Standard doses of each should be fine unless you have a known liver issue, or have decided to drink a litre of grapefruit juice today.
The concern is normally due to enzyme inhibition increasing concentrations of either, but in a healthy person the chances of an interaction are minimal.
As a seperate point benadryl is not the healthiest thing to help you sleep, personally I’m a fan of magnesium glycinate 300mg and L-Tryptophan 600mg; clean sleep that still works just as well after taking it for 6 years as it did the first month.
Benedryl as an occasional sleep aid isn’t great, but regular use is correlated with an increased risk of dementia.
Take a half dose of each if you’re still concerned.
Devil’s lettuce, Mary Jane and “marahuana” (in the Hank Hill voice) are probably my favorites that immediately come to mind