Some further info on Lewy Body dementia and the drug issue, from UCSF (my boldface):
"ndividuals diagnosed with Lewy body dementias often have adverse reactions including confusion when taking medications that affect the brain, such as anti-anxiety drugs (examples: Valium®, Ativan®), anticholinergic drugs (examples: Benadryl®, Detrol®), and antiparkinson’s drugs (examples: Sinemet®, Mirapex®). To avoid adverse reactions to medications, physicians should carefully monitor medications, introduce medications one at a time and prescribe minimal doses when possible.
An extensive neurological and neuropsychological evaluation is essential for Lewy body dementia diagnosis. Structural brain imaging (e.g., MRI or CT) and laboratory tests are used to rule out other diagnoses. Lewy body dementias can be difficult to diagnose because they can resemble and overlap with other causes of dementia like Alzheimer’s disease, other parkinsonian syndromes (examples: progressive supranuclear palsy, multiple system atrophy, corticobasal syndrome), and vascular dementia. As in many neurodegenerative diseases, a definitive diagnosis in only available after an autopsy. However, clinical diagnosis by experienced providers can be quite accurate and reliable.
Onset of the disorder usually occurs in older adults, and disease risk increases with age. There is substantial variability in the course of the illness. In general, symptoms progress over several years as cognitive decline becomes more prominent and psychiatric symptoms emerge or worsen. The progression of symptoms represents increasing pathology in the brain including more widespread Lewy bodies, loss of neurotransmitters (examples: dopamine and acetylcholine) and nerve cell death.
Management and treatment of Lewy body dementias
Lewy body dementia patients are often frail, and their symptoms can worsen quickly when faced with infection, medication reactions or changes in the environment; these risks should be closely monitored.
Nonpharmacologic interventions, including physical, occupational and speech therapy, community resources and assistance with home care should always be considered. The motor symptoms of Lewy body dementias are generally treated with dopaminergic therapies. These medications are usually helpful in decreasing the severity of motor symptoms. However, it is advisable for these medications to be initially prescribed at a low dosage and gradually titrated upwards as necessary given the possibility of potential side effects such as worsening confusion and hallucinations. Cognitive symptoms of Lewy body dementias are often treated with cholinesterase inhibitors (e.g., Rivastigmine®, Aricept®). These medications can improve the attention deficits, cognitive fluctuations, neuropsychiatric symptoms (e.g., hallucinations, apathy, anxiety), and sleep disturbances by boosting acetylcholine in the brain, a neurotransmitter that is severely reduced by these diseases. Memantine has also been tried for treatment of cognitive impairment in Lewy body dementias. In general, the results have suggested that this drug is well-tolerated but not reliably effective. Depression is very common in Lewy body dementias and can be treated with antidepressant medications.
For psychotic symptoms (e.g., hallucinations or delusions) that are troublesome to the patient and/or family and that are non-responsive to psychosocial interventions (e.g., making changes in the patient’s environment) or cholinesterase inhibitor treatment, atypical second generation antipsychotic medications such as risperidone (Risperdol®) and quetiapine (Seroquel®) can be tried but must be used cautiously due to the risk of motor and cognitive side effects. Older, first generation antipsychotic drugs such as haloperidol (Haldol®) or chlorpromazine (Thorazine®) should be avoided because they can cause extreme adverse reactions in many Lewy body dementia patients. A patient treated with these drugs could become catatonic, lose cognitive function and/or develop more muscle rigidity.
The symptomatic treatments available and described above do not slow down the disease course. The current search for disease-modifying drugs is focused primarily on preventing the misfolding and buildup of alpha-synuclein pathology in the brain."
There is actually some exciting news due out soon re progress in understanding Dementia with Lewy Bodies - I'll post it here soon.