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Hi, could you tell me where you found that please? Thanks Maryse > Psychiatric Adverse Effects > > Estimates of the prevalence of dementia in Parkinson's disease vary > widely, but is most commonly placed in the 15%-20% range. The prevalence > of dementia in Parkinson's disease is key in assessing potential > psychiatric effects of levodopa. > > Levodopa's most common psychiatric adverse effects can take a variety of > forms, including confusion, agitation, visual hallucinations, paranoia, > psychosis, and hypersexuality. The emergence of these adverse effects > can compromise drug therapy, since a levodopa dose reduction may be > necessary.3,6 > > Nocturnal Phenomena > > Psychiatric effects induced by levodopa will sometimes present initially > as nocturnal phenomena, such as vivid dreams, nightmares, disturbed > sleep patterns, and visual hallucinations. > > Improvement can occasionally be achieved by reducing or stopping the > last evening dose or giving the last dose earlier in the evening.1,8 > Levodopa-induced psychiatric effects are believed to be progressive.3 As > a result, experts differ as to whether visual hallucinations that are > not accompanied by distress require a prompt decrease in the levodopa > dosage. Frequently, a compromise must be reached between some > hallucinations and suboptimal control of symptoms. > > Psychotic Symptoms > > Pharmacodynamic changes from age-related changes in the brain-such as > reduced cerebral blood flow, increased permeability of the blood-brain > barrier, and increased conduction time-may be responsible for greater > sensitivity to centrally-acting drugs.8 As a result, elderly patients > are more vulnerable to psychosis. The emergence of psychotic symptoms > requires a review of all potentially causative medications. The > medications with the greatest potential for inducing psychosis but > lesser effects on parkinsonian symptoms should be discontinued first. > For example, anticholinergic agents should be discontinued first, > followed by selegiline, amantadine, and, finally, dopamine agonists. > > If a patient is not receiving any of these medications or if withdrawal > of these agents is not effective, then a reduction in the levodopa > dosage should be considered.6 Use of neuroleptic agents must be > considered if the levodopa dosage reduction results in intolerable > parkinsonian symptoms (Table 3). Certain neuroleptic agents, such as > haloperidol and chlorpromazine, are contraindicated because they block > both limbic and striatal dopamine receptors and aggravate parkinsonian > symptoms. Less potent neuroleptic agents, including thioridazine11 or > molindone,12 may be considered for use, but their effectiveness is > limited. ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn