As a high school student in the 1970s, he skipped class to smoke, stole money from his parents to support his habit, and scraped his pipe for resin when he didn't have pot to get high.
Today, McCullough, 43, still considers himself an addict. He attends weekly meetings and recognizes if it weren't for treatment, he would have never gotten clean.
"I will always be an addict," said McCullough, now clinical manager at Evergreen Manor, a treatment facility in Everett. "It is something I will have to acknowledge my whole life."
In the aftermath of Washington's legalization of marijuana, critics of the law are pointing to a rarely discussed issue: addiction.
Last year, marijuana use accounted for nearly half of youth admissions to treatment facilities in Washington state, according to data released in October from the Substance Abuse and Mental Health Services Administration. More than 4,200 young people were treated in the state for marijuana use, more than any other drug.
"People are failing to notice that youth use rates are high, availability of marijuana has increased and the perception of harm associated with the drug has dropped," said Dr. Sharon Levy, director of the American Academy of Pediatrics' committee on substance abuse. "These factors have been shown to cause large increases in not only use, but daily use."
Washington's law allows adults 21 and older to possess up to an ounce of marijuana, but drug counselors worry that increased availability will also lead to more underage use. Individuals who start using marijuana at a young age are more likely to become dependent on the drug, according to the National Institute on Drug Abuse.
"It's frightening. We're seeing that the average age of first use has dropped and that more and more kids are using daily," said Levy, who is also an assistant professor of Pediatrics at Harvard Medical School. "I think we're really setting ourselves up for some big problems."
Kevin Oliver, executive director of Washington's National Organization for the Reform of Marijuana Laws (NORML), acknowledged that marijuana dependence can occur if the drug is abused but believes the substance is not addictive enough to pose a significant threat.
"I know users that have no problem consuming cannabis responsibly," Oliver said. "I smoke pot on a regular basis, but I don't let the desire to get high control my life or my actions."
In Snohomish County, more people seek treatment for marijuana addiction than they do for methamphetamine abuse, said Linda Grant, chief executive of Evergreen Manor in Everett.
"I do not think the public is aware of the extent to which marijuana impacts everyday activities," Grant said. "Many patients who come to us arrive for driving under the influence. Other patients arrive knowing they have a problem."
Regardless of the perception of marijuana addiction, treatment statistics are showing growth in marijuana-related problems. In just one month, outpatient admissions for marijuana treatment among Washington state youth increased by 23 percent, growing by 41 new patients from August to September, according to data taken from the Division of Alcohol and Substance Abuse.
Deb Schnellman, spokeswoman for Washington's Division of Behavioral Health and Recovery, said she expects to see an increase in the use of marijuana after its legalization.
"Research shows that when the availability of a substance increases, use goes up as well," Schnellman said.
"The young, developing brain is especially vulnerable to substance use," Schnellman said. "This is why youth are at an increased risk for problems related to drug use."
Levy said tetrahydrocannabinol, or THC, the active ingredient in marijuana, can be addictive.
THC is stored in the user's fat tissue and can linger in the body, so withdrawal symptoms may not be immediately observable.
"Because marijuana dependence looks different than heroin dependence or cocaine dependence, people may be confused into thinking there is no such thing," Levy said.
McCullough recalls sleepless nights filled with discomfort and irritability when he was not able to use the drug. McCullough said he was in a haze while using.
"I didn't think I had a problem because of the effect of the drug," McCullough said. "My ability to rationalize was affected, my whole scope of life was different, I couldn't assess if I was out of control, and I was."
Oliver said he experienced some sleeplessness and irritability when he had to stop consuming marijuana in the past but said it was "no big deal" and didn't "affect his ability to function."
"There is still a social stigma attached to using marijuana that creates a negative view of cannabis being harmful and dangerous," Oliver said. "You can be addicted to anything that causes mental euphoria, sex, gambling, even caffeine. It just depends on the person involved, and if they're in-control or not."
The Murrow News Service provides stories written by journalism students at the Edward R. Murrow College of Communication at Washington State University.
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