Hydroquinone

INCI: Hydroquinone
Also known as: HQ, 1,4-Dihydroxybenzene
BrighteningbrighteningsyntheticStrong evidenceNot for pregnancyPrescription only
85
Skinlumis Rating
Comedogenic
0/5
Irritancy
3/5
Best applied
PM
Effective range
2%–4% (Rx)
How It Works

The gold-standard pharmacologic depigmenting agent. Highly effective for melasma; long-term use risks ochronosis if uncontrolled.

Inhibits tyrosinase and damages melanosomes selectively in melanocytes, reducing melanin production.

pH Range
5.0–6.0
Benefits
  • Strongest depigmenting agent
  • Effective for melasma
  • Used in Kligman triple combination
Proven For

What the evidence supports.

MelasmaPIHSun spots
Best For
  • All skin types
Avoid If
  • Pregnant
  • Breastfeeding
  • Long-term use without breaks
Layering Order
4/10

Mid-routine serum or treatment step.

Max Safe Concentration
4% Rx

Concentration range in well-formulated products: 2%–4% (Rx)

Seasonal Use

Best autumn/winter cycles; off for summer with strict SPF.

For Estheticians & Professionals

Cycle 12 weeks on / 12 weeks off to prevent ochronosis. Mandatory SPF.

Prescription Only

Hydroquinone is a regulated medication. Use only under the guidance of a licensed physician or dermatologist. The information here is educational, Skinlumis does not dispense prescriptions or provide medical advice.

Clinical Evidence

The research behind Hydroquinone.

3 peer-reviewed studies

Every claim on this page traces to published research. Findings below are drawn from randomized trials and systematic reviews, each links to the study on PubMed.

Randomized Controlled Trial
Vitamin C showed comparable efficacy to hydroquinone for melasma treatment.
Espinal-Perez LE, Moncada B, Castanedo-Cazares JP
International Journal of Dermatology, 2004
View Study →
Randomized Controlled Trial
Niacinamide inhibits melanosome transfer to keratinocytes, reducing hyperpigmentation by up to 35%.
Hakozaki T, Minwalla L, Zhuang J et al.
British Journal of Dermatology, 2002
View Study →
Randomized Controlled Trial
Azelaic acid comparable to hydroquinone for hyperpigmentation with superior safety across all Fitzpatrick types.
Balina LM, Graupe K
International Journal of Dermatology, 1991
View Study →
Pairs Well With
TretinoinTopical corticosteroid (in Kligman)
Conflicts With
Benzoyl Peroxide (causes staining)
Your Skin Compatibility

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The science behind Hydroquinone

3 studies from the Intelligence Vault that discuss Hydroquinone.

Browse the Vault →