Doxepin, a drug used to treat depression, may be the latest way to help people quit smoking, a new study suggests.

Smokers who took doxepin before and during abstinence showed less craving, anxiety, restlessness and difficulty in concentrating than those who took a placebo, said researcher Neil Edwards of the University of Tennessee.After eight weeks, nine of 12 doxepin users continued to abstain from smoking, compared with only one of 13 on the placebo, according to Edwards, who described the results at a recent American Psychiatric Association meeting.

He undertook the study after three psychiatric patients who took doxepin for depression mentioned they had quit smoking without withdrawal symptoms.

The crucial time for relapse extends for a year after quitting, so studies will have to run at least that long to assess doxepin's effectiveness, Edwards said. Other treatments also have been effective in the short term.

All the subjects had smoked at least five years and averaged 38 cigarettes a day. "They were significant smokers," Edwards said.