Yes, opiates do, for a good deal of people, lessen anxiousness, nervousness, and tension to a considerable degree. Opiates have an effect on the perception of pain, itself, and in this sense I am speaking of pain so as to include any distress, physical or psychological. They don't tend to disinhibit one's demeanor like most sedative-hypnotics, but rather work by generating numbness and dulling the feelings of negativity within distress. I have found that, for me, opiates are better anxiolytics than any sedative-hypnotics, such as a benzodiazepine, barbiturate, or other GABAergic drug. Now, the consequences of using opiates for anxiety relief can vary, and for many be enormously negative, for opiates are insidiously addictive agents. I love them, but do beware. Also, it is probably ill-advised to discontinue your usual regimen of anti-anxiety drug(s), on account of withdrawal symptoms.