Republican Gov. Charlie Baker calls the figures "encouraging" but adds there is still much work to do in bringing the epidemic under control.
The state Department of Public Health on Wednesday estimated there were 1,977 opioid-related overdose deaths last year, down 8.3 percent from the 2,155 deaths in 2016.
The previous three years had seen increases of 22 percent, 30 percent and 39 percent, respectively.
While the total number of deadly overdoses declined, the impact of fentanyl continued to grow. Officials say the synthetic opioid was present in toxicology reports in 83 percent of the 2017 deaths.
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