Sleep can be a particular problem in people with LBD.
The Society Factsheet advises as follows
"Sleep disturbance
Steps can be taken to help a person with DLB have more restful nights. Increasing physical exercise, having a regular bedtime and getting-up time, and reducing daytime napping can all help. It can also help to avoid alcohol, caffeine and nicotine close to bedtime, and to keep the bedroom quiet and at a comfortable temperature.
Practical steps can be taken to make the area around the bed safe – remove sharp objects and put a mattress alongside the bed in case the person falls or jumps out.
Carers should also talk to the GP about sleep problems. Drugs such as clonazepam or melatonin can be effective treatments."
The GP would be my first port of call. I hope that's of some help.