Has he had a sleep study done to rule out sleep apnea? He could try Trazodone, which is commonly prescribed for insomnia as one side effect is sleepiness. He could also try a low dose of melatonin. I take 2.5mg melatonin 15 minutes before bed along with 50-75mg trazodone. I also take a sleep gummy with 10mg CBN and 5mg THC (Minny Grown brand called Highbernate). Take with a light snack (I eat yogurt) as it helps both the Trazodone and CBN last longer in your system. Another drug prescribed for sleep is Mirtazapine, about 7.5 mg. It has a longer half-life than Trazodone so might make the sleepiness last into the next day.

@joyceinil I have found Sleep8 from NiHealth works well for me it is all natural and I did not wake up in the morning with the typical hangover that I get when I take over-the-counter or prescription sleep medication. My doctor recommended trying it because I didn’t do well with the prescription he recommended. I will say it took about three days of taking it consistently before I began to sleep through the night. Sleep8 worked for me. Hope this helps.