We report 2 women with PD who developed hair loss while being treated with the dopamine agonists Mirapex and Requip. The hair loss reversed partially after the drugs were discontinued. Both women were postmenopausal and had no history of hair loss or other dermatologic disorders. Reversible hair loss has been described in patients treated with Parlodel, Permax, or Sinemet, but not in association with other dopamine drugs.
This report adds to the scant literature describing reversible, alopecia caused by dopamine drugs. Both our patients developed hair loss while being treated with Mirapex. However, while in the first case the hair loss reversed after Mirapex was substituted with Requip, in the second patient the hair loss continued and worsened after the change to Requip and only the complete discontinuation of the dopamine agonists and initiation of Sinemet led to the cessation of hair loss.
Thus, although the use of Mirapex was associated with hair loss in both patients, the effect of Requip on hair loss or growth is less clear. Further, both patients were concomitantly treated with amantadine, and it is possible that hail loss developed as a consequence of the interaction between amantadine and the dopamine agonists.
The only previous reports of hair loss associated with the use of dopamine agonists have included patients treated with Parlodel and Permax. An additional report described hair loss caused by Sinemet. As in our cases, the hair loss associated with Parlodel treatment started after a period of weeks or months after the introduction of therapy and ceased with the discontinuation of the drug. It is also of note that both our patients are women and that the Parlodel -induced hair loss was described only in women. Hair loss was described in a patient taking Permax; however, the sex and age of the patient were unspecified.
The mechanism for dopamine induced hair loss is unclear. Dopamine receptors are present in the hair follicle, where they appear to regulate melanin production but have no known role in regulating hair growth. Although rare, hair loss may be a side effect in women treated with dopamine agonists that can be at least partially reversed after the discontinuation of the drugs.
