Marijuana Abuse Effects, Signs & Symptoms

Learn about marijuana abuse and substance use disorder

Marijuana, more commonly referred to as “pot,” “grass,” “weed,” “herb,” and “reefer” on the streets, is a greenish mixture of the dried stems, flowers, and shredded leaves of the Cannabis sativa hemp plant. Many individuals use marijuana by smoking joints – rolling this mixture into rolling papers and smoking them like a cigarette. Others use marijuana by smoking the pot using a water pipe called a bong. Blunts, or hollowed out cigars filled with marijuana are another common method of smoking weed. In an effort to reduce the harmful effects of marijuana smoke, many users are beginning to create edibles, or baked goods mixed with marijuana.

THC (Delta-9-tetrahydrocannabinol) is the active ingredient in marijuana that is responsible for the effects of the drug. Smoking marijuana produces the most intense, longest high as the THC quickly passes through the lungs and into the bloodstream, carrying the drug into the body and brain. Once in the brain, THC binds to cannabinoid receptors which are found on the surface of nerve cells found in areas of the brain that influence movement, pleasure, memory, thinking, concentration, coordination, sensory perception, and time perception. CBRs are a component in the endocannabinoid system which plays a vital role in normal brain development and function. THC artificially stimulates the CBRs which disrupts the endogenous cannabinoids, which over time can lead to addiction and withdrawal symptoms when marijuana use ceases.

THC produces its euphoric effects on the user by creating a high by stimulation of dopamine release by neurotransmitters, which can with prolonged abuse lead to damage of the reward pathways of the brain. Marijuana smoke contains a toxic mixture of particulates and gasses, many of which are harmful to the lungs. Chronic marijuana smokers suffer from more respiratory infections in the same way an individual who smokes tobacco does. Also, marijuana smoke has the potential to promote lung cancer and cancers of other areas of the respiratory tract as the smoke is comprised of up to 70% more irritants and carcinogens. As marijuana smokers tend to hold the smoke in their lungs for a longer period of time, the lungs are exposed to higher concentrations of this noxious smoke.

The most commonly used illicit drug, the heaviest marijuana users are young adults and adolescents. Long-term marijuana usage can lead to addiction; or the inability of an individual to stop the drug usage despite the negative consequences the drug use has upon his or her life.

Marijuana abuse statistics

According to the 2010 National Survey on Drug Use and Health, 17.4 million individuals smoked within the past month. That year, marijuana was used by 76.8% of illicit drug users and was the only drug used by 60.1% of them.

It’s estimated that 9% of marijuana users will become dependent upon marijuana; that jumps to 1 in 6 of those who begin using marijuana in their teen years.

Causes and risk factors for marijuana abuse

Researchers have yet to determine what precisely leads to addiction; it’s generally thought that the development of an addiction is caused by a number of factors working together. These include:

Genetic: Many individuals who have a first-degree relative, such as a parent or sibling who struggles with addiction will also go onto develop an addiction later in life. While not a definitive indicator, it is a prognostic indicator of future addiction.

Biological: It’s been postulated that certain individuals may be born lacking cannabinoid receptors in the brain and may smoke pot in order to correct these inborn deficiencies. While not in the statistical majority, it is a possibility for the development of a marijuana addiction.

Environmental: Individuals who are born into a distressed home environment are more likely to develop an addiction later in life. In addition, individuals who begin to abuse drugs at an earlier age are more prone to develop an addiction.

Psychological: Many individuals struggle with undiagnosed mental illnesses and may attempt to self-medicate their symptoms away through the usage of drugs and alcohol. Unfortunately, this only serves to worsen the effects of mental health and emotional well-being.

Signs and symptoms of marijuana abuse

Symptoms of marijuana addiction occur on a spectrum depending upon the length of abuse, the amount of marijuana used, and the frequency in which an individual abuses marijuana.

Mood symptoms:

• Relaxed
• Sense of well-being
• Anxiety
• Depression
• Mood swings
• Fear
• Panic attacks

Behavioral symptoms:

• Problems with memory and concentration
• Laughter
• Sleepiness
• Inability to properly carry out complex tasks such as driving
• Impairment in ability to form new memories
• Distinctive marijuana smoke smell in clothing
• Appears high or spaced out
• Slowed reflexes
• Increased appetite – “the munchies”
• Slowed response time
• Impaired coordination
• Slowed speech
• Abnormal patterns of speech – jumping from one topic to the next without properly finishing a thought

Physical symptoms:

• Upper respiratory infections
• Hypertension
• Increased risk for cancer
• Weight gain
• Tachycardia
• Red, watery eyes

Psychological symptoms:

• Worsening symptoms of mental illnesses
• Heightened sensory perception
• Altered time perception
• Distrust
• Impaired short-term memory
• Lapses in memory
• Psychotic episodes
• Hallucinations
• Delusions
• Loss of sense of personal identity

Effects of marijuana abuse

The long-term effects of chronic marijuana usage will vary depending upon the amount used, the length of use, and the method of abuse. Effects of long-term marijuana usage include:

• Addiction
• Impaired memory
• Impaired ability to learn
• Reduced intellectual level
• Sleep problems
• Chronic upper respiratory infections
• Increases risks for development of schizophrenia
• May increase risks for depression, anxiety, and amotivational syndrome

Marijuana abuse & Co-Occurring disorders

Many individuals who struggle with marijuana addiction are suffering from undiagnosed mental health disorders. These include:

• Other addictions
• Alcoholism
• Bipolar disorder
• Depressive disorders
• Anxiety disorders
• Schizophrenia

Effects of marijuana withdrawal and overdose

While marijuana isn’t a particularly addictive substance – addiction to caffeine is more common – dependence upon marijuana is more common among those who are heavy users. Withdrawal symptoms for those who decide to stop using pot after long-term chronic usage include:

• Insomnia
• Restlessness
• Decreased appetite
• Irritability
• Anger
• Depression