Dropped head syndrome with necrotizing myopathy: A drug class effect confirmed by 3 repeated exposures to non ergolinic dopamine agonists, due to L-Dopa phobia

Background: Dropped head syndrome (DHS) or antecollis is a common complication in multiple system atrophy and a rare complication in L-Dopa responsive Parkinson's disease (PD). Few reports described DHS as a side effect of dopamine agonists (DAs) treatment in PD, mostly in Asian patients. Case report: We report a single case of DHS in a 56 year-old Caucasian male patient affected by PD. Insistent and repeated DA treatment with pramipexole, ropinirole and rotigotine was due to L-Dopa phobia and DA withdrawal syndrome. Each DA treatment was accompanied by DHS recurrence with muscle enzyme increment. Results: The cause of DHS was identified by muscle biopsy as a necrotizing myopathy. Repeated administration of different DAs, inducing recurrence of DHS shows that DHS was due to a drug class effect of non ergolinic dopamine agonists. Conclusion: The exposure to three different non ergolinic DA induced DHS in this patients, suggesting a role of DA receptor sensitivity in the pathogenesis of DHS. Our case report also calls attention to a possible rare side effect of non ergolinic dopamine agonists go along with two other complications of PD treatments, L-Dopa phobia and dopamine agonist withdrawal syndrome, which prompted the repeated exposures. © 2015 Elsevier GmbH.