James MacWilliams prunes a marijuana plant growing indoors in Portland, Dec. 13, 2017. Credit: Robert F. Bukaty | AP

Medical marijuana sales are down in Maine for the second straight year, a decrease that some dispensary owners blame on unfair competition.

The Portland Press Herald reports tax data shows sales at the state’s eight licensed dispensaries were at $23.5 million in 2018, a 4.1 percent decrease from the previous year.

Medical marijuana dispensary sales peaked at $26.6 million in 2016.

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Dispensary owners say competition from patients growing their own plants or using illegal delivery services has forced them to cut prices.

Maine lawmakers are currently considering new regulations for medical and recreational marijuana that could limit non-dispensary providers.

Voters approved legalizing adult-use marijuana in 2016.

Patricia Rosi, CEO of the dispensary operator Wellness Connection, said the delay in implementing the adult-use program has created “unregulated and illegal competition.”