It is a rare side effect from the agonists. My previously thick hair fell out while I was taking Mirapex. No one believed me, my thyroid tests were normal. I stopped all drugs on Halloween, moved with difficulty and my hair eventually grew back but thinner (at least it doesn't fall out in clumps and is no longer "fairy or angel hair").

My dermatologist reported it as an "adverse effect" to the drug co. and fda, did research and published an article with photos of the top of my head, before and after. See Telogen effluvium associated with the dopamine agonist pramipexole in a 55-year-old woman with Parkinson's disease
Journal of the American Academy of Dermatology, Volume 55, Issue 5, Pages S103-S104
K. Katz, G. Cotsarelis, R. Gupta, J. Seykora

That was me, a few years ago.

Hate to mention the competition, but there's a long thread on "hair loss" on Patients Like Me.