You should definitely discuss this with a pharmacist or your doctor. Both these drugs have sedating effects. One website stated that 

"Antidepressants, antihistamines, and sedatives used for insomnia, other pain medications, muscle relaxants, anxiety medications, and even alcohol can cause a dangerous level of sedation or unconsciousness, and even prove fatal, when combined with Darvocet" 

These medications depress central nervous system activity. If you take too much of them at once they can put you into a sleep that you don't wake up from. This doesn't necessarily mean you can't take the two together but it does mean that you should speak with a qualified professional about what amounts are safe (if any) for you.