Chemical Leukoderma Associated with Methylphenidate Transdermal System: Data From the US Food and Drug Administration Adverse Event Reporting System

OBJECTIVE

To identify and characterize cases of chemical leukoderma, an underrecognized adverse event, associated with the methylphenidate transdermal system (MTS) reported to the US Food and Drug Administration Adverse Event Reporting System (FAERS).

STUDY DESIGN

We searched the Food and Drug Administration Adverse Event Reporting System for reports of chemical leukoderma associated with MTS, received by the Food and Drug Administration from April 6, 2006 to December 23, 2014.

RESULTS

We identified 51 cases of chemical leukoderma reported with the use of MTS. The median age was 11 years; 43 cases reported leukoderma at or near the application site only, and 7 reported leukoderma at other parts of the body in addition to the application site; 1 case did not provide enough information to confirm the affected site. The time to onset ranged from 2 months to 4 years after the initiation of MTS. MTS was discontinued in 31 cases. Thirteen patients were prescribed treatment for repigmentation. Three cases reported continued spread of leukoderma after MTS was discontinued. Nineteen cases were diagnosed as vitiligo, including 5 cases reporting histologic features consistent with vitiligo. Leukoderma was persistent in all cases. The median follow-up interval after the discontinuation of MTS in 23 cases was 14 months.

CONCLUSIONS

As outlined in recent changes to the prescribing information for MTS, health care professionals need to be aware of the potential risk of chemical leukoderma caused by MTS, especially given that chemical leukoderma is often misdiagnosed as idiopathic vitiligo. MTS should be discontinued at the earliest sign of pigment loss and other treatment options considered.

Hand dermatitis: uncommon presentations

Hand dermatitis is a common diagnosis seen in dermatologic and general practice. It can present with typical morphology, but uncommon manifestations are possible. This review reports on common and uncommon presentations of irritant and allergic hand dermatitis focusing on uncommon localizations, time course, and morphology such as follicular, pustular, bullous, ulcerous, exudative erythema multiforme-like, purpuric, lichenoid, pigmented, and depigmented skin lesions. Clinical diagnosis can be challenging. Even histopathology is not always very helpful. Thorough evaluation of the patient's history and investigation of clinical morphology are the cornerstones of diagnosis.