It's chlordiazepoxide, a benzodiazepine. In fact the first benzo ever synthesised in the 1950's. It is used as a short term treatment of anxiety and also for acute alcohol withdrawals.
Mixing CNS depressants always has it's risks, however they will be a great combination. If you are both benzo and opiate naive then I would recommend going slowly and treading carefully here.
I figured it sedated but wasn't completely sure, but completely agree in that case both cns depressants, so take it slow and work your way up if you have to.
Combining benzos and opiates can be very dangerous, but I do believe it can be done responsibly. I don't know what your benzo and opiate tolerances are like though, so I can't give you an idea of what I'd recommend.