Interactions on record — worth a quick check against your medications. Based on 4 of 5 ingredients. Check your meds →
Dietary supplement

Somnolin Ingredients & Drug Interactions

by Metagenics

Somnolin label
See full label image
Tablet Or Pill Category: Other Combinations
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 23, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Somnolin 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

Somnolin is a dietary supplement by Metagenics with 5 active ingredients. Its ingredients are commonly taken for morning sickness in pregnancy, premenstrual syndrome (pms), preventing or treating b6 deficiency.Based on those ingredients, 592 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are L-Theanine, L-5-Hydroxytryptophan, Vitamin B6. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Somnolin by Metagenics

Ask about any prescription or over-the-counter medication and we check it for interactions with Somnolin by Metagenics — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Somnolin by Metagenics

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 Sep 10, 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 5 of its 5 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Somnolin contains five active ingredients designed to support sleep. Vitamin B6 supports nerve function and mood, L-theanine promotes calm and relaxation, vitamin B12 maintains energy and neurological health, and L-5-hydroxytryptophan (5-HTP) is a precursor to serotonin, the brain chemical involved in mood and sleep regulation.

The product also contains inactive ingredients — microcrystalline cellulose, cellulose, stearic acid, croscarmellose sodium, and silica — which serve as binders, fillers, and flow agents in the tablet.

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: promote restful relaxed state and relieve occasional sleeplessness.
  • We looked for evidence on: Insomnia, Circadian rhythm sleep disorders, Anxiety, Generalized anxiety disorder (GAD), Depression, Sleep quality — and 2 related terms.
  • The strongest evidence on file: 5-htp is rated "Possibly Effective" for Depression (Natural Medicines).
  • Also on file: Vitamin B12 is rated "Possibly Ineffective" for Circadian rhythm sleep disorders.
  • Also on file: 5-htp is rated "Insufficient Reliable Evidence To Rate" for Anxiety, Insomnia.

Evidence for this product's individual ingredients is mixed. Vitamin B6 is effective for B6 deficiency and sideroblastic anemia, and possibly effective for pregnancy-related nausea.

L-theanine is possibly effective for cognitive function, though evidence for anxiety and age-related decline is insufficient. Vitamin B12 is effective for B12 deficiency.

L-5-hydroxytryptophan is possibly effective for depression. The product as a whole — for sleep specifically — has no effectiveness rating in our data; we cannot tell you from these facts whether the combination works for insomnia or sleep quality.

The evidence, ingredient by ingredient Vitamin B6 Theanine Vitamin B12 5-htp

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.

Vitamin B6 is generally well tolerated at normal doses but can harm nerves at high doses or over long periods. L-theanine is generally well tolerated short-term in healthy adults, though long-term safety isn't well studied.

L-5-hydroxytryptophan is also generally well tolerated short-term but causes drowsiness and gastrointestinal side effects (nausea, diarrhea, abdominal pain) in some people, and rarely can trigger mood changes like hypomania or aggression. Vitamin B12 is generally very safe with no established upper limit.

For pregnancy, vitamin B6 carries mixed safety data (likely safe for some uses, possibly unsafe for others), and the safety data advise against L-theanine and 5-HTP during pregnancy and breastfeeding due to insufficient information. Vitamin B12 is considered safe and actually needed during pregnancy and breastfeeding at recommended amounts.

Side effects, ingredient by ingredient Vitamin B6 Theanine Vitamin B12 5-htp

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 — 5-htp, Vitamin B12, Vitamin B6, Theanine.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: Parkinson's medications.
  • For scale: 592 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 Somnolin, check with your doctor or pharmacist if you take serotonergic drugs (such as antidepressants, anti-anxiety, or migraine medications), blood pressure medications, seizure drugs (phenobarbital, phenytoin), the heart rhythm medication amiodarone, sedating medications, carbidopa (for Parkinson's disease), or metformin (for diabetes). These are the medication types with documented interactions with ingredients in this product.

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.

Somnolin might appeal to someone looking for a natural sleep aid combining calming and mood-supporting ingredients. If you take blood pressure medications, seizure drugs, antidepressants, other serotonergic drugs, sedating medications, the diabetes drug metformin, heart rhythm medication, or any Parkinson's medication, you'll want to check your exact list with your doctor or pharmacist before starting this product.

Pregnant or breastfeeding people should talk with their provider first, as two of the four active ingredients lack safety data for these stages. Work with your own doctor or pharmacist to decide if Somnolin fits your situation.

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

Assessment coverage: 4 of 5 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Nov 25, 2013.

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 Somnolin, straight from the product label.

Brand Metagenics
Net contents 30 Tablet(s)
Market status On market
Date entered into DSLD Nov 25, 2013
DSLD ID 27874
Product type Other Combinations
Supplement form Tablet Or Pill
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Vegetarian, Adult (18 - 50 Years)
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 Somnolin by Metagenics, 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 Tablet(s)
Maximum serving Sizes:
2 Tablet(s)
Servings per container
15
IngredientAmount% DV
Vitamin B640 mg2000%
L-Theanine200 mg--
Vitamin B12500 mcg8334%
L-5-Hydroxytryptophan200 mg--
Folate400 mcg100%

Other ingredients: Microcrystalline Cellulose, Cellulose, Stearic Acid, Croscarmellose Sodium, 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.
Brand IP Statement(s)

Somnolin(R) features a complementary blend of nutrients to promote a restful, relaxed state and relieve occasional sleeplessness by positively impacting serotonin function.

FDA Disclaimer Statement

These statements have 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: Take two tablets daily or as directed by your healthcare practitioner. May be taken during the day or before bedtime.

Precautions

WARNING: Do not use if pregnant or lactating.

CAUTION: Not recommended for those under 18 years of age.

If taking antidepressant medication, particularly antidepressants such as MAO inhibitors or selective serotonin reuptake inhibitors (SSRIs), avoid use. If you have a medical condition, or are taking medication-including over-the-counter cold medicine, consult your healthcare practitioner before use.

Use with caution when driving or operating machinery, may cause drowsiness.

Keep out of the reach of children.

General Statements

Genetic Potential Through Nutrition

Support for Serotonin Function

LSM003H1

PROD. SOMN

0410200 5/12

Seals/Symbols

5-MTHF BODY-READY FOLATE

FDA Statement of Identity

Dietary Supplement

Formulation

Vegetarian

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

See for yourself

Somnolin by Metagenics label

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

Somnolin 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 Somnolin by Metagenics

These are the 5 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Tablet(s) Dosage formTablet Or Pill Servings per container15 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.

Vitamin B6

Interacts with
210 drugs
40 mg per serving Form: Pyridoxine Hydrochloride

Vitamin B6 (pyridoxine) is an essential water-soluble vitamin that your body needs for metabolism, brain function, and making red blood cells. It is b...

Vitamin B6 monograph & 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

Vitamin B12

Interacts with
20 drugs
500 mcg per serving Form: Methylcobalamin

Vitamin B12 (cobalamin) is an essential nutrient your body needs to make red blood cells, keep nerves healthy, and support DNA. Supplements are very h...

Vitamin B12 monograph & interactions

L-5-Hydroxytryptophan

Interacts with
398 drugs
200 mg per serving Form: Griffonia simplicifolia

5-HTP is a compound your body uses to make serotonin, and people take it as a supplement hoping to improve mood, sleep, and headaches. Some early rese...

L-5-Hydroxytryptophan monograph & interactions

Folate

400 mcg per serving Form: L-5-methyl tetrahydrofolate

Other (inactive) ingredients: Microcrystalline Cellulose, Cellulose, Stearic Acid, Croscarmellose Sodium, Silica. These complete the product’s ingredient list but are not active constituents.

Interaction report

Somnolin by Metagenics Drug Interactions

Want to check YOUR meds against Somnolin?

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
592Drugs
570 Moderate 22 Minor

Ingredients driving the most interactions

L-Theanine 565
L-5-Hydroxytryptophan 398
Vitamin B6 210
Vitamin B12 20

Individual Drug Interactions

The ingredients in Somnolin interact with 592 drugs. Click any drug to see the details.

4 of the 5 ingredients in Somnolin interact with drugs. Each result below shows which ingredient is responsible. L-Theanine L-5-Hydroxytryptophan Vitamin B6 Vitamin B12

Each ingredient & the kinds of drugs it affects

For each ingredient in Somnolin 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.

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

L-5-Hydroxytryptophan3 drug types · 398 drugs

Carbidopa (Lodosyn)

Combining 5-HTP and carbidopa can increase the risk of serotonergic side effects.
Carbidopa is sometimes used with 5-HTP to minimize peripheral 5-HTP metabolism and boost the amount that reaches the brain. However, this combination might also increase the risk of some side effects including hypomania, restlessness, rapid speech, anxiety, insomnia, and aggressiveness. Combining carbidopa and 5-HTP might also increase the risk of scleroderma-like skin changes due to elevated serotonin levels.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, concomitant use of 5-HTP with medications that cause sedation might have additive effects.
In clinical trials, 5-HTP has been associated with drowsiness and somnolence.

Likelihood Possible Evidence D
Serotonergic Drugs

Combining serotonergic drugs with 5-HTP might cause additive serotonergic effects.
5-HTP can increase serotonin levels and cause serotonergic effects. Theoretically, combining serotonergic drugs with 5-HTP might increase the risk of serotonergic side effects, including serotonin syndrome and cerebral vasoconstrictive disorders. However, serotonin syndrome with 5-HTP has not yet been reported in humans. Monitor patients for signs of serotonin syndrome and other serotonergic side effects if using 5-HTP with serotonergic drugs.

Likelihood Possible Evidence D
L-5-Hydroxytryptophan full monograph & interactions

Vitamin B65 drug types · 210 drugs

Amiodarone (Cordarone)

Theoretically, vitamin B6 might increase the photosensitivity caused by amiodarone.
Despite initial case reports suggesting that pyridoxine may have a protective effect against amiodarone-induced photosensitivity, preliminary clinical research suggests that pyridoxine may actually exacerbate this adverse effect.

Likelihood Possible Evidence B
Antihypertensive Drugs

Theoretically, vitamin B6 may have additive effects when used with antihypertensive drugs.
Research in hypertensive rats shows that vitamin B6 can decrease systolic blood pressure. Similarly, clinical research in patients with hypertension shows that taking high doses of vitamin B6 may reduce systolic and diastolic blood pressure, possibly by reducing plasma levels of epinephrine and norepinephrine.

Likelihood Possible Evidence B
Phenobarbital (Luminal)

High doses of vitamin B6 may reduce the levels and clinical effects of phenobarbital.
Preliminary clinical evidence suggests that vitamin B6 200 mg daily can reduce plasma levels of phenobarbital, possibly by increasing metabolism. It is not known whether lower doses have any effect. Advise people taking phenobarbital to avoid high doses of vitamin B6.

Likelihood Possible Evidence D
Phenytoin (Dilantin)

High doses of vitamin B6 may reduce the levels and clinical effects of phenytoin.
Preliminary clinical evidence suggests that vitamin B6 200 mg daily can reduce plasma levels of phenytoin, possibly by increasing metabolism. It is not known whether lower doses have any effect. Advise people taking phenytoin to avoid high doses of vitamin B6.

Likelihood Possible Evidence D
Levodopa

Vitamin B6 may increase the metabolism of levodopa when taken alone, but not when taken in conjunction with carbidopa.
Vitamin B6 (pyridoxine) enhances the metabolism of levodopa, reducing its clinical effects. However, this interaction does not occur when carbidopa is used concurrently with levodopa (Sinemet). Therefore, it is not likely to be a problem in most people.

Likelihood Unlikely Evidence D
Vitamin B6 full monograph & interactions

Vitamin B121 drug type · 20 drugs

Metformin (Glucophage)

Metformin, a common medication used to manage type 2 diabetes, has been associated with lower vitamin B12 levels in some individuals. Prolonged use of metformin can interfere with the absorption of B12 in the digestive system, potentially leading to a deficiency in this essential vitamin.

Likelihood Possible Evidence A
Vitamin B12 full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Somnolin, from the product label.

Metagenics

See all Metagenics products
Name
METAGENICS, INC. Makers of Professional Quality Supplements
Street Address
100 Ave. La Pata
City
San Clemente
State
CA
ZipCode
92673
Web Address
www.metagenics.com
Pharmacist Counseling Corner

Somnolin by Metagenics: Common Questions

Does Somnolin by Metagenics interact with any medications?
Yes. Based on its ingredients, Somnolin has a known interaction with 592 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Somnolin contains 5 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.
Can I take Somnolin if I'm pregnant or breastfeeding?
Vitamin B6 and B12 have safety data supporting use in pregnancy and breastfeeding at recommended amounts, but L-theanine and 5-HTP lack sufficient safety information for both stages — the safety data advise against them. Talk with your doctor or pharmacist about whether this product is right for you during pregnancy or while nursing.
What are the side effects I might experience?
Common side effects from individual ingredients include headache, drowsiness, nausea, diarrhea, and abdominal pain. Vitamin B6 at high doses can cause nerve damage over time. Rarely, 5-HTP has been associated with mood changes like agitation or hypomania. Most people tolerate these ingredients well short-term, but always report new or worsening symptoms to your provider.
Does this product actually help with sleep?
Our data doesn't include an effectiveness rating for Somnolin as a sleep aid product. We can tell you that L-5-hydroxytryptophan is possibly effective for depression and L-theanine is possibly effective for cognitive function, but whether the combination improves sleep specifically isn't established in our information.
Is it safe to take Somnolin long-term?
L-theanine's long-term safety isn't well studied. Vitamin B6 and 5-HTP can cause nerve damage or other issues at high doses or over extended periods. Talk with your pharmacist or doctor about how long it's appropriate for you to use this product.
What is 5-HTP and why is it in a sleep supplement?
L-5-hydroxytryptophan (5-HTP) is a compound your body uses to make serotonin, a brain chemical that affects mood, sleep, and relaxation. It's included because it may help with sleep and mood — though the evidence for sleep specifically isn't established in our data.
Will Somnolin interfere with my diabetes medication?
Vitamin B12 can interact with metformin (Glucophage), a common diabetes drug; metformin may lower your B12 levels over time. If you take metformin, check with your doctor or pharmacist before starting Somnolin to make sure your B12 levels stay healthy.

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.

Somnolin label
Go deeper

The Full Monographs Behind Somnolin’s Ingredients

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

Herb & supplement monograph

Vitamin B6

Interacts with 210 drugs

Vitamin B6 (pyridoxine) is an essential water-soluble vitamin that your body needs for metabolism, brain function, and making red blood cells. It is best known for helping with pregnancy-rel...

Read the full Vitamin B6 monograph → 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

Vitamin B12

Interacts with 20 drugs

Vitamin B12 (cobalamin) is an essential nutrient your body needs to make red blood cells, keep nerves healthy, and support DNA. Supplements are very helpful for people who are deficient — su...

Read the full Vitamin B12 monograph → Herb & supplement monograph

5-htp

Interacts with 398 drugs

5-HTP is a compound your body uses to make serotonin, and people take it as a supplement hoping to improve mood, sleep, and headaches. Some early research is promising, but the overall evide...

Read the full 5-htp monograph →
Sources

Sources & How We Checked

Somnolin'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 100 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.

Vitamin B6 32 references
  1. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  2. Yates AA, Schlicker SA, Suitor CW. Dietary reference intakes: The new basis for recommendations for calcium and related nutrients, B vitamins, and choline. J Am Diet Assoc 1998;98:699-706. PubMed
  3. Geerling BJ, Dagnelie PC, Badart-Smook A, et al. Diet as a risk factor for the development of ulcerative colitis. Am J Gastroenterol 2000;95:1008-13. PubMed
  4. South M. Neonatal seizures after pyridoxine use -- reply. Lancet 1999;354:2083. PubMed
  5. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline (2000). Washington, DC: National Academy Press, 2000. Available at: http://b
  6. Baxter P, Aicardi J. Neonatal seizures after pyridoxine use. Lancet 1999;354:2082-3. PubMed
  7. Bendich A, Cohen M. Vitamin B6 safety issues. Ann N Y Acad Sci 1990;585:321-30.
  8. Schaumburg H, Kaplan J, Windebank A. Sensory neuropathy from pyridoxine abuse. A new megavitamin syndrome. N Engl J Med 1983;309:445-8. PubMed
  9. Gordon N. Pyridoxine dependency: an update. Dev Med Child Neurol 1997;39:63-5. PubMed
  10. Lewis PJ. Pain in the hand and wrist. Pyridoxine supplements may help patients with carpal tunnel syndrome. BMJ 1995;310:1534. PubMed
  11. Kaufman G. Pyridoxine against amiodarone-induced photosensitivity (letter). Lancet 1984;1:51-2. PubMed
  12. Mulrow JP, Mulrow CD, McKenna WJ. Pyridoxine and amiodarone-induced photosensitivity. Ann Intern Med 1985;103:68-9. PubMed
  13. Kawada A, Kashima A, Shiraishi H, et al. Pyridoxine-induced photosensitivity and hypophosphatasia. Dermatology 2000;201:356-60.. PubMed
  14. Vasile A, Goldberg R, Kornberg B. Pyridoxine toxicity: report of a case. J Am Osteopath Assoc 1984;83:790-1. DOI
  15. Hansson O, Sillanpaa M. Pyridoxine and serum concentration of phenytoin and phenobarbitone. Lancet 1976;1:256. DOI
  16. Jansen T, Romiti R, Kreuter A, Altmeyer P. Rosacea fulminans triggered by high-dose vitamins B6 and B12. J Eur Acad Dermatol Venereol 2001;15:484-5..
  17. Chittumma P, Kaewkiattikun K, Wiriyasiriwach B. Comparison of the effectiveness of ginger and vitamin B6 for treatment of nausea and vomiting in early pregnancy: a randomized double-blind controlled trial. J Med Assoc Thai 2007;90:15-20.
  18. Hatzitolios, A., Iliadis, F., Katsiki, N., and Baltatzi, M. Is the anti-hypertensive effect of dietary supplements via aldehydes reduction evidence based? A systematic review. Clin Exp.Hypertens. 2008;30(7):628-639. PubMed
  19. Vasdev, S., Ford, C. A., Parai, S., Longerich, L., and Gadag, V. Dietary vitamin B6 supplementation attenuates hypertension in spontaneously hypertensive rats. Mol.Cell Biochem. 1999;200(1-2):155-162.
  20. de, Vogel S., Dindore, V., van, Engeland M., Goldbohm, R. A., van den Brandt, P. A., and Weijenberg, M. P. Dietary folate, methionine, riboflavin, and vitamin B-6 and risk of sporadic colorectal cancer. J Nutr 2008;138(12):2372-2378. PubMed
  21. Hagen, I., Nesheim, B. I., and Tuntland, T. No effect of vitamin B-6 against premenstrual tension. A controlled clinical study. Acta Obstet.Gynecol.Scand. 1985;64(8):667-670. PubMed
  22. Aybak, M., Sermet, A., Ayyildiz, M. O., and Karakilcik, A. Z. Effect of oral pyridoxine hydrochloride supplementation on arterial blood pressure in patients with essential hypertension. Arzneimittelforschung. 1995;45(12):1271-1273.
  23. Lal, K. J., Dakshinamurti, K., and Thliveris, J. The effect of vitamin B6 on the systolic blood pressure of rats in various animal models of hypertension. J Hypertens. 1996;14(3):355-363. PubMed
  24. Lauritzen CH, Reuter HD, Repges R, Bohnert K, and Schmidt U. Treatment of premenstrual tension syndrome with Vitex agnus castus. Controlled, double-blind study versus pyridoxine. Phytomed 1997;4(3):183-189. PubMed
  25. Fonseca VA, Lavery LA, Thethi TK, et al. Metanx in type 2 diabetes with peripheral neuropathy: A randomized trial. Am J Med 2013;126(2):141-9. PubMed
  26. Hankey GJ, Eikelboom JW, Yi Q, et al. Treatment with B vitamins and incidence of cancer in patients with previous stroke or transient ischemic attack: Results of a randomized placebo-controlled trial. Stroke 2012;43(6):1572-7. PubMed
  27. Hoyer-Kuhn H, Kohbrok S, Volland R, Franklin J, Hero B, Beck BB, Hoppe B. Vitamin B6 in primary hyperoxaluria I: first prospective trial after 40 years of practice. Clin J Am Soc Nephrol. 2014 Mar;9(3):468-77. PubMed
  28. Mahmoud A, Tabassum S, Al Enazi S, et al. Amelioration of levetiracetam-induced behavioral side effects by pyridoxine. A randomized double blind controlled study. Pediatr Neurol 2021;119:15-21. PubMed
  29. Gupta M, Gallante B, Bamberger JN, et al. Prospective randomized evaluation of idiopathic hyperoxaluria treatments. J Endourol 2021;35(12):1844-1851. PubMed
  30. Li H, Chen M, Liang S, et al. Excessive vitamin B6 during treatment is related to poor prognosis of patients with nasopharyngeal carcinoma: A U-shaped distribution suggests low dose supplement. Clin Nutr 2021;40(4):2293-2300. PubMed
  31. Tanigawa J, Nabatame S, Tominaga K, et al. High-dose pyridoxine treatment for inherited glycosylphosphatidylinositol deficiency. Brain Dev 2021;43(6):680-687. PubMed
  32. Committee on Practice Bulletins-Obstetrics. ACOG Practice Bulletin No. 189: Nausea And Vomiting Of Pregnancy. Obstet Gynecol. 2018;131(1):e15-e30. PubMed

See these in context on the Vitamin B6 monograph →

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
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5-htp 32 references
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