Have been prescribed celexa & cymbalta, (duloxetine) but neither instructs morning or night. does it matter when i take them- what about 1 morning & 1 night?

Not necessarily: A time that you have to take them. You could take either in the morning or the evening. Two things best determine when it may be best for you to take these medications 1)how and when can you best make sure you consistently take the medication 2) is either medication activating(wakes you up) or sedating(makes you sleep). It sometimes take a bit of time to best figure out what works best for you.

Yes can matter: Our bodies have circadian rhythms that can effect how we respond to diet and medications. You should consult the prescribing doctor for exact instructions on when to take the clexa and cymbalta (duloxetine). If they may work better by taking them in the morning or in the evening but it might require trial and error to figure out.

That's good thinking: both of those drugs can cause sleepiness or can be activating, all that depends on the dose, the other medications you take, and your individual response to medication. Trying on one day and another the next in the morning would help you figure out how each affects you. When starting new drugs I prefer to try only one for a bit, then add the other. IfU have a rxn U need 2know which drug caused it.