DEA Controlled Substance Schedules: I to V Chart
Updated
The Controlled Substances Act sorts drugs with abuse potential into five schedules, from Schedule I (the most tightly restricted) down to Schedule V (the least). The PTCE expects you to know what defines each schedule, which drugs are examples, and the prescription and refill rules that follow. This chart lays all of that out in one place, framed for exam recall rather than clinical advice.
Controlled substance law sits in the exam's Federal Requirements domain, which grew to 18.75% of the 2026 PTCE, so it is worth real study time. When you have the schedules down, test yourself with the PTCB federal requirements quiz. This reference is one stop on our PTCB study guide.
How to use this chart on the exam
Learn the schedules as a ladder. Abuse potential falls as the number rises, so Schedule I is the highest risk and Schedule V the lowest, and the refill rules loosen the same way. The single most tested distinction is Schedule I versus Schedule II: both carry a high potential for abuse, but only Schedule II has an accepted medical use, which is why Schedule I drugs cannot be prescribed at all. After that, anchor each schedule to two or three example drugs, because the exam usually asks you to place a named drug rather than recite the legal definition. A handful of numbers do most of the work: Schedule II gets zero refills, Schedule III and IV get up to five refills within six months, and Schedule V cough syrups cap codeine at 200 mg per 100 mL. Finally, keep one golden rule in mind. The PTCE tests federal law only, so answer by the federal rule even when your state is stricter.
The Schedule I to V chart
This is the asset to save. Each row gives the legal definition, the relative abuse potential, and the example drugs the exam draws from.
| Schedule | Definition | Abuse potential | Example drugs |
|---|---|---|---|
| Schedule I | High potential for abuse, no currently accepted medical use in the United States, and a lack of accepted safety for use under medical supervision. | Highest | Heroin, LSD, MDMA (ecstasy), psilocybin, peyote. Marijuana remains Schedule I federally, though a DEA rescheduling proposal is pending. |
| Schedule II / IIN | High potential for abuse, but with a currently accepted medical use. Abuse may lead to severe psychological or physical dependence. | High | Oxycodone, hydrocodone, morphine, fentanyl, hydromorphone, methadone, meperidine; stimulants such as amphetamine (Adderall), methylphenidate (Ritalin), and methamphetamine; cocaine. |
| Schedule III / IIIN | Potential for abuse less than Schedule I and II. Abuse may lead to moderate or low physical dependence and high psychological dependence. | Moderate to low | Products with not more than 90 mg of codeine per dosage unit (Tylenol with Codeine), buprenorphine, ketamine, and anabolic steroids such as testosterone. |
| Schedule IV | Low potential for abuse relative to Schedule III, with a limited risk of dependence. | Low | Alprazolam (Xanax), diazepam (Valium), lorazepam, clonazepam, zolpidem (Ambien), tramadol (Ultram), carisoprodol, phenobarbital. |
| Schedule V | Lowest potential for abuse of the five schedules. Consists primarily of preparations containing limited quantities of certain narcotics. | Lowest | Cough preparations with not more than 200 mg of codeine per 100 mL (Robitussin AC), pregabalin (Lyrica), and diphenoxylate with atropine (Lomotil). |
Prescription and refill rules
The schedule sets the rules for how a prescription may be issued, refilled, and transferred. These federal limits are among the most heavily tested facts in the domain.
| Schedule | Refills | Other federal rules |
|---|---|---|
| Schedule II | No refills permitted | Written or electronic prescription required. Emergency oral fills allowed for the emergency quantity, with a signed written prescription due within 7 days. Ordered from wholesalers on DEA Form 222 or its CSOS equivalent. |
| Schedule III | Up to 5 refills within 6 months of the issue date | May be prescribed in writing, orally, by fax, or electronically. Refill information may be transferred one time only (or up to the maximum refills if the pharmacies share a real-time database). |
| Schedule IV | Up to 5 refills within 6 months of the issue date | Same prescribing and transfer rules as Schedule III. After 5 refills or 6 months, whichever comes first, a new prescription is required. |
| Schedule V | Refilled as authorized by the prescriber | Some Schedule V products may be sold without a prescription where state law permits, subject to limits on quantity, purchaser age, a pharmacist sale, and record keeping. |
Partial fills, forms, and ordering
A few related rules cluster around the schedules and show up often on the exam:
- Ordering Schedule II: a pharmacy orders Schedule I or II stock from a distributor using DEA Form 222 or its electronic CSOS equivalent. Schedule III to V may be ordered on an ordinary invoice.
- Registration: a retail pharmacy registers to dispense controlled substances on DEA Form 224, renewed every 3 years.
- Theft or loss: report to the local DEA field office in writing within one business day, then file DEA Form 106 within 45 days. DEA Form 41 documents destruction, not theft.
- Partial fills of Schedule II:if stock runs short, the remainder is due within 72 hours of the first partial fill. At a patient's request (where state law allows), remaining portions may be filled within 30 days of the issue date.
- Pseudoephedrine (CMEA): not scheduled, but limited to 3.6 g per purchaser per day and 9 g per 30 days, with a logbook kept for at least 2 years.
Frequently asked questions
Which controlled substances cannot be refilled?
Schedule II prescriptions carry no refills under federal law. A new prescription is required each time. Schedule III and IV prescriptions may be refilled up to 5 times within 6 months, and Schedule V may be refilled as the prescriber authorizes.
How many times can a Schedule III or IV prescription be refilled?
Under 21 CFR 1306.22, a Schedule III or IV prescription may be refilled no more than 5 times, and no refill may occur more than 6 months after the issue date, whichever limit comes first.
What is the difference between Schedule I and Schedule II?
Both have a high potential for abuse. The difference is medical use: Schedule II drugs have a currently accepted medical use and can be prescribed, while Schedule I drugs have no accepted medical use and cannot be dispensed for treatment.
Can a Schedule II prescription be phoned in?
Only in a genuine emergency, and only for the quantity needed for the emergency period. The prescriber must then deliver a signed written prescription to the pharmacy within 7 days, or the pharmacist must notify the DEA.
Does the PTCE test state or federal controlled substance law?
Federal law only, because the PTCE is a national exam. Where a state law is stricter, the real-world answer may differ, but on the exam you answer by the federal rule.
Keep studying
Schedules stick once you drill them in exam-style questions. Test your recall with the PTCB federal requirements quiz and read the full Federal Requirements domain guide for the rest of pharmacy law: REMS programs, FDA recall classes, DSCSA, and hazardous handling. For the bigger picture, follow our 2026 PTCB study guide.
Official sources checked
PTCB Quiz Prep is an independent study resource, not affiliated with the Pharmacy Technician Certification Board. This page is exam reference framing based on federal law, not medical or legal advice. See our editorial standards.