Table of ContentsView AllTable of ContentsHistoryHow It WorksFormsUsesPotential PitfallsHow to Get Help
Table of ContentsView All
View All
Table of Contents
History
How It Works
Forms
Uses
Potential Pitfalls
How to Get Help
What is the most important information I should know about THC?THC affects the brain’s reward system and can lead to addiction. Treatments are available that can help.Although state laws may vary, products containing more than 0.3% THC are illegal according to federal law.
What is the most important information I should know about THC?
THC affects the brain’s reward system and can lead to addiction. Treatments are available that can help.Although state laws may vary, products containing more than 0.3% THC are illegal according to federal law.
THC is just one of more than 500 different substances—and 100different cannabinoidmolecules—in marijuana.Although THC is the most recognized, another important cannabinoid molecule that has received major interest iscannabidiol(CBD).
Marijuana can be addictive, so it is important to be aware of the effects and risks of THC. This article discusses what you need to know about the effects of THC, its potential medicinal uses, and the risks of substances that contain THC.
History of THC
Cannabis has a long history of use that dates back thousands of years. The first recorded use of cannabis has been traced to China, where it was used for food, textiles, and medicine. Hemp was eventually introduced to Europe and later to the Americas, where it was used for both recreational and ritual purposes.
Cannabis was introduced to what is now the United States during the 1600s. Hemp was grown to produce textiles and sometimes even used as legal tender. It was used for a number of medical purposes as well, with itsrecreational usebeginning to grow during the 1930s and 1940s.
Around this time, anti-drug campaigns were instituted against its use and many states passed laws prohibiting marijuana. The 1936 film “Reefer Madness” portrayed marijuana as a dangerous drug that led to psychosis, violence, and suicide.
In 1970, the Controlled Substances Act classified marijuana as aSchedule I drug, identifying it as having a high potential for abuse and making the drug illegal at the federal level. The “war on drugs” launched during the 1970s led to the large-scale incarceration of many people for marijuana possession and use.
Statistics suggest that the enforcement and penalization of marijuana laws disproportionately target people of color. While drug use has similar rates for people of all racial and ethnic backgrounds, Black and Latinx people are far more likely to be arrested and jailed for drug offenses.
While it is still not legal at the federal level, many states have approved the use of cannabis and THC for medical and, in some states, recreational purposes. Always check state laws before purchasing any products containing THC.
In 2024, the U.S. Drug Enforcement Administration (DEA) indicated that they intend to reclassify marijuana as a Schedule III drug.This rescheduling will recognize that cannabis has legitimate medical purposes and will help open the door to research on other potential treatment uses. It also continues to recognize that marijuana still has a risk for dependence and abuse while acknowledging that this potential is less than it is for Schedule I drugs.
However, it is important to note that this will not legalize marijuana for recreational use. Even after rescheduling, marijuana will continue to be illegal at the federal level.
THC Mechanism of Action
Because of this reward system activation, the brain learns to repeat the rewarding behaviors that lead to pleasant feelings. This is what contributes to the addictive properties of THC.
Using higher amounts of THC for longer periods of time increases this risk for addiction.
5 Signs of Marijuana (Weed) Addiction
Forms of THC
Inhalation
This is the fastest method of administration and produces effects within minutes. Research suggests that people who use medical cannabis for pain relief prefer this method of administration because it produces the fastest results.
Recent reports suggest thatvaping THC oilmay pose serious and potentially fatal safety risks.The CDC and FDA both recommend avoiding all vaping an e-cigarette produces, particularly those that use THC oil.
Oral Ingestion
Marinol (dronabinol) is a cannabis-derived medication that is FDA-approved to treat anorexia associated with weight loss in patients with AIDS and nausea and vomiting associated with chemotherapy in patients who have not responded to other antiemetics. Marinol is available in an oral capsule form.
Syndros (dronabinol) is another cannabis-derived medication that is FDA-approved to treat nausea, vomiting, and loss of appetite in people who have AIDS or who are undergoing chemotherapy. It is available as a liquid solution.
Topical Application
THC can also be included in lotions, balms, salves, oils, and bath salts applied to the skin. These methods usually have localized effects, which means that they are unlikely to have psychoactive effects. However, such products may help reduce pain and inflammation.
Sublingual Administration
THC can also be consumed as lozenges, sprays, or dissolvable strips that are placed under the tongue and dissolved.
While many states permit some forms of THC under different circumstances, federal law prohibits the possession, use, and sale of cannabis products containing more than 0.3% THC.
THC in CBD Products
With the popularity of CBD, there has been a major market shift toward producing a seemingly endless variety of CBD products. Some of these products may contain traces of THC (around 0.3% to 0.9%), depending on how they’re formulated.
Research indicates that many CBD products contain more THC than their labels suggest. In one study, 70% of CBD products were mislabeled and contained more THC than indicated on the label.Such products are not regulated, so it can be difficult to tell how much THC they actually contain.
However, if you’re looking for a CBD product without any THC, be sure to select one that uses third-party testing to certify the purity of the product.
According to the FDA, THC and CBD cannot be legally sold as dietary supplements. Be sure to check your state’s laws to determine if such products are legally available in your state.
CBD vs. THC: What’s the Difference?
Uses for THC
THC has a number of medicinal uses. Marijuana has been used for medicinal purposes for thousands of years, although scientific research on its use to alleviate and treat illness is still relatively recent.
According to the National Center for Complementary and Integrative Health, a division of the National Institutes of Health, some of the mental health conditions that THC may help include:
There are currently no FDA-approved THC medications to treat mental health conditions.
Potential Pitfalls of THC
There is considerable research-based evidence that THC is associated with anincreased risk of psychosis, bothamong adolescentsand adults.It is also linked to increased anxiety, learning impairment, and decreased memory formation.
CBD has been found to help counter these effects,reducing anxiety, improving learning ability, and working as an antipsychotic—although much of the available research is on animals.When taken together, as is the case with marijuana use, CBD seems to reduce the negative effects of THC.
One meta-analysis, which is a type of study that looks at the results of many previous studies, also found some evidence that THC may be neurotoxic as there are differences in the brain structure of people who regularly use marijuana (and who do not havepsychosis).
One interesting point underscoring brain changes: While research has shown a reduction in gray matter volume in the prefrontal cortex of people with a history of heavy marijuana use, there is an apparent compensatory response. The density of fibrous connections among remaining neurons increases, which may cancel out some or all of the neurotoxicity.
Effects of Heavy Marijuana Use
Is Delta-9 THC Addictive?
Cannabis is the most commonly used federally illegal substance in the United States.Despite the common belief that the drug is not addictive, THC tolerance and dependence (precursors to addiction) have been widely documented.
According to the National Institute on Drug Abuse (NIDA), about 30% of people who use marijuana will become addicted—and using the drug prior to age 18, when the brain is still developing, increases the likelihood ofcannabis use disorderfour- to seven-fold.
Similar to other types of addiction, cannabis use disorder involves a preoccupation with the drug, bingeing, andsymptoms of withdrawalwhen it cannot be used. Additional criteria for diagnosing an addiction include experiencing constant cravings and having drug-related relationship and social issues.
How to Recognize the Symptoms of Marijuana Addiction
Amount of THC in Marijuana
Americans are definitely not dealing with the same THC products as in the past. This is because today’s marijuana is much more potent, with THC concentration levels increasing from 9.75% in 2009 to 13.88% in 2019.
For comparison purposes, the THC content of marijuana back in the 1960s, 1970s, and 1980s was under 2%, increasing to around 4% in the 1990s. Additionally, some strains today have an even higher content, including some that contain as much as 28% THC.
The Different Types of Cannabis
If you or a loved one wants to stop using THC but are finding this difficult, several options exist. Treatments for cannabis use disorder that show promise for providing positive results include:
While some suggest that drugs such asselective serotonin reuptake inhibitors(SSRIs) andanxiolytics(anti-anxiety medications) may help treat cannabis use disorder, evidence is lacking due to small study sizes and varying methods of assessing treatment outcomes.
If you or a loved one are struggling with substance use or addiction, contact theSubstance Abuse and Mental Health Services Administration (SAMHSA) National Helplineat1-800-662-4357for information on support and treatment facilities in your area.For more mental health resources, see ourNational Helpline Database.
If you or a loved one are struggling with substance use or addiction, contact theSubstance Abuse and Mental Health Services Administration (SAMHSA) National Helplineat1-800-662-4357for information on support and treatment facilities in your area.
For more mental health resources, see ourNational Helpline Database.
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Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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