Legal Sidebari

An Expiration Date for Temporary Control of
Fentanyl Analogues
Updated April 6, 2021
In February 2020, the Temporary Reauthorization and Study of the Emergency Scheduling of Fentanyl
Analogues Act (the Act) temporarily placed certain fentanyl analogues—i.e., compounds chemically
related to the powerful synthetic opioid fentanyl—on Schedule I of the Controlled Substances Act (CSA).
The temporary scheduling of fentanyl analogues under the Act is slated to expire on May 6, 2021. In light
of the approaching expiration, Congress may be interested in the legal issues related to the scheduling of
fentanyl analogues. This Sidebar provides an overview of the legal framework that applies to fentanyl and
its analogues, key considerations involved in scheduling fentanyl analogues, and options for pursuing
scheduling via legislation.
The CSA and Controlled Substance Regulation
The CSA regulates drugs and other substances—whether medical or recreational, legally or illicitly
distributed—that pose a risk of abuse and dependence. Substances become subject to the CSA through
classification into one of five lists, known as Schedules I through V. Controlled substances in Schedule I
are subject to the most stringent controls, reflecting a finding that a substance has a high potential for
abuse and no currently accepted medical use. Substances in Schedules II through V have accepted
medical uses and have been deemed to pose progressively lower risks of abuse and dependence.
Fentanyl itself is in Schedule II, as it has recognized medical uses such as pain management for cancer
patients and individuals on ventilators. Multiple nonpharmaceutical substances chemically related to
fentanyl are controlled in Schedule I. By contrast, cough medicines containing limited amounts of another
opiate, codeine, are in Schedule V. (Many other prescription drugs are not controlled substances subject to
the CSA.)
A substance not specifically designated for control in Schedules I through V may still be subject to the
CSA as a controlled substance analogue. A controlled substance analogue is a substance not otherwise
approved by the Food and Drug Administration (FDA) or scheduled under the CSA that has (1) a
chemical structure substantially similar to that of a controlled substance in Schedule I or II, or (2) an
actual or intended effect that is “substantially similar to or greater than the stimulant, depressant, or
hallucinogenic effect . . . of a controlled substance in schedule I or II.” A substance that meets those
criteria and is intended for human consumption is treated as a controlled substance in Schedule I.
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Unscheduled synthetic opioids related to fentanyl may qualify as controlled substance analogues.
However, as a practical matter, treating those substances as controlled substance analogues may allow for
less effective control than if the substances are specifically scheduled under the CSA. The Department of
Justice (DOJ), which prosecutes CSA violations, has stated that controlled substance analogue
prosecutions are fact-intensive and burdensome compared to prosecutions involving scheduled substances
because analogue cases raise “complex chemical and scientific issues” related to the molecular makeup
and effect of each substance. Moreover, some synthetic drugs may not meet the applicable criteria to be
deemed controlled substance analogues—for example, because their effects are unpredictable or because
they replicate the effects of more than one class of drugs. As a result, some policymakers have expressed
interest in formally scheduling fentanyl analogues.
Administrative and Legislative Scheduling Procedures
Either Congress or the Drug Enforcement Administration (DEA) Administrator can place a substance in a
CSA schedule, move a substance to a different schedule, or remove a substance from a schedule.
Congress can take those scheduling actions through legislation. DEA, for its part, makes permanent
scheduling decisions through a complex administrative process that involves participation by other
agencies and the public. Before initiating scheduling proceedings, DEA must request a scientific and
medical evaluation of the substance at issue. FDA prepares the evaluation and must consider eight
statutory factors primarily related to the effects of the substance and its potential for abuse. Based on
those factors, FDA recommends whether the substance should be controlled and, if so, in what schedule.
FDA’s scientific and medical factual findings are binding on DEA, and if FDA recommends against
controlling the substance, DEA cannot schedule it.
Upon receipt of FDA’s report, the DEA Administrator evaluates all the relevant data and determines
whether the substance should be scheduled, rescheduled, or removed from control. Before placing a
substance in a schedule, the DEA Administrator must make specific findings related to the substance’s
medical use and potential for abuse and dependence. DEA makes scheduling decisions through notice-
and-comment rulemaking, meaning that interested parties must have the opportunity to submit comments,
which the agency may need to respond to before the scheduling action becomes final. Once final, DEA
scheduling decisions are subject to judicial review.
Permanent DEA scheduling decisions can take years to consider and finalize. Recognizing that in some
cases faster scheduling may be appropriate, Congress also created a temporary scheduling procedure,
allowing the DEA Administrator to place a substance in Schedule I temporarily when “necessary to avoid
an imminent hazard to the public safety.” Before issuing a temporary scheduling order, the DEA
Administrator must provide 30 days’ notice to the public and the Secretary of Health and Human Services
(HHS) and consider any comments from the Secretary. In issuing a temporary scheduling order, the DEA
Administrator needs to consider only three of the eight factors relevant to permanent scheduling: (1) the
history and current pattern of abuse of the substance at issue; (2) the scope, duration, and significance of
abuse; and (3) the risk to the public health. A substance may be temporarily scheduled for up to two years.
If permanent scheduling proceedings are pending, the DEA Administrator may extend the temporary
scheduling period for one additional year. Temporary scheduling orders are not subject to judicial review.
Temporary Scheduling of Fentanyl-Related Substances
On February 6, 2018, DEA issued a temporary scheduling order (Fentanyl TSO) that placed certain
“fentanyl-related substances” in Schedule I for two years. While previous scheduling actions by both
DEA and Congress identified a specific substance or a list of several discrete substances for control, the
Fentanyl TSO instead imposed controls on a broad class of “fentanyl-related substances” that met specific
criteria related to their chemical structure. While that class of substances is finite, it includes thousands of

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different chemicals. As one opioid researcher testified before Congress, the effects, potential for abuse
and dependence, and medical utility of many of those substances are unknown.
Perhaps because of these uncertainties, DEA did not initiate permanent scheduling of the class of
substances subject to the Fentanyl TSO. January 2020 testimony from HHS suggested that, given the
large number of substances subject to the order, it was simply not feasible for FDA and DEA to make the
individualized findings required to permanently schedule each substance. Without such findings,
administrative action to permanently schedule the full class of fentanyl-related substances could be
vulnerable to challenge in court. Accordingly, stakeholders including DEA and HHS
https://docs.house.gov/meetings/JU/JU08/20200128/110392/HHRG-116-JU08-Wstate-GiroirB-
20200128.pdfcalled on Congress to permanently schedule that class of substances through legislation.
(In the meantime, DEA has continued to take temporary and permanent scheduling actions with respect to
certain specific fentanyl analogues, including some fentanyl-related substances subject to the Fentanyl
TSO.)
On February 6, 2020, in response to calls for legislative scheduling, Congress enacted the Temporary
Reauthorization and Study of the Emergency Scheduling of Fentanyl Analogues Act. However, that
legislation did not permanently schedule the substances that were the subject of the Fentanyl TSO.
Instead, the Act temporarily extended the Fentanyl TSO until May 6, 2021. Absent further legislative or
administrative action, the class of “fentanyl-related substances” will remain in Schedule I until that date,
and will be subject to all restrictions and penalties applicable to Schedule I substances. If the Act expires,
the full class of substances at issue will no longer be scheduled under the CSA, though they may still be
subject to control as controlled substance analogues. Fentanyl itself and certain other related chemicals
are permanently controlled in Schedules I and II; the Act does not affect those classifications.
Considerations for Congress
If Congress pursues permanent scheduling of fentanyl analogues, several legal questions may arise.
Defining Substances Subject to Control
A key question when scheduling fentanyl analogues is how to define the substances subject to regulation.
Not all fentanyl analogues have effects like those of fentanyl itself, and there are many whose effects are
unknown. As discussed above, the Fentanyl TSO, which the Act extended, defines covered substances
based on their chemical structure. Some have argued that this legal definition may be both overinclusive
(because it may include inactive substances) and underinclusive (because it may exclude potentially
dangerous opioids that are not chemically related to fentanyl or that involve chemical modifications not
listed in the Fentanyl TSO). In light of those concerns, the Act required the Comptroller General to
conduct a study evaluating the Fentanyl TSO’s definition of substances subject to control. As of the date
of this Legal Sidebar, that study has not yet been published.
Addressing fentanyl analogues by using the Fentanyl TSO’s definition of “fentanyl-related substances” is
not the only option for Congress. Proposals in the 116th Congress would have taken differing approaches
to scheduling fentanyl analogues. For instance, the Stopping Overdoses of Fentanyl Analogues Act would
have permanently added to Schedule I certain specific fentanyl analogues, as well as the class of
“fentanyl-related substances” defined in the Fentanyl TSO. The Modernizing Drug Enforcement Act of
2019 would have amended the CSA to add to Schedule I “mu opioid receptor agonists”—a class of
opioids (including morphine) that is defined by the molecular reactions that produce their effects. The
SIFT Act of 2019 would have scheduled certain specific fentanyl analogues, as well as the class of
“fentanyl-related substances” defined in the Fentanyl TSO, and would also have provided a process for
expedited descheduling of any fentanyl-related substances that were later found to pose little or no risk of
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Criminal Enforcement and Sentencing
Another question related to the scheduling of fentanyl analogues is how those substances should fit into
the CSA’s criminal enforcement and sentencing regimes. Penalties for criminal violations of the CSA
vary widely based on the substance at issue, with some penalties tailored to specific substances. Sentences
also depend on numerous other factors, including the amount of the substance involved and the nature of
the illicit activity (e.g., simple possession versus distribution). The CSA imposes mandatory minimum
sentences for some offenses involving Schedule I controlled substances. No mandatory minimum penalty
attaches to a first conviction for simple possession or manufacture, distribution, and possession with
intent to distribute most Schedule I controlled substances; however, minimum sentences apply to second
and subsequent offenses and offenses resulting in death or serious injury. And, under CSA provisions that
predate the Act, mandatory minimum sentences apply to the manufacture, distribution, and possession
with intent to distribute large amounts of fentanyl or “any analogue” of fentanyl.
As for the mental state required to produce criminal liability, the CSA generally applies to offenses
committed knowingly or intentionally. The Supreme Court has explained that prosecutors bringing
charges under the CSA must prove that a defendant either knew he was dealing with “some unspecified
substance listed on the federal drug schedules” or “knew the identity of the substance he possessed.” For
example, “a defendant who knows he is distributing heroin but does not know that heroin is listed on the
schedules” satisfies the CSA’s mental state requirement.
Applying these rules to legislation scheduling a class of fentanyl analogues raises a number of legal and
policy issues. Some commentators have raised criminal justice concerns, asserting that individuals may
face criminal liability for unwitting possession of fentanyl analogues, or that Schedule I status may give
rise to harsh mandatory minimum penalties under the CSA. On the other hand, some commentators and
law enforcement officials seek more stringent controls of fentanyl analogues to combat the opioid crisis.
As discussed above, difficulties in prosecuting activities involving unscheduled fentanyl analogues under
the analogue controlled substance provisions of the CSA have led to calls for permanently placing
fentanyl-related substances in Schedule I. While the Fentanyl TSO and the Act temporarily controlled
fentanyl-related substances in Schedule I, neither altered the CSA’s sentencing regime or the mental state
requirements that apply to controlled substance offenses. A January 2021 U.S. Sentencing Commission
report examines in detail recent sentencing practices related to fentanyl and fentanyl analogues.
Proposals in the 116th and 117th Congresses would tailor how the CSA applies to fentanyl analogues. For
instance, the Federal Initiative to Guarantee Health by Targeting Fentanyl Act would permanently
schedule a class of fentanyl-related substances but provide that certain minimum terms of imprisonment
do not apply to those substances. By contrast, the Ending the Fentanyl Crisis Act of 2019 would have
applied more stringent control to fentanyl analogues, imposing penalties for “scheduled or unscheduled”
fentanyl analogues and reducing the amounts of those substances required to trigger mandatory sentences.
Research Access
While fentanyl analogues may pose public health risks, some commentators contend that the substances
may also offer medical benefits—including pain management and treatment of opioid dependence or
overdose—and worry that placing fentanyl analogues in Schedule I may impede research into potential
medical uses.
Although people sometimes colloquially refer to substances in Schedule I as “illegal drugs,” the CSA
does not fully ban any drugs or other substances. Schedule I controlled substances have no accepted
medical use and thus may not be dispensed by prescription like other controlled substances. Nonetheless,
it is legal to produce, dispense, and possess Schedule I substances in the context of federally approved
scientific studies. At the same time, Schedule I status creates certain legal hurdles for would-be
researchers. For example, those who conduct research with controlled substances must comply with the

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CSA’s registration requirements, which include security and reporting obligations. In addition, a rider to
the appropriations bill for FY2021 provides that, subject to certain exceptions, no federal funds may be
used for any activity that “promotes the legalization” of a Schedule I controlled substance. The
appropriations rider does not directly restrict research involving Schedule I controlled substances; it
simply limits the availability of federal funding to support such research. No court has interpreted the
rider, however, and it is not clear whether “legalization” only includes federal descheduling or extends to
moving a substance to a less restrictive CSA schedule or state decriminalization.
The Temporary Reauthorization and Study of the Emergency Scheduling of Fentanyl Analogues Act
required the Comptroller General to report on the status of research on fentanyl analogues. In addition,
there were a number of proposals in the 116th Congress to substantively alter the legal framework for
research involving Schedule I controlled substances. For example, the SIFT Act of 2019 would have
relaxed certain registration requirements that apply to research on Schedule I controlled substances. And a
proposed amendment to the appropriations bill for FY2020 would have eliminated the appropriations
rider limiting federal funding for Schedule I research.

Author Information

Joanna R. Lampe

Legislative Attorney




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