Interactions on record — worth a quick check against your medications. Check your meds →
Dietary supplement

L-Theanine Calm Caps Ingredients & Drug Interactions

by Nature's Truth

L-Theanine Calm Caps label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking L-Theanine Calm Caps against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Moderate

L-Theanine Calm Caps is a dietary supplement by Nature's Truth with 4 active ingredients. Its ingredients are commonly taken for anxiety and stress, relaxation and calm, sleep support.Based on those ingredients, 1,419 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Ashwagandha, Chamomile, Passion Flower. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against L-Theanine Calm Caps by Nature's Truth

Ask about any prescription or over-the-counter medication and we check it for interactions with L-Theanine Calm Caps by Nature's Truth — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of L-Theanine Calm Caps by Nature's Truth

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Aug 13, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 4 of its 4 active ingredients.
  • “Ashwagandha” is listed as a grouped ingredient — the label gives one combined amount (50 mg) without saying how much of each component you get.
  • “Chamomile” is listed as a grouped ingredient — the label gives one combined amount (50 mg) without saying how much of each component you get.
  • “Passion Flower” is listed as a grouped ingredient — the label gives one combined amount (25 mg) without saying how much of each component you get.

This product contains 4 active ingredients. L-theanine is an amino acid from tea that may support calm and focus.

Ashwagandha root extract is an adaptogen traditionally used to ease stress and support sleep. German chamomile flower extract brings mild calming properties, and passion flower aerial extract rounds out the blend with additional relaxation support.

The capsules also contain inactive ingredients—cellulose, magnesium stearate, and silica—which are common binders and fillers.

Does it work?

Moderate evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Moderate

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: relaxed, calm mood support.
  • We looked for evidence on: Anxiety, Generalized anxiety disorder (GAD), Adjustment disorders, Pre-procedural anxiety, Insomnia, Benzodiazepine withdrawal — and 3 related terms.
  • The strongest evidence on file: Passion Flower is rated "Possibly Effective" for Pre-procedural anxiety (Natural Medicines).
  • Also on file: Passion Flower is rated "Possibly Effective" for Insomnia.
  • Also on file: Ashwagandha is rated "Possibly Effective" for Anxiety, Generalized anxiety disorder (GAD), Insomnia, Stress.

L-theanine is possibly effective for cognitive function, though evidence for age-related cognitive decline, Alzheimer's disease, and anxiety disorders is insufficient to rate. Ashwagandha shines for insomnia, anxiety, stress, and generalized anxiety disorder—all rated possibly effective—but evidence for bipolar disorder is insufficient.

German chamomile lacks sufficient reliable evidence for hay fever, sexual dysfunction, anxiety, and ADHD. Passion flower is possibly effective for insomnia and pre-procedural anxiety, but evidence for alcohol use disorder and benzodiazepine withdrawal remains insufficient to rate.

The evidence, ingredient by ingredient Theanine Ashwagandha German Chamomile Passion Flower

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 4 of the 4 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 4 of 4.
  • General safety write-ups exist for 4 of 4.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

L-theanine is generally well tolerated in healthy adults for short-term use, though long-term safety hasn't been well studied. It may cause headaches, drowsiness, or increased dream activity.

Ashwagandha is generally well tolerated short-term, but quality and long-term safety data are limited; it can occasionally cause diarrhea, nausea, or vomiting at typical doses, and rarely has been linked to liver problems. German chamomile is generally well tolerated but can trigger allergic reactions—especially in people sensitive to ragweed—and may cause allergic dermatitis or severe reactions in sensitive individuals.

Passion flower is generally well tolerated short-term and may cause drowsiness, dizziness, or confusion; rare allergic reactions have been reported. For pregnancy, L-theanine and German chamomile lack enough safety data—talk with your doctor before use.

Ashwagandha is traditionally thought to risk miscarriage and should be avoided in pregnancy. Passion flower is possibly unsafe in pregnancy due to lack of safety data and potential effects on the uterus.

For breastfeeding, all four ingredients lack sufficient safety information—check with your doctor or pharmacist before use.

Side effects, ingredient by ingredient Theanine Ashwagandha German Chamomile Passion Flower

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 4 of the 4 matched ingredients can interact with medications — Passion Flower, German Chamomile, Ashwagandha, Theanine.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications.
  • For scale: 1,420 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, check with your doctor or pharmacist if you take any of the following: blood pressure drugs (antihypertensives)—ashwagandha and L-theanine may lower blood pressure further. Sedatives, anti-anxiety drugs, or sleep aids—all four ingredients may increase drowsiness.

Diabetes medications—ashwagandha may lower blood sugar. Thyroid medication—ashwagandha may boost thyroid hormone effects.

Warfarin or other blood thinners—German chamomile may increase bleeding risk. Tamoxifen or other hormone-sensitive drugs, or oral birth control—German chamomile may reduce their effectiveness.

Drugs metabolized by liver enzymes (CYP2D6, CYP2C9, CYP3A4)—German chamomile may slow their clearance. Immunosuppressants—ashwagandha may weaken them.

Drugs that harm the liver—ashwagandha may increase liver damage risk.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with some supporting evidence for its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

This product blends four calming ingredients and may appeal to you if you're looking for support with stress, anxiety, or sleep—particularly the ashwagandha and passion flower components, which have the strongest evidence for these uses. However, if you take blood pressure medications, diabetes drugs, blood thinners like warfarin, thyroid medication, liver-metabolized drugs, or anti-anxiety and sleep aids, you'll need to talk it over with your doctor or pharmacist before starting, since the risks are real.

If you're pregnant, nursing, or have liver disease, check with your doctor or pharmacist first.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 4 of 4 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Feb 22, 2024.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about L-Theanine Calm Caps, straight from the product label.

Brand Nature's Truth
Barcode (UPC) 840093113986
Net contents 90 Vegetarian Capsule(s)
Market status On market
Date entered into DSLD Feb 22, 2024
DSLD ID 306736
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Vegetarian, Adult (18 - 50 Years), Women (not pregnant or lactating), Gluten Free, Dairy Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for L-Theanine Calm Caps by Nature's Truth, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
2 Vegetarian Capsule(s)
Maximum serving Sizes:
2 Vegetarian Capsule(s)
Servings per container
45
UPC/BARCODE
840093113986
IngredientAmount% DV
L-Theanine200 mg--
Ashwagandha50 mg--
Ashwagandha Root Extract 12.5 mg--
Chamomile50 mg--
Chamomile Flower Extract12.5 mg--
Passion Flower25 mg--
Passion Flower aerial Extract6.25 mg--

Other ingredients: Cellulose, Vegetarian Capsule, Magnesium Stearate, Silica

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Seals/Symbols

100% Quality Satisfaction guarantee

Our Non-GMO Pledge Visit our website

Formula

L-Theanine Calm Caps plus Passion flower, ashwagandha & chamomile

Formulation

Gluten free Non GMO

Supports a relaxed, calm mood

No gluten, wheat, yeast, milk, lactose, soy, artificial color, artificial flavor, artificial sweetener, preservatives. Non-GMO

Vegetarian formula

FDA Statement of Identity

Dietary Supplement

FDA Disclaimer Statement

This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

Suggested/Recommended/Usage/Directions

Directions: For adults, take two (2) vegetarian capsules daily, preferably 30 minutes before bedtime or as needed.

Precautions

Warning: Not intended for use by pregnant or nursing women. If you are taking any medications or surgical procedure or have any medical condition, consult your doctor before use.

Avoid this product if you are allergic to ragweed or daisy-like flowers.

If any adverse reactions occur, immediately stop using this product and consult your doctor. Excessive consumption may impair ability to drive a motor vehicle or operate heavy equipment. If seal under cap is damaged or missing, don not use.

Not intended for use by persons under age of 18. Keep out of reach of children.

Storage

Store in a cool, dry place.

Brand IP Statement(s)

Copyright 2021 Nature's Truth LLC

General Statements

Vitamins

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

L-Theanine Calm Caps by Nature's Truth label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

L-Theanine Calm Caps label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in L-Theanine Calm Caps by Nature's Truth

These are the 4 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Vegetarian Capsule(s) Dosage formCapsule Servings per container45 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

L-Theanine

Interacts with
565 drugs
200 mg per serving

Theanine (usually L-theanine) is an amino acid found naturally in tea leaves that many people take to feel calmer and less stressed without strong dro...

L-Theanine monograph & interactions

Ashwagandha

Interacts with
1,372 drugs
50 mg per serving

Ashwagandha is an Ayurvedic herb most often taken to help with stress, anxiety, and sleep, and some small studies suggest it may help, though the evid...

Ashwagandha monograph & interactions

Chamomile

Interacts with
960 drugs
50 mg per serving Form: Matricaria recutita

German chamomile is a widely used herbal remedy taken mainly as a tea for calming, sleep, and digestive complaints. Early research suggests possible b...

Chamomile monograph & interactions

Passion Flower

Interacts with
836 drugs
25 mg per serving

Passion flower is a traditional calming herb that many people use for anxiety and sleep. Early studies hint it may help with mild anxiety and restless...

Passion Flower monograph & interactions

Other (inactive) ingredients: Cellulose, Vegetarian Capsule, Magnesium Stearate, Silica. These complete the product’s ingredient list but are not active constituents.

Interaction report

L-Theanine Calm Caps by Nature's Truth Drug Interactions

Want to check YOUR meds against L-Theanine Calm Caps?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
1,419Drugs
1,360 Moderate 59 Minor

Ingredients driving the most interactions

Ashwagandha 1,372
Chamomile 960
Passion Flower 836
L-Theanine 565

Individual Drug Interactions

The ingredients in L-Theanine Calm Caps interact with 1,419 drugs. Click any drug to see the details.

4 of the 4 ingredients in L-Theanine Calm Caps interact with drugs. Each result below shows which ingredient is responsible. Ashwagandha Chamomile Passion Flower L-Theanine

Each ingredient & the kinds of drugs it affects

For each ingredient in L-Theanine Calm Caps with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Ashwagandha10 drug types · 1,372 drugs

Antidiabetes Drugs

Theoretically, taking ashwagandha with antidiabetes drugs might increase the risk of hypoglycemia.
There is preliminary clinical evidence suggesting that ashwagandha might lower blood glucose levels. Theoretically, ashwagandha might have additive effects when used with antidiabetes drugs and increase the risk of hypoglycemia.

Likelihood Possible Evidence B
Antihypertensive Drugs

Theoretically, taking ashwagandha with antihypertensive drugs might increase the risk of hypotension.
Animal research suggests that ashwagandha might lower systolic and diastolic blood pressure. Theoretically, ashwagandha might have additive effects when used with antihypertensive drugs and increase the risk of hypotension.

Likelihood Possible Evidence D
Benzodiazepines

Theoretically, taking ashwagandha might increase the sedative effects of benzodiazepines.
There is preliminary evidence that ashwagandha might have an additive effect with diazepam (Valium) and clonazepam (Klonopin). This may also occur with other benzodiazepines.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, taking ashwagandha might increase the sedative effects of CNS depressants.
Ashwagandha seems to have sedative effects. Theoretically, this may potentiate the effects of barbiturates, other sedatives, and anxiolytics.

Likelihood Possible Evidence D
Hepatotoxic Drugs

Theoretically, taking ashwagandha with hepatotoxic drugs might increase the risk of liver damage.
Ashwagandha has been linked to cases of acute hepatitis, liver failure, hepatic encephalopathy, autoimmune hepatitis, the need for liver transplantation, and death due to liver failure.

Likelihood Possible Evidence D
Immunosuppressants

Theoretically, taking ashwagandha might decrease the effects of immunosuppressants.
Ashwagandha has demonstrated immunostimulant effects in humans. Animal research has shown that ashwagandha can attenuate the immunosuppression caused by cyclophosphamide.

Likelihood Possible Evidence D
Thyroid Hormone

Ashwagandha might increase the effects and adverse effects of thyroid hormone.
Concomitant use of ashwagandha with thyroid hormones may cause additive therapeutic and adverse effects. Preliminary clinical research and animal studies suggest that ashwagandha boosts thyroid hormone synthesis and secretion. In one clinical study, ashwagandha increased triiodothyronine (T3) and thyroxine (T4) levels by 41.5% and 19.6%, respectively, and reduced serum TSH levels by 17.4% from baseline in adults with subclinical hypothyroidism.

Likelihood Probable Evidence B
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, ashwagandha might decrease the levels and clinical effects of CYP1A2 substrates.
In vitro research shows that ashwagandha extract induces CYP1A2 enzymes.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, ashwagandha might decrease the levels and clinical effects of CYP3A4 substrates.
In vitro research shows that ashwagandha extract induces CYP3A4 enzymes.

Likelihood Possible Evidence D
Serotonergic Drugs

Some animal studies have reported that ashwagandha can enhance serotonergic transmission by altering certain serotonin (5-HT) receptors. However, there is no evidence to suggest that ashwagandha increases the risk of serotonin-related effects, and there have been no published case reports of serotonin syndrome when combined with other serotonergic drugs. Nevertheless, due to the lack of extensive studies on the matter and the fact that ashwagandha appears to affect serotonergic pathways, it would be prudent to exercise caution when combining it with drugs that affect serotonin. [References: - Effects of Withania somnifera (Ashwaga ndha) on Stress and the Stress-Related Neuropsychiatric Disorders Anxiety, Depression, and Insomnia. Curr Neuropharmacol. 2021 Sep 14; 19: 1468–1495. - A Prospective, Randomized Double-Blind, Placebo-Controlled Study of Safety and Efficacy of a High-Concentration Full-Spectrum Extract of Ashwagandha Root in Reducing Stress and Anxiety in Adults. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3573577/]

Likelihood Possible Evidence C
Ashwagandha full monograph & interactions

Chamomile9 drug types · 960 drugs

Cns Depressants

Theoretically, German chamomile might have additive effects when used with CNS depressants.
German chamomile has mild sedative effects. Theoretically, concomitant use with drugs with sedative properties can cause additive effects and side effects.

Likelihood Possible Evidence D
Contraceptive Drugs

Theoretically, large amounts of German chamomile might reduce the effectiveness of oral contraceptives.
In vitro, German chamomile has demonstrated antiestrogenic activity. Theoretically, concomitant use of large amounts of German chamomile might interfere with contraceptive drugs through competition for estrogen receptors.

Likelihood Possible Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, German chamomile might inhibit CYP2C9 and increase levels of drugs metabolized by these enzymes.
In vitro evidence shows that German chamomile might inhibit CYP2C9. So far, this interaction has not been reported in humans. However, there might be an increase in the levels of drugs metabolized by CYP2C9 in patients taking German chamomile.

Likelihood Possible Evidence D
Cytochrome P450 2D6 (Cyp2D6) Substrates

Theoretically, German chamomile might inhibit CYP2D6 and increase levels of drugs metabolized by these enzymes.
In vitro evidence shows that German chamomile might inhibit CYP2D6. So far, this interaction has not been reported in humans. However, there might be an increase in the levels of drugs metabolized by CYP2D6 in patients taking German chamomile.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, German chamomile might inhibit CYP3A4 and increase levels of drugs metabolized by these enzymes.
In vitro evidence shows that German chamomile might inhibit CYP3A4. So far, this interaction has not been reported in humans. However, there might be an increase in the levels of drugs metabolized by CYP3A4 in patients taking German chamomile.

Likelihood Possible Evidence D
Estrogens

Theoretically, large amounts of German chamomile might reduce the effectiveness of estrogens.
In vitro, German chamomile has demonstrated antiestrogenic activity. Theoretically, large amounts of German chamomile might interfere with hormone replacement therapy through competition for estrogen receptors.

Likelihood Possible Evidence D
Tamoxifen (Nolvadex)

Theoretically, large amounts of German chamomile might interfere with the activity of tamoxifen.
In vitro, German chamomile has demonstrated antiestrogenic activity.

Likelihood Possible Evidence D
Warfarin (Coumadin)

German chamomile might increase the effects of warfarin and increase the risk of bleeding.
In one case, a 70-year-old female taking warfarin developed retroperitoneal hematoma and bilateral recti muscle bleeding along with an INR of 7.9 following ingestion of German chamomile tea 4-5 cups daily and use of a topical chamomile-based lotion applied 4-5 times daily.

Likelihood Possible Evidence D
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, German chamomile might inhibit CYP1A2 and increase levels of drugs metabolized by these enzymes.
In vitro and animal research shows that German chamomile might inhibit CYP1A2. So far, this interaction has not been reported in humans. However, there might be an increase in the levels of drugs metabolized by CYP1A2 in patients taking German chamomile.

Likelihood Possible Evidence D
Chamomile full monograph & interactions

Passion Flower3 drug types · 836 drugs

Cns Depressants

Concomitant use of passion flower with sedative drugs might cause additive effects and side effects.
Research in animals and humans shows that passion flower has sedative effects which can be additive when used with sedative medications like lorazepam.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, passion flower might decrease the effects of CYP3A4 substrates.
In vitro research suggests that passion flower can induce CYP3A4 enzymes, albeit to a much lower degree than rifampin, a known CYP3A4 inducer.

Likelihood Possible Evidence D
Organic Anion-Transporting Polypeptide Substrates (Oatp)

Theoretically, passion flower might reduce the bioavailability of OATP2B1 and OATP1A2 substrates.
In vitro research shows that the passion flower constituents apigenin and vitexin inhibit OATP2B1 and OATP1A2. This inhibition may be dose-dependent. One specific high-flavonoid passion flower extract (Valverde) seems to inhibit OATP2B1 and OATP1A2, while another extract with a lower flavonoid concentration (Arkocaps) shows less potent inhibition. OATPs are responsible for the uptake of drugs and other compounds into the body; however, the specific activities of OATP2B1 and OATP1A2 are not well characterized.

Likelihood Possible Evidence D
Passion Flower full monograph & interactions

L-Theanine3 drug types · 565 drugs

Antihypertensive Drugs

Theanine might lower blood pressure, potentiating the effects of antihypertensive drugs.
Animal research shows that theanine can lower blood pressure in spontaneously hypertensive animals. Theoretically, concomitant use of theanine and antihypertensive drugs might potentiate the antihypertensive activity.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, theanine might have additive sedative effects when used in conjunction with CNS depressants. However, it is unclear if this concern is clinically relevant.
Theoretically, theanine may compete with glutamate and/or increase plasma gamma-aminobutyric acid (GABA) levels, which could cause CNS depression. In one clinical study, some subjects taking oral theanine reported drowsiness.

Likelihood Unlikely Evidence D
Serotonergic Drugs

Clinical studies regarding the effects of L-theanine on serotonin levels are conflicting. Some studies suggest it can increase serotonin levels in the brain while others report that it may decrease them. Nevertheless, there have been no reports of l-theanine being a causative agent in serotonergic-related side effects or serotonin syndrome.

Likelihood Unlikely Evidence C
L-Theanine full monograph & interactions
The maker

Brand information

Manufacturer and brand details for L-Theanine Calm Caps, from the product label.

Nature's Truth

See all Nature's Truth products
Name
Nature's Truth LLC
City
Ronkonkoma
State
NY
ZipCode
11779
Phone Number
1-844-544-1030
Web Address
naturestruthproducts.com
Pharmacist Counseling Corner

L-Theanine Calm Caps by Nature's Truth: Common Questions

Does L-Theanine Calm Caps by Nature's Truth interact with any medications?
Yes. Based on its ingredients, L-Theanine Calm Caps has a known interaction with 1,419 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
L-Theanine Calm Caps contains 4 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Is this safe to take during pregnancy?
No—ashwagandha is traditionally thought to risk miscarriage and should be avoided. L-theanine, German chamomile, and passion flower lack enough safety data during pregnancy. Talk with your doctor or pharmacist for personalized advice before use.
Can I take this while breastfeeding?
All four ingredients in this product lack sufficient safety information for breastfeeding. Talk with your doctor or pharmacist first to decide if it's right for you.
What side effects might I experience?
L-theanine may cause headaches, drowsiness, or increased dream activity. Ashwagandha can cause diarrhea, nausea, or drowsiness. German chamomile may trigger allergic reactions in people sensitive to ragweed. Passion flower may cause dizziness, drowsiness, or confusion. All ingredients may add to sedation if you're taking sleep aids or anti-anxiety drugs.
Does L-theanine actually work for anxiety?
Evidence for L-theanine in generalized anxiety disorder is insufficient to rate. However, ashwagandha and passion flower in this blend are both rated possibly effective for anxiety, so the combination may help, but individual results vary.
Will this help me sleep?
Ashwagandha and passion flower are both rated possibly effective for insomnia, and German chamomile and L-theanine have mild sedative properties, so yes—this blend is designed to support sleep. However, long-term safety data for L-theanine and ashwagandha are limited.
Is this safe to take with my blood pressure medication?
Both ashwagandha and L-theanine may lower blood pressure, so combining them with blood pressure drugs could cause your pressure to drop too far. Talk with your doctor or pharmacist before taking this product if you're on blood pressure medication.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

L-Theanine Calm Caps label
Go deeper

The Full Monographs Behind L-Theanine Calm Caps’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Theanine

Interacts with 565 drugs

Theanine (usually L-theanine) is an amino acid found naturally in tea leaves that many people take to feel calmer and less stressed without strong drowsiness. Early research suggests it may...

Read the full Theanine monograph → Herb & supplement monograph

Ashwagandha

Interacts with 1,372 drugs

Ashwagandha is an Ayurvedic herb most often taken to help with stress, anxiety, and sleep, and some small studies suggest it may help, though the evidence is still limited. It is generally w...

Read the full Ashwagandha monograph → Herb & supplement monograph

German Chamomile

Interacts with 960 drugs

German chamomile is a widely used herbal remedy taken mainly as a tea for calming, sleep, and digestive complaints. Early research suggests possible benefits for mild anxiety and some skin o...

Read the full German Chamomile monograph → Herb & supplement monograph

Passion Flower

Interacts with 836 drugs

Passion flower is a traditional calming herb that many people use for anxiety and sleep. Early studies hint it may help with mild anxiety and restlessness, but the evidence is limited and mo...

Read the full Passion Flower monograph →
Sources

Sources & How We Checked

L-Theanine Calm Caps's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 72 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Theanine 6 references
  1. Yokogoshi H, Kobayashi M. Hypotensive effect of gamma-glutamylethylamide in spontaneously hypertensive rats. Life Sci 1998;62:1065-8.
  2. Haskell, C. F., Kennedy, D. O., Milne, A. L., Wesnes, K. A., and Scholey, A. B. The effects of L-theanine, caffeine and their combination on cognition and mood. Biol.Psychol. 2008;77(2):113-122. PubMed
  3. Yokogoshi, H., Kato, Y., Sagesaka, Y. M., Takihara-Matsuura, T., Kakuda, T., and Takeuchi, N. Reduction effect of theanine on blood pressure and brain 5-hydroxyindoles in spontaneously hypertensive rats. Biosci.Biotechnol.Biochem. 1995;59(4):615-618. PubMed
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Ashwagandha 32 references
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German Chamomile 15 references
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Passion Flower 19 references
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  2. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

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