**3.1 Monobenzyl ether of hydroquinone (MBEH)**

MBEH (monobenzone, p-benzyloxy-phenol) is the most common topical depigmenting agent used mainly because it is the only product approved by the United States Food and Drug Administration (USFDA) for depigmentation in vitiligo, if the affected body surface area is more than 50% [1]. It is a hydroquinone (HQ ) derivative and was first introduced in 1930s. MBEH is the first-line agent for depigmentation therapy in vitiligo patients.
