Topical agents such as hydroquinone and azelaic acid play a central role in the management of melasma by reducing hyperpigmentation through inhibition of melanogenesis. Hydroquinone is considered a first-line topical treatment due to its potent ability to inhibit tyrosinase, an enzyme critical for melanin production, thereby lightening hyperpigmented patches characteristic of melasma NICE NG198. Azelaic acid also inhibits tyrosinase but has additional anti-inflammatory properties, making it a useful alternative or adjunct, especially in patients who may not tolerate hydroquinone well or have contraindications NICE NG198.
Both agents have demonstrated efficacy in improving melasma, with systematic reviews and meta-analyses indicating that azelaic acid can be as effective as hydroquinone, with a potentially better safety profile and fewer adverse effects such as irritation or ochronosis Albzea et al. 2023. The choice between them may depend on patient-specific factors including skin sensitivity, risk of side effects, and treatment duration.
In clinical practice, these topical agents are often used in combination with other modalities such as sun protection and sometimes other topical or procedural treatments to optimize outcomes NICE NG198.
Key References
- NG198 - Acne vulgaris: management
- (Pérez-Bernal et al., 2000): Management of facial hyperpigmentation.
- (Sofen et al., 2016): Melasma and Post Inflammatory Hyperpigmentation: Management Update and Expert Opinion.
- (Albzea et al., 2023): Azelaic Acid Versus Hydroquinone for Managing Patients With Melasma: Systematic Review and Meta-Analysis of Randomized Controlled Trials.