazon Customer Service, reached from Your Orders |
| Product Page | Where to Buy |
What is Pristine L-Theanine 200mg and who sells it?
Also searched as pristine ltheanine 200mg. The listing names the product PRISTINE’S L-Theanine 200mg Capsules, Sleep & Calm Focus Support, 150 Count, and describes it as a relaxation and wind-down supplement. Its maker says it supports sleep, calm and focus.
The brand is listed as PRISTINE’S, with a “Visit the PRISTINE’S Store” link, and the listing describes it as a small business brand. On the listing, the item is sold by FedPharm and ships from Amazon. The listing also shows an Amazon’s Choice badge and “400+ bought in past month.”
What is in Pristine L-Theanine 200mg?
The listing gives these details. Where the listing does not publish an item, the table says so, so you know what to check on the bottle.
| Item | What the listing says |
|---|---|
| Active ingredient | L-theanine |
| Amount per capsule | 200 mg |
| Form | Capsules |
| Count | 150 capsules, listed as a 150 day supply |
| Container | Glass bottle |
| Other ingredients | Not published |
| Amounts of other ingredients | Not published |
| Label claims | Vegan, Non-GMO, Gluten-Free, Third-Party Tested |
L-theanine is an amino acid most commonly found in tea, according to Innerbody Research. Innerbody also explains that synthetic L-theanine is often made as a mix of the L and D forms, and that the D form can work against the L form. Its advice is to check the label or ask the company for proof of purity.
How does L-theanine work, and what does the research show?
In simple terms, L-theanine is thought to influence brain chemicals such as GABA, dopamine and serotonin, according to Live Momentous. Innerbody reports that animal studies show L-theanine can cross the blood-brain barrier, and that its sleep benefits are tied to its effect on stress. Innerbody notes that stress reduction is often measured by an increase in alpha wave activity in the brain.
Innerbody reports that a systematic review of L-theanine for sleep concluded that doses from 50 to 655 mg could improve sleep onset, total sleep time, sleep efficiency, sleep quality and next-day alertness. To see how reviews like this pool many studies, read what pooled trial reviews show (our research library).
| Study or review | What it looked at | What it found, as reported |
|---|---|---|
| 2019 study in Nutrients (cited by Live Momentous) | Four weeks of L-theanine | Stress-related scores, including depression, anxiety-trait and sleep, decreased; verbal fluency and executive function scores improved |
| 2021 research (cited by Live Momentous) | L-theanine and cognition | Possible gains in working memory, executive function and attention |
| Japanese study (cited by Innerbody) | 200 mg of L-theanine | Verbal and letter fluency improved under stress compared with placebo |
| Review of studies (cited by Innerbody) | Doses of 200 to 400 mg | Reduced self-reported stress, with improvements in stressor tasks, reaction time and brain wave activity |
| Relaxation study (cited by Innerbody) | Doses of 50 to 200 mg, measured 40 minutes after dosing | Increased alpha wave activity |
| Attention study (cited by Innerbody) | 200 mg alone or with 160 mg of caffeine | Improved attention and reaction time |
These are the studies reviewers cite, and their findings are worth reading before you decide. The 200 mg dose in this bottle matches the dose these reviewers describe as used in numerous studies.
Pros and cons of Pristine L-Theanine 200mg
| Pros | Cons |
|---|---|
| 200 mg of L-theanine per capsule, the dose Innerbody notes is used in numerous studies | The item is non-returnable due to food safety reasons, according to the listing |
| The listing says it is third-party tested, vegan, non-GMO and gluten-free | Other ingredients and their amounts are not published |
| 150 capsules at $0.11 each, per the listing | Innerbody notes limited human evidence on L-theanine’s potential effects on longevity and aging, and says more direct human research is needed there |
| Glass bottle packaging | Some buyers of L-theanine products report side effects, and some report worse sleep (see the feedback section below) |
| 4.6 out of 5 stars from 416 ratings on the listing |
Who is Pristine L-Theanine 200mg for, and who should skip it?
The maker markets it to people who want relaxation, a wind-down before sleep, and support for focus. If you want a single-ingredient L-theanine capsule and you are comfortable with the refund terms below, the listing gives you the facts to decide.
Innerbody says that L-theanine should be mostly safe for most people, and adds that it is always a good idea to talk to your doctor before starting any new supplement. Skip it for now, or ask a clinician first, if you take medicines or have a health condition. The MedlinePlus sleep disorders page advises checking with your provider before taking any medicine or supplement.
Side effects, safety and who should ask a clinician first
Buyers of L-theanine products on WebMD and Drugs.com describe the effects below. These are individual reports about L-theanine supplements in general, not about this brand, and they are not clinical studies.
| Reported effect | Where reviewers describe it |
|---|---|
| Heart palpitations, fast heartbeat or chest pain | Drugs.com reviews |
| Nausea, vomiting or diarrhea | WebMD and Drugs.com reviews |
| Headache, dizziness or fatigue | WebMD and Drugs.com reviews |
| Waking several times a night, or sleep getting worse | WebMD and Drugs.com reviews |
| Vivid dreams that faded within about a week | WebMD review |
Several reviewers stopped taking L-theanine after these effects, and one said they stopped after palpitations started. If you notice a new symptom, stop and call your clinician.
Caffeine and L-theanine are often discussed together. Innerbody says L-theanine can offset caffeine’s less pleasant effects. Harvard Health’s sleep interruption guide warns that caffeine blocks adenosine, a brain chemical that helps you sleep, and recommends going light on caffeine after early afternoon. It also lists drinking alcohol within four hours of bedtime as a common cause of disrupted sleep.
On medicines, the Cleveland Clinic’s insomnia guide notes that some medications can interact with others, and advises talking to a provider before taking herbs or supplements. Ask your clinician about any liver or kidney condition before you start, and ask a pharmacist to check your current medicines.
How should you take Pristine L-Theanine 200mg?
Follow the directions on the bottle label for dose and timing, and do not go above them. The listing text does not replace the label, so check the label for the number of capsules per day.
Buyers take L-theanine at different times. One WebMD reviewer took 100 mg about an hour before bed. A Live Momentous reviewer found it useful during the day, paired with morning coffee. A Drugs.com reviewer took 200 mg before leaving home. Choose the time that fits your schedule and track how you feel.
What do buyers say about Pristine L-Theanine 200mg?
The listing shows a 4.6 out of 5 star rating from 416 ratings. Read the written reviews on the listing for experiences with this brand specifically.
Across L-theanine in general, WebMD shows an overall rating of 4.4 from patient reviews. Drugs.com shows an average of 5.2 out of 10 from 158 reviews, with 42% of reviewers reporting a positive experience and 46% a negative one. Positive buyers describe a calmer mind during the day and better sleep at night. Negative buyers describe side effects, and some report that their sleep got worse.
How much does Pristine L-Theanine 200mg cost, and what does shipping add?
| Option | What you get | Price as shown | Per capsule |
|---|---|---|---|
| One-time purchase | 150 capsules, one bottle | $16.99 | $0.11 |
| Subscribe & Save | Delivery every 5 months, the default interval on the listing | Listed as saving up to 5% on auto-deliveries; check the exact subscription price at checkout | Check at checkout |
| Shipping on orders shipped by Amazon | Free delivery on orders shipped by Amazon over $35, or free for Prime members per the listing. A single $16.99 bottle is under $35, so check the shipping cost at checkout. | Check at checkout for a single bottle | Not applicable |
The subscription has no fees, according to the listing, and you can skip or cancel it at any time. Prime members get free delivery on a faster date, per the listing. Check the final total, including tax, at checkout before you confirm.
Refund, returns and cancelling: the exact terms and steps
The Amazon listing states that the item is non-returnable due to food safety reasons. The Amazon Customer Service page lists “Return Items You Ordered,” “Check status of a refund” and “Your Memberships and Subscriptions” under Your Orders, so these are the places to look.
- Open Your Orders and find the order for Pristine L-Theanine 200mg.
- Check the return option on the order. The listing says the item is non-returnable, so ask Amazon Customer Service what they can do before you rely on a refund.
- Amazon Customer Service lists a “Returns, Refunds and Product Support” topic. Ask them which options apply to this non-returnable item.
- To cancel a subscription, open Your Memberships and Subscriptions, or find Subscribe & Save in your account, and cancel the delivery there.
Is Pristine L-Theanine 200mg legit? Is it a scam?
You can check the basics yourself. The listing names FedPharm as the seller and Amazon as the shipper, which means your order runs through Amazon’s own order and returns system. Buying through that system keeps your order history, delivery updates and refund requests in one account. Use “Report Something Suspicious” on Amazon’s Customer Service page if anything about the listing looks wrong.
What you can verify yourself: the seller name on the order, the shipper, the bottle label, the lot number on the bottle, and the refund steps above. What you cannot verify from the listing alone: which lab tested the product. Ask the seller which lab tested it and for the certificate before you order. Do not buy from a listing where the seller or shipper differs from the one shown here without checking that listing’s terms first.
Where to buy Pristine L-Theanine 200mg, and how to avoid look-alike sellers
Buy from the listing where the item is sold by FedPharm and ships from Amazon. You can see the current listing at the Product Page. Compare the bottle size, capsule count and dose on the order page with the listing above. If any of those differ, pause and check before you pay.
How does Pristine L-Theanine 200mg compare with other options?
Here is how the L-theanine products cited by reviewers compare on dose, count and price as those reviewers listed them. Prices change, so check today’s price directly with the seller.
| Product | Dose | Count or size | Price as listed | Where the price comes from |
|---|---|---|---|---|
| Pristine L-Theanine 200mg | 200 mg per capsule | 150 capsules | $16.99 | Amazon listing |
| Momentous L-Theanine | 200 mg per capsule | 60 servings | $39.95 | Live Momentous |
| Now Foods L-Theanine | 100 mg per tablet | 90 tablets | $21.99 | Live Momentous |
| Bulk Supplements L-Theanine Powder | Powder | 100 g bag | $16.97 | Innerbody |
Doing nothing is also an option, and it has a clear path. The NHS insomnia guide explains that insomnia lasting three months or longer is called long-term insomnia. Cleveland Clinic describes cognitive behavioral therapy for insomnia, known as CBT-I, which uses strategies such as sleep restriction therapy and stimulus control and is led by psychologists or other professionals. For a food-based approach, see herbal tea for sleep or valerian root for sleep.
Why do I keep waking up at night, and why do I only stay asleep for a few hours?
Harvard Health’s sleep interruption guide lists alcohol within four hours of bedtime, eating within a few hours of bed, long afternoon naps and too much caffeine as common lifestyle causes of disrupted sleep. It also notes that waking early often reflects your sleep schedule rather than disrupted sleep. Changing these habits can help, sometimes quickly. If it keeps happening, the Cleveland Clinic’s guide lists waking in the middle of the night and having trouble falling back asleep among common insomnia symptoms.
Before you order
- Check the bottle label for the other ingredients and their amounts, which the listing does not publish.
- Ask the seller which form of L-theanine it uses and which lab tested the product.
- Read the return terms on your order, since the listing says the item is non-returnable due to food safety reasons.
- Check the price, the subscription price and the delivery interval at checkout before you confirm.
- If you take any medicine or have a health condition, ask your clinician or pharmacist before you start.
Short answers to your other questions
Is L-theanine worth it? That depends on what you want from it. The studies above point to calm, sleep and focus effects at 200 mg. At $0.11 a capsule, Pristine is priced below the $0.66 per capsule Live Momentous calculated for Momentous.
Is there a downside? Yes, as the cons above show: some buyers report side effects, some report worse sleep, and the listing says the item is non-returnable.
Should it be taken at night or in the morning? Buyers take it both ways. Follow the label, and choose the time that suits you.
What should I not mix it with? Harvard Health advises going light on caffeine after early afternoon and avoiding alcohol within four hours of bedtime. Ask your clinician about any medicine you take.
How long does it take to kick in for anxiety? A relaxation study cited by Innerbody measured effects 40 minutes after dosing. Drugs.com reviewers describe calm within about 45 minutes to an hour. These are individual reports, not a set timeline.
Is L-theanine hard on the liver or kidneys? If you have a liver or kidney condition, ask your clinician before you start.
Why can’t I stay asleep for four hours? Harvard Health notes that waking early often reflects your sleep schedule, and lists alcohol, late meals, naps and caffeine as common causes of interrupted sleep.
By the Global MH Summit Research Team