Zinc PCA: what the evidence shows for oily skin, blemishes and scalp
Zinc PCA is a staple of oil-control and blemish-care products. CSL formulation scientists found no trial of it on its own; the human data come from multi-active products, so claims need to stay modest.
By CSL Formulation team · Evidence checked by CSL scientists
At a glance
- What it is
- The zinc salt of pyrrolidone carboxylic acid (PCA), a natural part of the skin's moisturising factor
- Main benefits
- Claimed: less visible shine and oiliness; a supporting role in blemish and oily-scalp formulas
- Levels tested in trials
- 1% in the one vehicle-controlled study found (with 4% niacinamide and 3% of a vitamin B6 derivative); usually not disclosed
- Time to results
- 2 to 6 weeks in the multi-active studies found
- Watch for
- No trial of zinc PCA alone; sebum results are inconsistent; claims should rest on tests of the finished product
01What is it?
Zinc PCA combines zinc with PCA, a moisture-binding molecule that occurs naturally in the skin. It is used in toners, serums, cleansers, moisturisers and scalp products for oily and blemish-prone skin. It is almost always used alongside other actives, such as niacinamide or salicylic acid.
02What it does
Zinc has antibacterial and anti-inflammatory effects and may reduce sebum, according to reviews of zinc in acne; PCA helps hold moisture. The expected visible benefit is less shine and calmer-looking skin. In the human studies found, zinc PCA's own share of any benefit cannot be separated from the other ingredients, and measured sebum did not consistently fall.
03The evidence
Studies below were checked against the publisher, DOI or journal record on 26 Sep 2026. We list design and size so you can judge the strength of each result.
| Study | Design | Who and how long | What it found |
|---|---|---|---|
| Armanious et al. 2026, Journal of Cosmetic Dermatology (Wiley) Source | Open-label study, no control group; multi-active regimen | 20 adults with acne-prone skin, 30 days, eight-product regimen with zinc PCA, salicylic acid and niacinamide (levels not disclosed) | Sebum fell 9.1%, inflammatory spots 23% and non-inflammatory spots 32%, with less visible pores. Zinc PCA's own effect cannot be separated from the other ingredients. |
| Ge et al. 2025, Journal of Cosmetic Dermatology (Wiley) Source | Prospective cohort study, no control group; multi-active scalp products | 20 adults with moderate to severe scalp seborrhoeic dermatitis, 4 weeks plus 12-week maintenance, pre-gel and cleanser with salicylic acid, piroctone olamine and zinc PCA (levels not disclosed) | At 4 weeks, dandruff scores fell from 2.45 to 1.10 and greasiness from 2.60 to 1.40; no adverse events. Piroctone olamine and salicylic acid are likely major contributors. |
| Patel et al. 2024, Cureus (Springer Nature) Source | Open-label, single-arm study; manufacturer-funded; multi-active regimen | 29 adults with mild to moderate acne completed 15 days; cleanser with zinc PCA and azelaic acid plus a niacinamide serum (levels not disclosed) | Porphyrins fell 39.9% and 79% were nearly clear by day 15, but measured sebum rose 75.8% (Sebumeter), so the study gives no support for an oil-control claim. |
| Zou et al. 2023, Frontiers in Medicine (Frontiers) Source | Narrative review of zinc and skin disorders | Oral and topical zinc across skin conditions, including acne | Zinc has antibacterial and anti-inflammatory effects and may reduce sebum, but doses vary widely and larger double-blind controlled studies are needed. |
| Andrade et al. 2018, Biomedical and Biopharmaceutical Research Source | Vehicle-controlled study (randomisation and blinding not described); multi-active cream | 15 women aged 18–30 with mild acne, 6 weeks, cream gel with 1% zinc PCA, 4% niacinamide and 3% pyridoxine tris-hexyldecanoate | Inflammatory lesions fell 60% with the full formula, with lower porphyrin fluorescence; sebum did not change significantly. |
| Brandt 2013, Journal of Drugs in Dermatology Source | Systematic review (SORT grading) | Published studies of oral and topical zinc in acne (zinc salts in general, not zinc PCA specifically) | Topical zinc earned only a grade B: inconsistent or limited-quality evidence, although zinc may reduce sebum and has antibacterial and anti-inflammatory effects. |
Zinc PCA is a reasonable, well-tolerated supporting ingredient in oil-control, blemish and scalp formulas, but no trial has tested it on its own, and measured sebum fell in only one of the studies found. Keep claims to the finished product and to what was measured, for example “helps reduce the look of shine” or “helps keep skin looking clearer”, and do not present zinc PCA as a proven sebum-reducer by itself.
04How CSL formulation scientists use it
- Zinc PCA is water-soluble and easy to add to toners, gels, emulsions and shampoos; the one disclosed trial level was 1%. CSL formulation scientists check compatibility with thickeners and chelating agents, which can bind zinc.
- It is usually combined with better-evidenced actives such as niacinamide, salicylic acid or, on the scalp, piroctone olamine, so claims should reflect the whole formula.
- Sebum and shine claims should be supported by instrumental testing (for example Sebumeter readings) on the finished product, because published sebum results are inconsistent.
- It was well tolerated in all the studies found, which makes it a practical choice for leave-on and rinse-off products for oily skin and scalp.
05Regulatory and claims
No specific restriction for zinc PCA was confirmed during this review. CSL regulatory specialists confirm the status in each target market, including any rules on zinc compounds, and keep claims cosmetic: “helps reduce the look of shine” or “helps reduce visible flakes”, not “treats acne” or “treats seborrhoeic dermatitis”.
06Questions brands ask
Does zinc PCA reduce oil on its own?
That has not been shown. No trial of zinc PCA alone was found, and in the multi-active studies sebum fell in one, did not change in another and rose in a third.
Does zinc PCA help with dandruff or an oily scalp?
A small uncontrolled 2025 study of scalp products with zinc PCA, salicylic acid and piroctone olamine found less flaking and greasiness over 4 weeks. The anti-dandruff actives probably did most of the work.
Can zinc PCA be combined with other actives?
Yes. It is usually paired with niacinamide or salicylic acid. Watch for chelating agents in the formula, which can bind zinc.
07References
- Armanious YM, Neaz OS, Abdelghany AH, et al. Efficacy and tolerability of a multi-targeted anti-acne regimen incorporating salicylic acid, prebiotics, and zinc PCA: a 30-day clinical trial. J Cosmet Dermatol. 2026;25(7):e71034. Link
- Ge L, Liu Z, Xu S, et al. A cohort clinical study on the efficacy of topical salicylic acid/piroctone olamine dandruff pre-gel and cleanser in improving symptoms of moderate to severe seborrheic dermatitis of the scalp. J Cosmet Dermatol. 2025;24(1):e16742. Link
- Patel MN, Patel NK, Merja AM, Patnaik S. Clinical evaluation of the efficacy, safety, and in-use tolerability of a Diacnemide-containing acne kit (facial serum and cleanser) regimen for the synergistic management of facial acne in adults. Cureus. 2024;16(9):e69968. Link
- Zou P, Du Y, Yang C, Cao Y. Trace element zinc and skin disorders. Front Med. 2023;9:1093868. Link
- Andrade JP, Wagemaker TAL, Mercurio DG, Maia Campos PMBG. Benefits of a dermocosmetic formulation with vitamins B3 and a B6 derivative combined with zinc-PCA for mild inflammatory acne and acne-prone skin. Biomed Biopharm Res. 2018;15(2):214–223. Link
- Brandt S. The clinical effects of zinc as a topical or oral agent on the clinical response and pathophysiologic mechanisms of acne: a systematic review of the literature. J Drugs Dermatol. 2013;12(5):542–545. Link
Used in: Acne & oil control
Update log
- Evidence reviewed and page published by CSL scientists
This page summarises published research for brands and formulators. It is general information, not medical advice, and results in studies depend on the full formula tested.
