What do Alaska, Colorado, Oregon, Washington, D.C., and the state of Washington have in common? They've all legalized recreational marijuana use for adults.

In addition, a total of 24 states now allow medical marijuana in various ways. In New York, you cannot smoke it, although you can inhale a vapor, eat it, use a tincture or take pills. More than 12 states have decriminalized possession altogether.

No wonder marijuana use more than doubled from 2001 to 2013.

Unfortunately, according to a study in JAMA Psychiatry, in 2012-2013 nearly 30 percent of users had marijuana use disorder, otherwise known as MUD. That's a huge percentage.

Symptoms include problems with normal functioning, cravings and withdrawal issues such as inability to sleep, restlessness, nervousness, anger or depression within a week of ceasing heavy use.

There are also neurocognitive and psychiatric repercussions of MUD, especially in young people and young adults.

When researchers at Columbia University Medical Center looked at the brains of folks who started smoking cannabis at 16, became dependent by 20 and have been dependent for the past seven years, they found that compared with nonsmokers they had lower dopamine release in brain areas that affect learning and working memory tasks.

The depression associated with withdrawal is also a likely result of alterations in dopamine availability.

Don't get stuck in the MUD; if you or someone you love needs help with marijuana dependence, go to www.findtreatment.samhsa.gov to get started creating a healthier, happier future.