Dark spots , whether caused by acne , scars or another skin concern, are not only annoying, but also hard to get rid of. Fortunately, a lesser-known ingredient called tranexamic acid, known for brightening skin and fading dark spots and melasma (a type of pigmentation), may come in handy. Tranexamic acid is available to take orally via a prescription or as a topical in over-the-counter serums. Experts I spoke to say the oral version is much more potent, but also comes with more side effects.