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Dietary supplement

Glycine 1000 mg Ingredients & Drug Interactions

by NOW

Capsule Category: Amino Acid/protein
Most serious interaction: Moderate
The interaction bottom line Most serious interaction: Moderate

Glycine 1000 mg is a dietary supplement by NOW with 1 active ingredient. Its ingredients are commonly taken for sleep quality and insomnia, relaxation, cognitive function.Based on those ingredients, 1 medication has a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Glycine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of Glycine 1000 mg by NOW

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

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 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains one active ingredient: glycine, an amino acid your body makes naturally and uses in protein synthesis and nervous system function. The capsule itself is filled with inactive ingredients — hypromellose, hydroxypropyl cellulose, stearic acid, and silicon dioxide — which are standard tablet and capsule materials.

Does it work?

Not established
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
Not established

The graded evidence we hold for these ingredients covers different conditions than the ones this product is marketed for, so there's no established rating for its stated use — see Glycine's own graded uses on its monograph.

Why this rating?
  • The label markets this product for: Neurotransmitter and nervous system support, sleep.
  • We looked for evidence on: Insomnia, Cognitive function, Relaxation, Sleep quality.
  • The closest evidence on file: Glycine is rated "Insufficient Reliable Evidence To Rate" for Cognitive function (Natural Medicines).
  • Also on file: Glycine is rated "Insufficient Reliable Evidence To Rate" for Insomnia.

Glycine is rated possibly effective for schizophrenia based on available evidence. For other uses listed — 3-phosphoglycerate dehydrogenase (3-PGDH) deficiency, ADHD, benign prostatic hyperplasia (BPH), and cystic fibrosis — the evidence we hold is insufficient to rate it either way.

The evidence, ingredient by ingredient Glycine

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 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Glycine is generally well tolerated at typical doses, though long-term safety data are limited. Mild sedation, irritability, insomnia, fatigue, memory problems, headache, and sensory changes have been reported rarely, as have soft stools, nausea, vomiting, upper stomach discomfort, and dry mouth — these resolve quickly if you stop taking it.

The data we have on glycine during pregnancy and breastfeeding is insufficient to know whether it's safe; talk with your doctor or pharmacist for personalized guidance before using it in either situation.

Side effects, ingredient by ingredient Glycine

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?
  • 1 of the 1 matched ingredient can interact with medications — Glycine.
  • The most serious interaction on file is rated Moderate.
  • For scale: 1 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.

If you take clozapine (Clozaril) for schizophrenia, double-check with your pharmacist before adding this supplement — glycine may reduce its effectiveness. For all other medications, no interactions are documented in our data for glycine.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no established evidence rating for its marketed use. Moderate medication interactions have been identified, and safety information is well characterized.

Glycine may help with schizophrenia symptoms, though the evidence is limited. If you take clozapine, check with your pharmacist first — this supplement may reduce how well it works.

Generally well tolerated, but long-term safety hasn't been fully studied.

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

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Aug 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 Glycine 1000 mg, straight from the product label.

Brand NOW
Barcode (UPC) 733739001078
Net contents 100 Veg Capsule(s)
Market status On market
Date entered into DSLD Aug 22, 2024
DSLD ID 314375
Product type Amino Acid/protein
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Kosher, 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 Glycine 1000 mg by NOW, 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:
1 Veg Capsule(s)
Maximum serving Sizes:
3 Veg Capsule(s)
Servings per container
33
UPC/BARCODE
733739001078
IngredientAmount% DV
Glycine3 Gram(s)--

Other ingredients: Hypromellose, Hydroxypropyl Cellulose, Stearic Acid, Silicon Dioxide

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.
Suggested/Recommended/Usage/Directions

Suggested Usage: Take 1-3 capsules daily, preferably on an empty stomach.

Formula

Glycine is the smallest and simplest amino acid, making it versatile for use in a wide range of functions. Glycine is necessary for the production of glutathione, DNA, creatine, bile, hemoglobin, and most proteins. It also helps to promote glycogen storage, thereby making glucose readily available for energy production. Glycine also functions as a calming neurotransmitter in the brain, where it facilitates nerve impulses and is important for the maintenance of healthy sleep patterns.

Triangle K (Kosher)

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.

Precautions

Caution: For adults only.

Consult physician if pregnant/nursing, taking medication, or have a medical condition.

Keep out of reach of children.

Not manufactured with wheat, gluten, soy, corn, milk, egg, fish, shellfish or tree nut ingredients. Produced in a GMP facility that processes other ingredients containing these allergens.

Formulation

Natural color variation may occur in this product.

Neurotransmitter support Pharmaceutical grade, free-form Promotes restful sleep Nervous system support

Non-GMO

Vegetarian/Vegan

Not manufactured with wheat, gluten, soy, corn, milk, egg, fish, shellfish or tree nut ingredients.

FDA Statement of Identity

A Dietary Supplement

Seals/Symbols

Triangle K (Kosher)

GMP Quality Assured

General Statements

Amino Acids Family owned since 1968.

Storage

Store in a cool, dry place after opening.

See for yourself

Glycine 1000 mg by NOW label

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

What’s inside

The Ingredients in Glycine 1000 mg by NOW

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size1 Veg Capsule(s) Dosage formCapsule Servings per container33 Amounts shown are per serving.

Glycine

Interacts with
1 drug
3 Gram(s) per serving

Glycine is a non-essential amino acid your body makes on its own and that also appears in protein-rich foods. It is most studied for improving sleep q...

Glycine monograph & interactions

Other (inactive) ingredients: Hypromellose, Hydroxypropyl Cellulose, Stearic Acid, Silicon Dioxide. These complete the product’s ingredient list but are not active constituents.

Interaction report

Glycine 1000 mg by NOW Drug Interactions

Want to check YOUR meds against Glycine 1000 mg?

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
1Drugs
1 Moderate

Ingredients driving the most interactions

Each ingredient & the kinds of drugs it affects

For each ingredient in Glycine 1000 mg with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

Glycine1 drug type · 1 drug

Clozapine (Clozaril)

Theoretically, glycine might decrease the effectiveness of clozapine.
One small clinical study in patients with schizophrenia shows that adding glycine to clozapine therapy worsens symptoms of schizophrenia when compared with clozapine alone. The mechanism of this interaction is unclear.

Likelihood Probable Evidence B
The maker

Brand information

Manufacturer and brand details for Glycine 1000 mg, from the product label.

NOW

See all NOW products
Name
NOW FOODS
Street Address
395 S. Glen Ellyn Rd.
City
Bloomingdale
State
IL
ZipCode
60108
Web Address
nowfoods.com
Pharmacist Counseling Corner

Glycine 1000 mg by NOW: Common Questions

Does Glycine 1000 mg by NOW interact with any medications?
Yes. Based on its ingredients, Glycine 1000 mg has a known interaction with 1 medication. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Glycine 1000 mg contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism 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.
Does glycine actually work for schizophrenia?
It's rated possibly effective based on available evidence, but the research is still limited. Talk with your doctor about whether it might be right for your situation — especially if you're already on clozapine, since this supplement may interfere with that drug.
What side effects might I get from taking this?
Most people tolerate it well, but mild sedation, irritability, insomnia, fatigue, headache, nausea, soft stools, and dry mouth have been reported rarely. These symptoms clear up quickly if you stop taking it.
Is it safe to take glycine while pregnant or breastfeeding?
There isn't enough reliable safety data to know either way. Talk with your doctor or pharmacist before using it if you're pregnant or breastfeeding — they can give you personalized advice based on your situation.
Why are there so few interactions with this product?
This is a single-ingredient supplement — it's just glycine. That means there's only one ingredient to check against medications. The more ingredients a supplement has, the more potential interactions it may have.

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

Not sure if Glycine 1000 mg is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.

Glycine 1000 mg label
Go deeper

The Full Monographs Behind Glycine 1000 mg’s Ingredients

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

Sources

Sources & How We Checked

Glycine 1000 mg'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 5 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.

Glycine 5 references
  1. Heresco-Levy U, Javitt DC, Ermilov M, et al. Efficacy of high-dose glycine in the treatment of enduring negative symptoms of schizophrenia. Arch Gen Psychiatry 1999;56:29-36.. PubMed
  2. Potkin SG, Jin Y, Bunney BG, Costa J, Gulasekaram B. Effect of clozapine and adjunctive high-dose glycine in treatment-resistant schizophrenia. Am J Psychiatry 1999;156:145-7.. PubMed
  3. Gusev EI, Skvortsova VI, Dambinova SA, et al. Neuroprotective effects of glycine for therapy of acute ischaemic stroke. Cerebrovasc Dis 2000;10:49-60. PubMed
  4. Inagawa K, Kawai N, Ono K, Sukegawa E, Tsubuku S, Takahashi M. Assessment of acute adverse effects of glycine ingestion at a high dose in human volunteers. Seikatsu Eisei. 2006; 50:27-32.
  5. Woods SW, Walsh BC, Hawkins KA, Miller TJ, Saksa JR, D'Souza DC, Pearlson GD, Javitt DC, McGlashan TH, Krystal JH. Glycine treatment of the risk syndrome for psychosis: report of two pilot studies. Eur Neuropsychopharmacol. 2013 Aug;23(8):931-40. PubMed

See these in context on the Glycine monograph →

Parts of this content are provided by the Therapeutic Research Center, LLC.

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.

© 2021 Therapeutic Research Center, LLC

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