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Another reason to avoid them as long as possible... Nic 57/16 2010/1/12 mschild <[log in to unmask]> > Reducing Dosage of Parkinson's Drugs Can Cause Symptoms Similar to Those of > Cocaine Withdrawal > ScienceDaily (Jan. 11, 2010) — New research has shown that reducing the > dosage > of dopamine agonist (DA) drugs, a mainstay treatment for Parkinson's > disease > (PD), sometimes causes acute withdrawal symptoms similar to those reported > by > cocaine addicts -- including anxiety, panic attacks, depression, sweating, > nausea, generalized pain, fatigue, dizziness and drug cravings. These > symptoms > can be severe, and are not alleviated by other PD medications. > For the first time, researchers have defined this phenomenon, which they > call > dopamine agonist withdrawal syndrome, or DAWS. Led by a physician-scientist > at > NewYork-Presbyterian Hospital/Weill Cornell Medical Center, the study is > reported in the Jan. 11 Archives of Neurology. > "Like cocaine and methamphetamines, dopamine agonists work by stimulating > the > reward pathways in the brain. For this reason, it makes sense that they > would > engender similar withdrawal symptoms, particularly in those with high > cumulative drug exposure," says senior author Dr. Melissa J. Nirenberg, > associate director of the Parkinson's Disease and Movement Disorders > Institute > at NewYork-Presbyterian Hospital/Weill Cornell Medical Center and assistant > professor of neurology and neuroscience at Weill Cornell Medical College. > Dopamine agonists are highly effective drugs that are prescribed to many > Parkinson's patients to avoid side effects of the "gold standard" drug > L-DOPA, > particularly abnormal involuntary movements referred to as dyskinesias. (L- > DOPA was perfected by Dr. George C. Cotzias of Cornell University Medical > College in the late 1960s; dopamine agonists have been available since the > 1990s.) DAs are also FDA-approved for treatment of restless legs syndrome, > and > used off-label for other conditions such as depression and fibromyalgia. In > the > United States, there are currently two DAs on the market -- pramipexole > (Mirapex®) and ropinirole (Requip®, Requip XL®). > In recent years, there have been increasing concerns about DA side effects, > and > particularly the fact that they can cause uncontrolled, compulsive > behaviors > known as impulse control disorders (ICDs). ICDs are reported to occur in > about > 14 percent to 17 percent of PD patients who use these drugs, and also occur > in > people who use DAs to treat other medical conditions. In 2006, Dr. > Nirenberg > published research linking the use of DAs to compulsive eating; others have > linked the drugs to behaviors such as compulsive gambling, buying, > hypersexuality and Internet addiction. Patients are often unaware of these > addictive behaviors, or may not discuss them with physicians because they > are > in denial, embarrassed by their symptoms, or unaware that they are a > medication side effect. > "Impulse control disorders stemming from use of dopamine agonists can be > detrimental to a patient's financial, social and physical well-being. Our > research identifies another concern -- namely that some patients experience > severe, even intolerable, withdrawal syndromes when their dosage is > reduced. > In this context, it's very important that physicians and their patients use > DAs judiciously, and exercise caution when they are tapered," says Dr. > Nirenberg. > Study Design and Findings > In the current study, Dr. Nirenberg and first author Christina A. Rabinak, > a > third-year medical student at Weill Cornell Medical College, performed a > retrospective analysis of a cohort of 93 people with Parkinson's disease, > of > whom 40 received DAs, and 26 tapered a DA for any of a variety of reasons > -- > most commonly because of ICDs. Among those who tapered a DA, five patients > (19 > percent) experienced DAWS. Two of the subjects with DAWS recovered fully, > but > three of the five were unable to successfully discontinue the drug because > of > severe withdrawal symptoms. These three study participants are currently > living with their ICDs. > The NewYork-Presbyterian/Weill Cornell researchers made several > observations > about DAWS: > DAWS only occurred in patients with ICDs, and not in those who tapered DAs > for > other reasons. However, only one-third of patients with ICDs experienced > DAWS. > Withdrawal symptoms were only alleviated by increasing the DA dosage. Other > treatments, including high doses of L-DOPA, antidepressants, tranquilizers > and > psychotherapy, were ineffective. > DAWS correlated with cumulative exposure to DAs, with the most severe > symptoms > occurring in patients with the greatest DA exposure. > Subjects with DAWS had milder physical disability than those without. > The Message for Patients & Physicians > "DAWS has been difficult to identify because its symptoms are 'invisible' > -- > mainly psychological in nature," says Dr. Nirenberg. In fact, both patients > and physicians have mistaken DAWS for a mental health condition such as > anxiety or depression. DAWS has also been misinterpreted as a manifestation > of > PD itself, or of wearing off between doses of medication -- something > disproven > by the fact that the symptoms are not alleviated by even very high doses of > L- > DOPA. > Dr. Nirenberg recommends that patients "educate themselves about DA side > effects, involve family members and friends in monitoring their behavior > for > possible ICDs, and promptly inform their physicians if they experience ICDs > or > DAWS." The authors also provide specific advice for clinicians who use DAs: > (1) > avoid prescribing high doses of DAs, (2) closely monitor DA-treated > patients > for signs of ICDs, (3) warn patients of the risks of DAWS, (4) taper DAs at > the first sign of ICDs, and (5) closely monitor patients when tapering DAs, > particularly those with ICDs. As for future directions, Dr. Nirenberg > stated > "the most important unanswered questions are how to reduce the risk of > DAWS, > and how to treat DAWS once it occurs." > The current study was supported by the Parkinson's Disease Foundation. > > ---------------------------------------------------------------------- > To sign-off Parkinsn send a message to: mailto: > [log in to unmask] > In the body of the message put: signoff parkinsn > ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn