What is a Category 3 controlled substance? An overview

October 10, 2025 •

2 min read

The U.S. Controlled Substances Act of 1970 established a five-tiered system for classifying drugs based on their potential for abuse and medical utility. Among these, understanding what is a Category 3 controlled substance? is crucial for patients and healthcare providers alike, as it represents a significant class of prescription medications with specific regulatory controls.

Quick Summary

An overview of Schedule III controlled substances, explaining their characteristics, medical uses, and regulatory framework under the Drug Enforcement Administration. The article details examples such as certain codeine products, ketamine, and anabolic steroids, clarifying their moderate abuse potential and prescribing limitations.

Key Points

Definition: A Category 3, or Schedule III, controlled substance is a medication with an accepted medical use but a moderate to low potential for physical dependence and a high potential for psychological dependence.
Lower Abuse Risk: The potential for abuse is less than that of Schedule I and II drugs, which include substances like heroin, fentanyl, and cocaine.
Prescription Flexibility: Prescriptions for Category 3 drugs can be verbal, written, or electronic and can be refilled up to five times within six months.
Common Examples: Well-known examples include certain combination products containing codeine, ketamine, and anabolic steroids.
Potential for Misuse: Despite being less potent than Schedule I or II substances, Category 3 drugs carry a risk of misuse and can lead to significant psychological dependence.
Strict Regulation: All pharmacies and practitioners handling these substances must adhere to specific federal recordkeeping requirements to track and prevent diversion.

The Drug Enforcement Administration (DEA) and federal law classify controlled substances into five schedules based on their potential for abuse, accepted medical use, and risk of dependence. Schedule III substances, also known as Category 3, are defined by having a potential for abuse less than Schedule I or II drugs, accepted medical use, and potential for moderate to low physical dependence or high psychological dependence.

Defining a Category 3 Controlled Substance

A Category 3 controlled substance meets several criteria under the Controlled Substances Act, including a lower potential for abuse than Schedule I and II drugs, an accepted medical use, and a dependence risk involving moderate or low physical dependence or high psychological dependence.

Common Examples of Category 3 Drugs

Schedule III includes prescription drugs with medical uses. Examples include codeine combinations with less than 90 mg of codeine per dose, buprenorphine, and ketamine. Anabolic steroids, such as Depo-Testosterone, are also in this category. Recreational use of substances like ketamine is also a concern.

Regulatory and Prescribing Requirements

Regulations for Schedule III drugs aim to prevent diversion while ensuring medical access. Prescriptions can be written, faxed, electronic, or oral, and up to five refills are allowed within six months. Pharmacies and practitioners must keep prescription records for at least two years.

Comparison of Schedule II and Schedule III Controlled Substances

Understanding the differences between Schedule II and III highlights the reasons for their differing regulations.


Feature	Schedule II Controlled Substance	Schedule III Controlled Substance
Abuse Potential	High.	Moderate to low.
Dependence Risk	Severe physical or psychological dependence.	Moderate or low physical, or high psychological dependence.
Accepted Medical Use	Yes, with restrictions.	Yes.
Prescription Refills	Generally not allowed.	Up to 5 within 6 months.
Prescription Method	Mostly written/electronic; emergency oral under strict rules.	Written, electronic, oral, or fax.
Example Drugs	Morphine, fentanyl, oxycodone, cocaine, Adderall.	Tylenol with codeine, ketamine, anabolic steroids.

Potential for Misuse and Side Effects

Category 3 substances, while having lower abuse potential than Schedule II drugs, still pose risks, especially psychological dependence. Misuse can lead to addiction and serious side effects, including mental health issues and organ damage. Examples include liver/kidney damage and mood swings from anabolic steroids, and depression/memory problems from ketamine misuse. Patients must follow prescriptions carefully, and prescribers should monitor usage closely.

Conclusion

A Category 3 controlled substance is a medication with accepted medical use and a moderate risk of abuse and dependence. The DEA's classification system imposes specific rules to balance access and public safety. Though less regulated than Schedule II drugs, Category 3 substances still carry significant risks of dependence and adverse health effects if misused. {Link: DEA.gov https://www.deadiversion.usdoj.gov/schedules/schedules.html} provides further details on the federal classification system. Patient education, careful prescribing, and adherence to regulations are crucial for their safe use.

For further details on the federal classification system, the official U.S. Drug Enforcement Administration website is a valuable resource.

Frequently Asked Questions

The primary difference lies in the potential for abuse and dependence. Schedule II drugs have a high potential for abuse and can lead to severe psychological or physical dependence, whereas Category 3 drugs have a lower potential for abuse and a moderate to low risk of physical dependence.

Yes, prescriptions for Category 3 substances can be refilled. Federal regulations allow for up to five refills within six months from the date the prescription was issued.

Common examples include combination products containing less than 90mg of codeine per dosage unit, ketamine, and anabolic steroids like testosterone.

Abuse of Category 3 drugs can lead to moderate to low physical dependence but a high level of psychological dependence. For example, anabolic steroids are not typically associated with high physical dependence but can cause significant psychological addiction.

Yes, ketamine is classified as a Category 3 controlled substance. It is used medically as an anesthetic but also has potential for misuse due to its dissociative and hallucinogenic effects.

Yes. Pharmacists dispensing Category 3 substances must maintain specific, readily retrievable records for at least two years. They must also document each refill on the prescription or in an electronic record.

Yes, a prescription for a Category 3 controlled substance can be communicated orally (phoned in) by a practitioner to a pharmacist, who must then promptly reduce it to writing.