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Resume: on estime les cas de demence associes a la MP a 15-20% des MP. Elle peut etre importante dans l'assessement des effets psychiatriques de la Ldopa. Les effets psychiatriques de la ldopa les plus courants sont multiples: confusion, hallucinations visuelles, paanoia,psychoses, hypersexualite. Ces symptomes peuvent pousser a une baisse des doses de traitement ce qui peut amener a une baisse des capacites physiques. Les phenomenes nocturnes peuvent etre les prcurseurs: cauchemars, reves 'realistes', sommeil perturbe, hallucinations visuelles.. Le fait de reduire ou supprimer ou avancer les doses prises avant le sommeil peuvent ame;liorer ces problemes. A cause de phenomenes du au vieillissement, des phenomenes psychotiques peuvent survenir. De nouveau, ils peuvent etre combattus par une baisse de la posologie, arret des anticholenergiques, selegiline, amantadine, puis les agonistes. Si le patient prend aucun de ces medicaments, il faut penser a diminuer la ldopa. Des neuroleptiques peuvent s'ajouter pour ne pas devoir trop diminuer la ldopa. Certains neuroleptiques comme l'halperidol et la chlorpromazine sont contrindiques car ils aggravent les symptomes MP. Des neuroleptiques moins puissants comme la thiordazine ou le molindone peuvent etre utilises avec une moindre efficacite: > 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. > > --- > Outgoing mail is certified Virus Free. > Checked by AVG anti-virus system (http://www.grisoft.com). > Version: 6.0.408 / Virus Database: 230 - Release Date: 10/24/2002 > > ---------------------------------------------------------------------- > 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