Monobenzone Clinical Study & Medical Information

Vitiligo is among one of the most common dermatological disorders, affecting up to two percent of the population worldwide. A chronic and usually progressive disorder, vitiligo presents discretely before 20 years of age, although first presentation in later life may also occur.

Clinically, it appears as one or more well-circumscribed, hypopigmented, white macules or patches. This is due to the acquired autoimmune destruction of melanocytes, most often in areas of greater pigmentation, such as the face and dorsum of the hands where they are most exposed to UV radiation.

Apart from the cosmetic appearance, it is usually asymptomatic, although there is a greater tendency for sunburns and pruritis. The undesirable aesthetic properties of vitiligo, especially facial, may result in significant negative psychosocial effects, notably a rate of depression twice that of the general population.

In some cultures, the depigmentation of vitiligo is thought to result from sexually transmitted infections or leprosy, and can have a damaging effect on educational, social, and employment opportunities. Studies have shown that vitiligo is associated with a greater burden of disease to patients, especially those in populations with dark skin.

There is No Cure — But Two Main Approaches Exist

Current treatment for vitiligo attempts to either increase (repigmentation) or decrease (depigmentation) pigmentation in order to achieve cosmetically pleasing results and increase the patient's self-esteem.

Repigmentation Treatments

Repigmentation tends to require a prolonged treatment course and yield minimal positive results. Strong topical steroids are generally the first line of treatment, with only a 50–75% repigmentation rate. Tacrolimus (an immunosuppressive) and calcipotriene (a vitamin D analogue) are alternative topical repigmenting agents.

When such treatment fails, psoralen plus ultraviolet A radiation (PUVA) and narrow-band ultraviolet B radiation (NB-UVB) are effective alternatives. However, PUVA can be carcinogenic and NB-UVB has low efficacy; both require prolonged treatments.

Depigmentation — When Monobenzone is Indicated

Due to the difficulties with repigmentation, it is often easier to achieve depigmentation, especially when vitiligo affects more than 50 percent of the body. It is, however, a more aggressive approach and its use is considered on an individual basis because of the irreversible changes and increased sensitivity to sunburn.

Monobenzone (MBEH) is usually the treatment of choice for depigmentation therapy in severe cases of vitiligo, used in concentrations of 20 to 40 percent to achieve the desired permanent depigmentation.

Patient Background

A 37-year-old African man with advanced vitiligo on the face, neck, trunk, and upper and lower extremities was referred for dermatological treatment for cosmetic reasons. The onset of the vitiligo began at least 20 years prior to consultation. Previously, the patient attempted repigmentation through various treatment modalities unsuccessfully — including NB-UVB and several months of tacrolimus ointment 0.1% twice daily without any sign of improvement.

Treatment Protocol

After initial observation and a failed trial of Pathak's formula (4% hydroquinone with 0.1% tretinoin), a compounded formulation of 20% monobenzone cream was applied to pigmented areas of the face and neck once daily. The patient was instructed to wear sunblock while outdoors. Some slight skin irritation occurred, managed with hydrocortisone butyrate 0.1% cream.

Treatment was then intensified to twice daily for three and a half months, after which depigmentation was extremely satisfactory, matching the bleached areas of vitiligo.

Treatment Timeline

Outcome & Conclusions

The quick and effective results achieved with MBEH, following the ineffective 10-week trial of Pathak's formula, demonstrates the drug's effectiveness. Control three years later confirms a sustained and permanent depigmentation as well as a very satisfied patient.

This case highlights the importance of timely aggressive treatment of vitiligo and its effect on the patient's quality of life. Physicians should not shy away from prescribing the more potent treatments, due to the significant negative psychosocial impact vitiligo can have.