The DEA’s drug schedule organizes drugs into groups based on risk of abuse or harm. Those drugs with high risk and no counterbalancing benefit are banned from medical practice and are Schedule I drugs. Conversely, those considered to have the lowest risk would be in Schedule V (5). A drug or chemical can be treated as a Schedule 1 substance for criminal prosecution even if it is not a controlled substance.
Controlled drugs that are considered to have virtually no risk for addiction, abuse or harm are not scheduled. Examples of those would be insulin, blood pressure and cholesterol medicines.
Often searched for are: Ketamine (schedule 3), tramadol (schedule 4), weed/marijuana/pot (schedule 5 though uncontrolled/legal in some states). Lyrica/pregabalin (schedule 5). Both Propofol and Gabapentin remain unscheduled in the US, meaning you need a prescription(they are controlled), but it’s not a scheduled substance.
In 1970 the FDA released the following drug classifications, or drug schedules, under the Controlled Substance Act (CSA).
Drug Schedule I Controlled Substances
Schedule I drugs have no currently accepted medical use and aren’t considered safe to use even under medical supervision. They have a high potential for abuse and dependency.
Marijuana falls into Schedule I. The Controlled Substances Act was passed in 1970, at a time when there was a “war on drugs” and the concept of zero tolerance and pot as a gateway drug was mainstream thinking. One of the many unintended consequences of slotting marijuana into Schedule I was the restrictions it placed on the ability to conduct research to discover if and what are the “medicinal” properties of marijuana and what are the dangers. Without good, or even reasonable quality research, the discussions of legalizing marijuana are based on opinion, not fact. MedShadow discusses the unreasonable requirements put on marijuana researchers in this video.
Other Schedule I drugs are: heroin, LSD (lysergic acid diethylamide), marijuana (cannabis), peyote, methaqualone, and Ecstasy (3,4-methylenedioxymethamphetamine).
Drug Schedule II/IIN Controlled Substances (2/2N)
This category is for drugs that have a high potential for abuse which may lead to severe psychological or physical dependence. Drug Schedule II/IIN substances are considered to have medical value.
Examples of Schedule II controlled drugs include: OxyContin and Percocet (oxycodone), opium, codeine, morphine, hydromorphone (Dilaudid), methadone, Demerol (meperidine), and fentanyl.
Examples of Schedule IIN stimulants include: amphetamine (Dexedrine, Adderall), methamphetamine (Desoxyn), and methylphenidate (Ritalin).
Drug Schedule III/IIIN Controlled Substances (3/3N)
The potential for abuse for Schedule III/IIIN medicines is less than substances in drugs classified as Schedule I or II/IIN and abuse may lead to moderate or low physical dependence or high psychological dependence.
Examples of Schedule III narcotics include: Ketamine, Vicodin (combination products containing less than 15 milligrams of hydrocodone per dosage unit), Tylenol with Codeine (products containing not more than 90 milligrams of codeine per dosage unit), and buprenorphine (Suboxone).
Examples of Schedule IIIN non-narcotics include anabolic steroids such as Depo-Testosterone.
Drug Schedule IV Controlled Substances
The medicines in drug classification Schedule IV /Schedule 4 can and are abused and can be addictive or create a dependency, but less than those of Schedules 1, 2 and 3.
Examples of Schedule IV substances include: Tramadol, Xanax (alprazolam), carisoprodol (Soma), Klonopin (clonazepam), Valium (diazepam), Ativan (lorazepam (Ativan).
Drug Schedule V Controlled Substances
These drugs are considered to have a low potential for abuse relative to substances listed in Schedule IV and consist primarily of preparations containing limited quantities of certain narcotics.
Examples of Schedule V drugs: Lyrica/pregabalin, cough preparations containing not more than 200 milligrams of codeine per 100 milliliters or per 100 grams (Robitussin AC, Phenergan with Codeine), and ezogabine.
For more information and a complete list of substances: Drug Enforcement Administration Office of Diversion Control.