Hi SP Tan,
You are suffering from Post-Inflammatory Hyperpigmentation.
For fast results, I highly recommend a combination of the following (the non-cream methods are more costly) :
- De-pigmenting creams like Hydroquinone / Arbutin. Daily application twice a day is recommended.
- Q-switched ND:Yag laser in PTP laser toning mode or Chemical Peels. Highly recommended to do it every 2-3 weeks for the laser and 4-6 weeks for the chemical peel.
You have to balance the cost of treatment vs your urgency to remove the patch. With a good de-pigmenting cream, you can lighten or remove the pigments in 6-9 months time anyway and that’s way more cost-effective.