Levodopa May Be Addictive
Popular Parkinson's Disease Treatment May Lead to Addiction
Nov. 24, 2003 -- People with Parkinson's disease may become
completely dependent upon a drug commonly used to help restore their muscle
function and retain their independence.
A new report suggests the popular Parkinson's disease drug
levodopa may be addictive, especially in people who use the drug and do not
actually have Parkinson's disease.
Although more research is needed on the possible addictive
properties of levodopa in people with Parkinson's, researchers say the findings
may help explain why people with Parkinson's disease frequently crave their
next dose of levodopa.
"Although the impatience, the emotional dependence, and the
craving to receive the next dose of levodopa might resemble addiction, this
behavior has been attributed to the urge to overcome the incapacitating motor
dysfunction," write researcher Israel Steiner, MD, of Hadassah University
Hospital in Jerusalem, Israel, and colleague.
Stopping Levodopa May Lead to Withdrawal
But in a report published in the Nov. 25 issue of the journal
Neurology, researchers describe five people who displayed signs of
addiction after being treated with levodopa for restless leg syndrome or an
incorrect diagnosis of Parkinson's disease.
According to the report, the patients suffered from
psychological and physiological symptoms of addiction and withdrawal from the
levodopa when they were weaned off the drug.
For example, one woman with restless leg syndrome who took
levodopa increased her dosage of the drug by seven times without consulting her
doctor and suffered from agitation, palpitations, diarrhea, and sweating when
doctors tried to replace levodopa with another drug.
Researchers say that because levodopa works on the same reward
center of the brain that has been associated with the addictive properties of
other drugs like cocaine, nicotine, and alcohol, it's plausible that addiction
to levodopa may develop.
They say their observation of the potential addictive
properties of levodopa should be examined in larger studies involving people
with and without Parkinson's disease.