Fraser Horton
Fraser Horton
Last Updated on December 24, 2021

People have been consuming marijuana since the time of the ancient civilizations for recreational, medicinal, and spiritual purposes. The main cannabinoids found in weed, THC and CBD, give users psychoactive, sedative, and anti-inflammatory effects. So, it’s no wonder that cannabis is the most used drug around the world according to the UN World Drug Report.

However, despite the wide use of cannabis around the world and its potential health benefits, it’s still classified as a Schedule I drug. In this article, we’ll provide you with all the information about how and when recreational and medical marijuana became illegal, as well as the laws and regulations surrounding marijuana today.

When Was Cannabis Classified as a Schedule I Drug?

Back in the 1970s, US President Richard Nixon was amidst the global campaign known as “The War on Drugs,” which aimed to reduce illegal drug trade in the United States. The campaign focused on preventing problematic drug use, alcohol abuse, as well as drug abuse disorders.

The first step in this fight was the United States Congress passing the Controlled Substances Act (CSA) that became effective on May 1st, 1971. This act classified cannabis as a Schedule I substance under federal law, with a “high potential of abuse and no accepted medical use” along with heroin, ecstasy, and GHB. 

To handle the enforcement of the drug schedule, Nixon established the Drug Enforcement Administration (DEA) with the intent of replacing other federal agencies which carried out anti-drug policies like the Bureau of Narcotics and Dangerous Drugs and the Bureau of Drug Abuse Control.

After the passing of the CSA schedules, some people believed that the prohibition of cannabis should be ended in favor of public health since cannabis has some medical benefits. However, it took a while until new legalization laws were passed in relation to medical cannabis.

The Federal Drug Scheduling System

After Congress passed the Controlled Substance Act, the DEA was responsible for enforcing the drug schedule. While the system has been modified since the ’70s, some of the drugs are still in the same category as they were back then.

This system classifies drugs, substances, and chemicals by scheduling them into 5 categories based on the drug’s acceptable medical use, abuse, and dependency potential. Schedule I drugs have the highest abuse potential, as well as the highest potential for creating a psychological or physical dependence, while Schedule V drugs have the least potential for abuse or dependence.

Schedule I

Schedule I drugs have the highest potential for abuse, no accepted medical use, as well as a high dependency potential. Drugs, substances, and chemicals listed as Schedule I include:

  • Marijuana (cannabis);
  • Heroin;
  • Lysergic acid diethylamide (LSD);
  • Methaqualone;
  • 3,4-methylenedioxymethamphetamine (ecstasy);
  • Peyote.

Schedule II

Schedule II drugs are considered dangerous, have a high potential for abuse, and their use could lead to physical or psychological dependence. Drugs, substances, opioids, and chemicals listed as Schedule II include:

  • Adderall;
  • Ritalin;
  • Dexedrine;
  • Vicodin (less than 15 milligrams of hydrocodone per dosage unit);
  • Methamphetamine;
  • Cocaine;
  • Methadone;
  • Hydromorphone (Dilaudid);
  • Oxycodone (OxyContin);
  • Meperidine (Demerol);
  • Fentanyl.

Schedule III

Schedule III drugs have a moderate to low potential for psychological and physical dependence, and have less abuse potential compared to Schedule I and Schedule II drugs, but more abuse potential than Schedule IV drugs. Drugs, substances, and chemicals listed as Schedule III include:

  • Tylenol with codeine (less than 90 milligrams of codeine per dosage unit);
  • Anabolic steroids;
  • Ketamine;
  • Testosterone.

Schedule IV

Schedule IV drugs have a low potential for abuse and low risk of dependence. Drugs, substances, and chemicals listed as Schedule IV include:

  • Tramadol;
  • Ativan;
  • Soma;
  • Xanax;
  • Darvocet;
  • Talwin;
  • Valium;
  • Ambien;
  • Darvon.

Schedule V

Schedule V drugs have a lower potential for abuse than Schedule IV drugs. They’re generally used for their analgesic, antidiarrheal, and antitussive properties. Drugs, substances, and chemicals listed as Schedule V include:

  • Robitussin with less than 200 milligrams of codeine or per 100 milliliters;
  • Parepectolin;
  • Lyrica;
  • Motofen;
  • Lomotil.

The Controlled Substances Act Today

Marijuana policy has changed a great deal in the past 20 years, although cannabis is still classified as a Schedule I substance on a federal level. When it comes to the classification of substances under the CSA, the Drug Enforcement Administration (DEA) and the Food and Drug Administration (FDA) decide whether a substance needs rescheduling.

At this point, both the DEA and the FDA believe that cannabis should remain classified as a Schedule I drug, and it’s unlikely that this classification will change soon. However, the same doesn’t apply to CBD and CBD products with THC levels under 0.3%. 

After the 2018 Farm Bill was passed into law in December 2018, hemp (Cannabis sativa L.), or derivatives of cannabis with low concentrations of the psychoactive compound THC (under 0.3%), became legal to buy for medical marijuana users.

Medical marijuana users are allowed to use CBD and CBD products by the federal government if they have a medical marijuana card and are under medical supervision of a licensed physician.

Medical Marijuana and State Laws

Marijuana laws have changed federally when it comes to medical marijuana, although not for recreational use of marijuana. While cannabis is still classified as a Schedule I drug, there are differences between federal law and state law when it comes to the use of medical marijuana. Therefore, residents can find it confusing whether to comply with federal laws, or comply with laws that apply on a state level, but violate federal law.

Even though state and federal medical marijuana laws clash in some states, there’s no hesitation that medical cannabis can be used for its “antiepileptic, anxiolytic, antipsychotic, anti-inflammatory, and neuroprotective effects.” In fact, cannabis has been used to treat chronic pain, epilepsy, ADHD, nausea, seizures, appetite loss, anxiety, and other mental health conditions.

As of now, medical use of cannabis has been legalized in 33 states and the District of Columbia, and even more states are considering its legalization, while 15 states and the District of Columbia have already legalized the recreational use of cannabis.

Final Thoughts on Cannabis Classification as a Schedule I Drug

With marijuana legalization being a subject in a lot of media reports and public policy meetings, there’s no telling how much longer cannabis will remain listed as a Schedule I illegal drug in the U.S. 

Its medical use in effectively treating and controlling a wide list of medical conditions is certainly helping to open up more conversation in relation to rescheduling cannabis. 

However, more research is needed for the marijuana federal schedule classification to change from illegal to fully legal, a decision that’s up to the DEA and the FDA. Legalizing it nationwide will mean that cannabis will be as readily available as alcohol – which has only been done in 2 countries around the world.


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