Take a different approach and evaluate what his last meal of the day includes. Is it something that would keep him awake, such as a dessert with high sugar content? Is there anything else he eats that's a stimulant?
Have you tried giving him turkey in the evening; it naturally contains L-tryptophan, which can contribute to sleepiness. (Remember those times after a Thanksgiving dinner when the older folks fell asleep and took naps?) It can be bought at a drug store or in the vitamin section of supermarkets.
It might or might not stop the talking at night, but if it induces sleep w/o meds, it's certainly worth a try. (I always fall asleep more quickly when I have turkey in an evening meal.) You don't have to cook a big turkey weekly though! You can create meals with turkey ingredients.
Let the doctor know that the medication that was prescribed is not working as it should. Often medication is a try and see if this works as it should. In most cases all goes well but in some getting the correct medication and or the correct dose can be a challenge. If possible try keeping him as busy as possible during the day. Physical activity is important. Avoiding napping so that he will sleep better at night. Lighter evening meal Stick to a routine. Same time up in the morning and same time to bed at night.
With dementia patients there will be behaviors that will come and go. As soon as one goes away a different one will take its place. No one can tell you how, when or what. The best solution is to provide a distraction. Have you tried a music radio or television for him to listen to or watch at night? Read the warning below about using drugs.
That's the result of trying to convert your home into a dementia unit. Your husband belongs in a memory care unit or nursing home. Using psychotropic medicines is complicated. There are many unwanted side effects, among them the worsening of the dementia and some others more serious.
Definitely talk to his doctor about either upping the dosage or changing his nighttime medication(s) like BarbBrooklyn said below, but also until then, is it possible for you to sleep in a separate bedroom with your door closed(or his)so you can't hear him? You can always put an inexpensive security camera or baby monitor in his room, so you can keep an eye on him if needed. You're going to need your sleep in order to continue on this journey with your husband, so I hope you get things figured out soon.
Have you tried giving him turkey in the evening; it naturally contains L-tryptophan, which can contribute to sleepiness. (Remember those times after a Thanksgiving dinner when the older folks fell asleep and took naps?) It can be bought at a drug store or in the vitamin section of supermarkets.
It might or might not stop the talking at night, but if it induces sleep w/o meds, it's certainly worth a try. (I always fall asleep more quickly when I have turkey in an evening meal.) You don't have to cook a big turkey weekly though! You can create meals with turkey ingredients.
https://www.hopkinsallchildrens.org/Patients-Families/Health-Library/HealthDocNew/Does-Eating-Turkey-Make-Me-Sleepy
This article helps explain the reaction of turkey on sleepiness.
Often medication is a try and see if this works as it should. In most cases all goes well but in some getting the correct medication and or the correct dose can be a challenge.
If possible try keeping him as busy as possible during the day. Physical activity is important.
Avoiding napping so that he will sleep better at night.
Lighter evening meal
Stick to a routine. Same time up in the morning and same time to bed at night.
You're going to need your sleep in order to continue on this journey with your husband, so I hope you get things figured out soon.