Quote:
Originally Posted by boann
However, there has been an incessant contrasting of dopamine agonists with levodopa in this context -- where levodopa is always presented as not causing these problems - even when, as is almost always the case, the person who has experienced ICDs is taking levodopa in addition to a dopamine agonist -- levodopa is always exonerated.
Forgive me if I've gone overboard, but here are probably far too many examples of what I'm talking about:
Pathological gambling caused by drugs used to treat Parkinson’s disease
Dodd, et al, Archives of Neurology 2005
Quotes from paper:
“None developed new gambling or an increase in gambling while receiving levodopa monotherapy”
“Although levodopa therapy might have been a contributory factor [because everyone who gambled was taking it in addition to the dopamine agonist], none developed these problems when receiving levodopa monotherapy, and 3 patients had not been treated with levodopa. The relationship of pathological gambling to dopamine agonist therapy in these cases is striking”
“This article, as well as others from this systematic review, revealed that all patients [who gambled] were taking a dopamine agonist [and levodopa, but the authors leave that out of this sentence] but none were receiving levodopa monotherapy.””
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I am quoting Boann and starting a new thread on levodopa vs. agonists and
their role in obssessive-compulsive disorder or the newly named, dopa agonist blamed, ICD. Well, there is so much interesting stuff flying back and forth, I think it is getting lost in the original thread.
I think you ask the key question early on...
Why is levodopa always exonerated? It can't just be author bias; there are far too many studies isolating agonists so there must be a rigorous statistical measure being used (we can only hope).
I became curious as to how agonists fared in other treatments. It's used as a monotherapy in treating RLS and in 2007, The Mayo Clinic was the first to report correlation between compulsive behaviors and agonist treatment of RLS.
The newest study I could find further isolates:
Among the study patients with PD, new-onset compulsive gambling or hypersexuality was documented in 7 (18.4%) of 38 patients taking therapeutic doses of dopamine agonists but was not found among untreated patients, those taking subtherapeutic agonist doses, or those taking carbidopa/levodopa alone. Behaviors abated with discontinuation of agonist therapy or dose reduction.
from "Frequency of New-Onset Pathologic Compulsive Gambling or Hypersexuality After Drug Treatment of Idiopathic Parkinson Disease"
J. Michael Bostwick, MD, Kathleen A. Hecksel, MD, et al.
MayoClinic Proceedings. April 2009.
I think the clincher is that stopping or reducing the agonist ended the behavior. I do wonder if the compulsive behavior problems are more prevalent in males (anecdotally, I hear more horror stories from them, but more men than women have PD) and what ages are prevalent when looking at many different studies? In the end, I think this goes along with the fact that some of us are more prone to addictive behaviors to begin with...drug addiction also center on dopamine transmission. If you think of how agonists work vs. straight levodopa, I'm not surprised that given the right environment an agonist can do more harm than good.
Laura