This study aims to investigate the safety of serum product containing low dose of alpha hydroxy acid (AHA) i.e. 1% Glycolic acid and Lactic acid and Polyglutamate acid derivatives (PGA) for post-inflammatory hyperpigmentation skin in Malaysia. The study duration is 8 weeks and the skin assessment will be carried out at baseline, week 4 and week 8.The main questions this study aims to answer are:

1. To investigate the safety of serum containing low concentration AHA (1% Glycolic acid and Lactic acid) and PGA for post-inflammatory hyperpigmentation skin among Malaysian.
2. To assess the patient satisfaction after using serum containing low concentration AHA (1% Glycolic acid and Lactic acid) and PGA among Malaysian.

Inclusion Criteria:

• Malaysian from 18 to 40 years old.
• Participants with post-inflammatory hyperpigmentation (PIH).

Exclusion Criteria:

• Participant with known systemic or skin disease and any underlying medical illness
• Pregnant, breastfeeding women or planned pregnancy during the study period.
• Had reported history of dermatologic conditions (i.e. Atopic dermatitis, psoriasis) or known allergies to any ingredients that may be found in the product.
• Had any cosmetic procedures such as Botox, laser and light treatment, facial surgery, chemical peel and any procedures that may improve skin texture 1 month before the study.
• Had history of taking isotretinoin for the past 6 or 12 month and AHA (alpha hydroxyl acids) containing products or any other products for treating hyperpigmentation skin or melasma 1 month prior to study.