Free Form L-Glycine Unflavored Ingredients & Drug Interactions
by Muscle Feast
What is this page for?
First and foremost: checking Free Form L-Glycine Unflavored 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
Free Form L-Glycine Unflavored is a dietary supplement by Muscle Feast 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 L-Glycine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against Free Form L-Glycine Unflavored by Muscle Feast
Ask about any prescription or over-the-counter medication and we check it for interactions with Free Form L-Glycine Unflavored by Muscle Feast — and tell you which ingredient is responsible.
AI summaries are generated from our interaction database for education only — always confirm with your pharmacist. How we use AI
Ask the Pharmacist
A licensed pharmacist will answer your question by email — free, usually within 24 hours.
Got it — thank you!
A licensed pharmacist will answer within 24 hours. Keep an eye on your email (worth checking spam, just in case).
HelloPharmacist Scorecard of Free Form L-Glycine Unflavored by Muscle Feast
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.
What’s inside
Full disclosure
This product is pure L-glycine — a single amino acid, the building block of protein. There are no inactive ingredients or fillers listed.
Does it work?
Not established
The evidence is clearest for schizophrenia, where glycine is rated possibly effective as an add-on therapy. For other uses — low 3-phosphoglycerate dehydrogenase (3-PGDH) deficiency, attention deficit-hyperactivity disorder (ADHD), benign prostatic hyperplasia (BPH), and cystic fibrosis — we don't have enough reliable evidence to rate it.
If you're considering glycine for any of those conditions, your doctor can help weigh what little evidence exists against your individual situation.
How safe is it?
Well-documented data
L-glycine is generally well tolerated at typical doses, but long-term safety data are limited, so if you plan to use it long-term, check in with your doctor. A small number of trial participants reported mild sedation, irritability, insomnia, fatigue, memory impairment, headache, sensory changes, soft stools, nausea, vomiting, upper stomach discomfort, or dry mouth — these are rare and usually clear quickly if you stop taking it.
Data on safety during pregnancy and breastfeeding aren't on file, so talk with your doctor or pharmacist about whether to use it if you're pregnant, trying to conceive, or nursing.
Meds to double-check
Moderate interaction found
The main medication to watch for is clozapine (Clozaril), an antipsychotic — glycine may worsen schizophrenia symptoms if you're already on it. If you take clozapine or any other regular medication, confirm with your doctor or pharmacist before you start this supplement.
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.
Muscle Feast L-Glycine is a straightforward single-ingredient supplement that's generally well tolerated. If you take clozapine or any other prescription medication, check with your doctor or pharmacist first — the interaction with clozapine is the main concern.
For most other uses, evidence is still being built, so it's worth discussing your reason for taking it with your healthcare provider.
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 Apr 11, 2022.
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
General information
Key facts about Free Form L-Glycine Unflavored, straight from the product label.
| Brand | Muscle Feast |
|---|---|
| Net contents | 7 Ounce(s); 200 Gram(s) |
| Market status | On market |
| Date entered into DSLD | Apr 11, 2022 |
| DSLD ID | 262376 |
| Product type | Amino Acid/protein |
| Supplement form | Powder |
| Dietary claims / uses | Nutrient, All Other, Structure/Function |
| Intended target group(s) | Vegan, Vegetarian, Adult (18 - 50 Years), Women (not pregnant or lactating) |
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 Free Form L-Glycine Unflavored by Muscle Feast, sourced from the NIH Dietary Supplement Label Database.
Tap any ingredient to jump to its full detail below.
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.
Formula
Muscle Feast L-Glycine is an amino acid that plays a critical role in the body's production of glutathione, creatine, and collagen. Individuals that supplement with glycine may see many benefits, including protection against muscle loss, increased brain function, protection of the liver and heart, and it may even improve sleep quality.
Suggested/Recommended/Usage/Directions
Suggested use: As an adult dietary supplement, take one 5cc serving (4.3g) one to three times daily with water or fruit juice. Mix 1 serving (4.3g) with water or fruit juice up to 3 times a day.
Formulation
Non-GMO
Certified Vegan AVA American Vegetarian Association
Heart health Brain function Improved sleep
Seals/Symbols
Made in Our GMP Compliant Facility Made in an FDA Registered Facility Certified Vegan AVA American Vegetarian Association
General Statements
SDVOSB Service Distributed Veteran Owned Small Business 46 Servings
Ohio Family Owned Business
FDA Statement of Identity
Dietary Supplement
Storage
Keep tightly closed in a cool, dry place away from sunlight.
Precautions
Keep out of reach of children.
Do not exceed the recommended dose. Consult your physician before using this product.
Do not use this product if you are pregnant or nursing. Do not use this product if you are taking any prescription medication.
Do not use this product if you are under the age of 18.
Warning: This product is manufactured in a GMP compliant plant that processes milk.
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.
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
Free Form L-Glycine Unflavored by Muscle Feast label
The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.
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)The Ingredients in Free Form L-Glycine Unflavored by Muscle Feast
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size4.3 Gram(s) Dosage formPowder Servings per container46 Amounts shown are per serving.
L-Glycine
Interacts with1 drug
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...
L-Glycine monograph & interactionsOther (inactive) ingredients: None. These complete the product’s ingredient list but are not active constituents.
Free Form L-Glycine Unflavored by Muscle Feast Drug Interactions
HelloPharmacist Interaction Report
Muscle Feast Free Form L-Glycine Unflavored contains one active ingredient — L-glycine — which has a documented interaction with one medication.
If you take clozapine (Clozaril), an antipsychotic for schizophrenia, adding glycine to your regimen may worsen schizophrenia symptoms. A small clinical trial showed this effect, though the exact reason isn't yet clear.
Read the full breakdown — every affected drug type, severity by severity
Although only one medication interaction is documented in our data, if you're on any prescription drugs, run them through the interaction checker below before you start. If clozapine or any other antipsychotic is part of your routine, talk with your doctor or pharmacist before adding this supplement.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against Free Form L-Glycine Unflavored?
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 checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in Free Form L-Glycine Unflavored interact with 1 drug. Click any drug to see the details.
1 of the 1 ingredient in Free Form L-Glycine Unflavored interact with drugs. Each result below shows which ingredient is responsible. L-Glycine
ClozapineClozaril, Versacloz
How Clozapine interacts with Free Form L-Glycine Unflavored — through 1 ingredient. Tap an ingredient for the detail:
L-glycineClozapine (clozaril) Moderate
Interaction Summary
Theoretically, glycine might decrease the effectiveness of clozapine.
Read the full L-glycine + Clozapine interactionEach ingredient & the kinds of drugs it affects
For each ingredient in Free Form L-Glycine Unflavored 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.
L-Glycine
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.
Brand information
Manufacturer and brand details for Free Form L-Glycine Unflavored, from the product label.
Muscle Feast
See all Muscle Feast products- Name
- Muscle Feast
- Street Address
- 1320 Boston Road
- City
- Nashport
- State
- OH
- ZipCode
- 43830
- Phone Number
- (888) 734-3634
- Web Address
- www.musclefeast.com
Free Form L-Glycine Unflavored by Muscle Feast: Common Questions
Does Free Form L-Glycine Unflavored by Muscle Feast interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Can I take this if I'm on clozapine for schizophrenia?
Does L-glycine actually help with schizophrenia?
Is it safe to use long-term?
What side effects might I notice?
Is it safe during pregnancy or breastfeeding?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if Free Form L-Glycine Unflavored is safe with your meds?
Our pharmacists answer your medication & supplement questions — free.
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.
The Full Monographs Behind Free Form L-Glycine Unflavored’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Sources & How We Checked
Free Form L-Glycine Unflavored'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.
- NIH Dietary Supplement Label Database (DSLD) — The official product label on file for this supplement.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference behind the ingredient interaction data.
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
- 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
- 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
- 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
- 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.
- 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
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