Is Lithium-900, Temazepam-150, Duloxetine-60, Divalproex-500 And Clonazepam-1 The Right Dosage?

My nephew is taking 900 mg of lithium 1 at morning and 2 at night in addition to 150 mg of temazepam at bedtime. He sleeps most of the day. Doesn't this need to be lower? Also he takes duloxetine de caps 60 mg twice day, divalproex sod er 500 mg twice day, and clonazepam 1 mg twice a day. The man is 59 yrs old and is having trouble talking, walking most everything is just sleep.