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Glutathione serum OEM/ODM manufacturing
Glutathione Serum · OEM/ODM
Glutathione is famous in the market thanks to advertising for oral and intravenous “skin whitening”, but cosmetics are topical only — and the topical route has far less data. It is a tripeptide of glutamate, cysteine and glycine carrying a thiol (–SH) group, and it acts as a natural antioxidant inside cells. The placebo-controlled topical trial cited by the ingredient article on our site used a 2% lotion of the oxidized form (GSSG) on one half of the face of 30 healthy women for 10 weeks, and a 2025 systematic review found only 5 topical trials and concluded that more randomized controlled trials are needed. That is why Butter-C writes a glutathione serum honestly: antioxidant, helps skin look brighter and more even-toned once tested on the finished product — with no comparison to intravenous infusion, which is a medical intervention with safety concerns. The hard part is in the factory: reduced GSH readily oxidizes to GSSG and a sulfur-containing ingredient can affect odor, so the raw-material form, chelating agent, airtight packaging and glutathione assays over time decide the quality. Glutathione is not named in ASEAN Annexes II, III or VI (06/2026 version); the ingredient is not in Butter-C's standing raw-material list, so it is sourced per order with a mandatory COA. Butter-C offers turnkey OEM/ODM, from formulation and testing to the labeled finished product and notification dossier.
Formula base
Glutathione in a low-oxygen water–glycol base
Glutathione is highly water-soluble, so it goes straight into the serum's water phase. What has to be settled up front is the correct raw-material form, how to limit oxidation and a concentration that can be justified in the safety assessment.
GSH or GSSG — two materials, two data sets
According to PubChem, reduced glutathione (GSH) is C10H17N3O6S, molecular weight 307.33, CAS 70-18-8, water solubility 292.5 mg/mL. The oxidized form (GSSG, glutathione disulfide) is two GSH molecules joined by a disulfide bridge, CAS 27025-41-8. The placebo-controlled topical trial by Watanabe 2014 used GSSG; the authors also note that before their study the effect of GSSG on pigmentation was unclear, whereas GSH was thought to act through tyrosinase inhibition. Data for one form are not used for the other when writing claims.
Sourced per order, COA mandatory
Glutathione is not in Butter-C's standing raw-material list. The COA must state the form (GSH or GSSG), CAS, purity, appearance and manufacturing date; the INCI on the raw-material sheet and on the label follows the name the supplier declares for that form. How the raw material is made (fermentation or synthesis) comes from the supplier's file — we have no verified source on this point.
Concentrations used in studies
GSSG 2% in a lotion (Watanabe 2014); topical glutathione at 0.1%, 0.5% and 2% in the studies reviewed, with 0.5% significantly more effective than 0.1% and placebo (Sarkar 2025). The level in the serum is set from the supplier's TDS, a stability study with assays and tolerance testing on the finished product; study results do not carry over automatically to another formula.
Humectant base, chelation, buffer and preservation
Glycerin, Propanediol, Sodium Hyaluronate and Panthenol make a light, moist base; Hydroxyethylcellulose adds slight body when needed; Disodium EDTA chelates metal ions; Sodium Citrate and Citric Acid buffer the pH — the pH range follows the TDS and is confirmed by a stability study with glutathione assays; Phenoxyethanol (max 1.0% — ASEAN Annex VI, Ref 29) with Ethylhexylglycerin.
Key technical points
Oxidation, odor, route of use and regulation
The general brightening-serum base is on our generic page; the four points below are about glutathione itself.
Unstable and poorly penetrating — assay it, don't just look at it
Glutathione is described as unstable and limited in its penetration through the stratum corneum (Liu 2024; Cui 2024). GSH and GSSG are a redox pair: the reduced form in solution can gradually turn into the disulfide, at a rate that depends on oxygen, pH and metal ions (general thiol chemistry). The stability plan therefore assays GSH (and GSSG if needed) at each time point; we reduce air entrainment during mixing and headspace in the bottle, use a chelating agent and airtight packaging.
Sulfur odor and addition temperature per the TDS
A sulfur-containing ingredient can affect the odor of the finished product; its intensity, the optimal pH range and the addition temperature come from the supplier's TDS and are confirmed by sensory evaluation over time. We do not mask odor with heavy fragrance before the cause is known — an odor that grows stronger may mean the ingredient is changing and needs to be assayed again.
Topical, oral and intravenous are three different things
Topical use is within the cosmetic scope. Oral use is systemic: oral trials reported lower melanin index than placebo according to the Sarkar 2025 review, but those are not data for a topical product. Intravenous infusion is a medical intervention: there was only one placebo-controlled study, and the review authors concluded it is contraindicated because of lack of efficacy and side effects (Sarkar 2025); a 2026 review raises concerns about hepatotoxicity, hypersensitivity and possible renal and endocrine effects (Aloraini 2026). Butter-C does not suggest, or compare the serum with, intravenous infusion.
Regulatory: not named in the ASEAN annexes
Glutathione (CAS 70-18-8) and glutathione disulfide (CAS 27025-41-8) are not named in ASEAN Annexes II, III or VI (06/2026 version) — Butter-C has re-checked the annex files; there is therefore no specific concentration limit, and the safety of the chosen level is demonstrated in the Product Information File (PIF). Annex III Ref A7 restricts “Thioacids and their derivatives” with the condition “Not for use around the eye area”; glutathione carries a thiol group but is not a thioacid and is not named — this reading needs regulatory confirmation, so the serum label advises avoiding the eye area. We have not been able to read a CIR report or an SCCS opinion specific to glutathione.
Three formulation directions
The same glutathione, three ways to combine it
Single-active glutathione serum
Glutathione in a humectant water–glycol base (Glycerin, Propanediol, Sodium Hyaluronate, Panthenol), Disodium EDTA, a citrate buffer and preservatives. A short ingredient list with the story focused on one active; the key parameters are the glutathione assay and odor across the stability time points.
Glutathione – niacinamide serum
Adds niacinamide at 2–5%, the range with human data on even skin tone according to our niacinamide article. The glutathione article on our site notes that the two are often used together, but we have not found a study of this exact pair — stability, color, odor and tolerance must be tested on the formula; one more assay is added.
Glutathione – tranexamic acid serum
Adds tranexamic acid within ASEAN Annex III Ref A10 (skin products, max 3.0%, not to be used in products intended to contact mucous membranes) — a pairing suggested by the glutathione article. There is no study of this exact pair; the label advises avoiding the lips and eyes; stability and tolerance are tested separately.
How it differs from our other pages
The brightening serum is a generic page choosing among several active groups; the tranexamic acid – alpha-arbutin serum and the niacinamide & zinc serum feature actives with more human data; the brightening body cream uses glutathione as one ingredient in a body cream base. This page is for a facial serum featuring glutathione, built around the raw-material form, stability and the evidence limits of this ingredient.
Parameters we monitor
What the R&D lab measures on every sample
These are the parameters Butter-C tracks during formula development and scale-up. Specific limits are agreed with you on the approved sample and then written into the product's in-house specification.
- Raw material COA
- Glutathione form (GSH or GSSG), CAS, purity, appearance, manufacturing date and the supplier's storage conditions; niacinamide (if used): free nicotinic acid.
- Glutathione content
- Assayed by a suitable method at the start and after each stability time point; with GSH, the share converted to GSSG is tracked when needed; any figure on the label must match the results to the end of the shelf life.
- Appearance, odor & color
- Compared with the reference sample across stability time points; a growing sulfur odor or yellowing signals that the content should be assayed again.
- pH
- Measured directly at 25°C; the pH range follows the TDS and is confirmed by a stability study with glutathione assays; pH drift is tracked.
- Stability
- Accelerated aging, freeze–thaw cycling and real-time monitoring in the final pack; remaining content and odor are compared — the basis for shelf life and storage conditions.
- In-use simulation
- Pumping or opening on a schedule, then re-measuring content and odor — the basis for the period-after-opening.
- Microbiology & preservative challenge
- Tested at a GLP / ISO 17025-accredited laboratory; preservative efficacy (challenge) test to ISO 11930 on the final formula.
- On-skin assessment
- Tolerance testing on the finished product; to claim “skin looks brighter and more even-toned”, measure it on volunteers using the finished product itself (colorimeter, standardized photos).
Claims
Claims matched to the evidence for topical glutathione
Watanabe 2014: randomized, double-blind, matched-pair half-face comparison in 30 healthy women aged 30–50, applying GSSG 2% lotion to one side and placebo lotion to the other twice daily for 10 weeks; the melanin index was significantly lower than with placebo from the early weeks to the end of the study, the second half showed higher stratum corneum moisture and smoother skin, with no marked adverse effects; three of the four authors work for a raw-material manufacturer. Wahab 2021: randomized, double-blind, 46 people, each applying glutathione to one side of the face and placebo to the other, plus oral glutathione or placebo, for 8 weeks; the topical + oral combination differed significantly from placebo — the oral part is systemic, and the abstract does not state the topical concentration. Khanna 2025 (systematic review of topical trials only) found just 5 trials, noted that glutathione may improve hyperpigmentation, that safety data are limited, and concluded that more randomized controlled trials are needed. The proposed mechanisms (tyrosinase inhibition, regulation of oxidative stress, shifting synthesis toward pheomelanin) may not translate into clinically meaningful outcomes (Aloraini 2026). Level of evidence for topical glutathione: limited.
Contains glutathione — an antioxidant (cosmetic level)
Basis: glutathione is a major antioxidant in cells, protecting protein thiol groups (Watanabe 2014); state the form (GSH or GSSG) correctly and state the % only when it can be assayed at the end of shelf life. Instead of: sun protection, replaces sunscreen, “pure glutathione”.
Helps skin look brighter and more even-toned (to be tested on the finished product)
Basis: the topical data above and results measured on the serum itself; always paired with a sunscreen recommendation. GSSG data are not used to advertise a GSH product, or the other way round. Instead of: skin whitening, instant tone-up, erases melasma, fades dark spots, fast whitening.
No comparison with oral or intravenous glutathione
Oral use is systemic and intravenous infusion is a medical intervention with safety concerns (Sarkar 2025; Aloraini 2026); results from these routes do not apply to a topical product. No images of needles or drips on packaging or promotional material. Instead of: “works like a whitening drip”, “replaces glutathione injections”, “oral glutathione in a cream”.
Use sunscreen during the day
UV is a trigger for pigment production, and sun protection is the foundation of any even-tone routine (glutathione article on our site). A 2016 review of injected glutathione also raised the hypothesis that switching from brown to red melanin might increase the risk of sun-induced skin cancer in people previously protected by their pigment (Davids 2016) — a hypothesis raised in the context of systemic use, with no data for topical products. Instead of: prevents tanning, use instead of sunscreen.
Label reminders
Avoid the eye area (pending regulatory confirmation of the Annex III Ref A7 reading); patch test on a small area first, since the finished product always contains many ingredients; stop if redness or itching persists; close tightly after use; pregnant and breastfeeding women: data for topical products are insufficient, ask a doctor. Instead of: non-irritating, safe for expectant mothers, suits every skin.
Manufacturing specifications
Capabilities
- Texture
- Clear water–glycol serum or lightly thickened serum-gel; colorless to pale yellow depending on the formula.
- Packaging format
- Light-protective airless pump bottle or small dark glass bottle. Volume agreed when choosing packaging.
- Raw material sourcing
- Glutathione sourced per order with a mandatory COA; niacinamide and tranexamic acid according to the chosen direction.
- Minimum order quantity
- Agreed per order — depends on the formula direction, packaging format and raw-material lot.
- Testing
- Tested at a GLP / ISO 17025-accredited laboratory, with glutathione assays according to the stability plan; certificates of analysis delivered with every batch.
- Documentation
- Product Information File (PIF) and cosmetic product notification dossier prepared by Butter-C, with the raw-material COA, stability data and the safety assessment for the chosen glutathione level.
- Packaging
- Label design, printing and packing run in parallel with formulation; the label states the glutathione form, recommends daytime sunscreen and avoiding the eye area.
Suggested product concept
Glutathione – niacinamide serum, 30 ml airless bottle
One product concept to help you picture the result; not a ready-made product for sale. The actual formula is built around your brand's positioning and price range.
Glutathione as the featured ingredient
Form stated on the COA and label; level per the supplier's TDS, finalized after a stability study with assays and tolerance testing.
Niacinamide
2–5% according to our niacinamide article; free nicotinic acid checked on the COA.
Fragrance-free humectant base
Glycerin, Propanediol, Sodium Hyaluronate, Panthenol; Disodium EDTA chelates metal ions — its effect on retained content is confirmed by stability testing.
Light-protective airless bottle
Limits air contact throughout use; the label lists the full INCI, recommends daytime sunscreen and avoiding the eye area; claims stop at “helps skin look brighter and more even-toned” after testing on the finished product.
Customization options
What you can specify
The same product type can serve very different customers. Tell us your requirements in the areas below and our pharmacists will build the matching formula.
Raw-material form
GSH (reduced) or GSSG (the form tested topically by Watanabe 2014) — INCI, COA and promotional wording follow the chosen form; a glutathione amino acid precursor blend is a different ingredient with different claims.
Concentration
Within the range of the reviewed studies (0.1–2%), set from the TDS, a stability study with assays and tolerance testing on the finished product.
Supporting actives
Niacinamide, tranexamic acid (max 3.0%, not for products contacting mucous membranes — Annex III Ref A10), Sodium Hyaluronate, Panthenol; each combination needs its own stability and tolerance testing.
Ingredient preferences
Fragrance-free, alcohol-free — please state this at the start so the ingredient's odor can be assessed and a suitable preservative system chosen.
Packaging
Light-protective airless bottle or small dark glass dropper bottle — decides air exposure after opening and the period-after-opening.
Companion products
A daytime sunscreen in the same line to sell as a set, helping users follow the directions.
Further reading
Related topics
Glutathione in cosmetics
Topical evidence, how it differs from oral and injected use, stability, safety and ASEAN regulation (in Vietnamese).
Managing skin pigmentation
Why sun protection is the foundation of every even-tone product (in Vietnamese).
Niacinamide in cosmetics
A supporting active with human data on even skin tone (in Vietnamese).
Brightening serum OEM/ODM
Generic page: choosing active groups, base formula and packaging for a brightening line.
Tranexamic acid & alpha-arbutin serum OEM/ODM
Another direction: two water-soluble actives with their own limits and data.
Niacinamide & zinc serum OEM/ODM
Another direction: niacinamide 2–5% for oily and combination skin.
How we work
From idea to finished batch
Eight steps and three milestones signed off by both sides: approved sample, notification number, finished batch. Step-by-step details →
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