DEA/OD/ODE page 1 of 10 April 27, 2015

Acetyl Fentanyl

Background Information and Evaluation of ‘Three Factor Analysis’ (Factors 4, 5 

and 6) for Temporary Scheduling

Drug and Chemical Evaluation Section, Office of Diversion Control, Drug Enforcement 

Administration, 8701 Morrissette Drive, Springfield, VA 22152

April 2015

Introduction

N-(1-phenethylpiperidin-4-yl)-N-phenylacetamide (acetyl fentanyl) is a potent 

opioid analgesic and has no accepted medical use in the United States. Since 2013, both 

law enforcement and public health reports demonstrate the illicit use and distribution of 

this substance. Reports indicate that acetyl fentanyl is available on the illicit market as a 

powder or in tablet form which mimic pharmaceutical opiate products. In powder form, 

the identity of the substance may go unknown to the end user as it may be marketed as 

heroin or mixed with heroin. Recent reports indicate that acetyl fentanyl is available over 

the Internet.

Acetyl fentanyl was first mentioned in a book chapter in 1968 by Janssen and Van 

der Eycken. It exhibits a typical morphine-like profile in animals. Data show that the 

analgesic potency of acetyl fentanyl is up to 15.7 times greater than that of morphine in 

mice as evaluated using an acetic acid writhing method (Higashikawa and Suzuki, 2008).

Since 2013, adverse effects due to acetyl fentanyl toxicity have been reported in humans. 

Similar to other opioids (i.e. heroin, oxycodone, hydrocodone, fentanyl, etc.), acetyl 

fentanyl induces respiratory depression which may lead to death in an overdose event. 

DEA is currently aware of 39 confirmed fatalities in which acetyl fentanyl was a 

contributing factor. These fatalities occurred in California (1), Louisiana (14), North 

Carolina (7), Oregon (1), Pennsylvania (1) and Rhode Island (15). The extent of abuse 

and mortality associated with acetyl fentanyl is likely to be underestimated since it is not 

included in most drug screens. In addition, the identity of fentanyl and acetyl fentanyl 

cannot be distinguished by commonly used drug screens including enzyme-linked 

immunosorbent assay (ELISA). Further confirmatory testing (i.e. mass spectrometry) is 

required to identify acetyl fentanyl (CDC, 2013). 

Reports of overdose and fatalities associated with abuse of acetyl fentanyl have 

been recorded. The Rhode Island Department of Health reported 15 fatalities associated 

with acetyl fentanyl in 2013. The ages of the decedents ranged from 19 to 57 years.

Acetyl fentanyl was involved in seven fatalities in North Carolina in 2014. Two fatal 

overdoses and one death associated with acetyl fentanyl were reported from St. Tammany 

Parish, Louisiana in 2014 and one fatal overdose was reported in Oregon in September 

2014. Eleven overdose deaths involving acetyl fentanyl have been reported from 
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Jefferson Parish, Louisiana in 2013 and 2014. San Diego County, California reported 

one death due to acute acetyl fentanyl intoxication in November 2014. 

With no legitimate medical use and limited pharmacological information, acetyl 

fentanyl has emerged on the illicit drug market and is being abused for its opioid

properties. To protect the public health and safety, the Drug Enforcement Administration 

(DEA) is temporarily placing acetyl fentanyl in Schedule I of the Controlled Substances 

Act (CSA). With respect to finding an imminent hazard to the public safety, DEA has 

considered the three factors required under the CSA for the temporary scheduling of 

acetyl fentanyl. 21 U.S.C. 811(h)(3) and 811(c)(4)-(6).

Acetyl Fentanyl

 Fentanyl Acetyl Fentanyl

Figure 1. Chemical Structures of Fentanyl and Acetyl Fentanyl

Acetyl fentanyl is a synthetic opioid in the phenylpiperidine class which includes 

fentanyl. Acetyl fentanyl differs in chemical structure from fentanyl by one carbon atom 

and two hydrogen atoms. Fentanyl possesses a phenyl propanamide functionality 

whereas acetyl fentanyl has a phenyl acetamide group (Figure 1). Acetyl fentanyl has also 

been referred to as desmethyl fentanyl, likely due to the removal of a methylene group 

from the chemical structure of fentanyl.

Factor 4. History and Current Pattern of Abuse 

Clandestinely produced substances structurally related to the Schedule II opioid

analgesic fentanyl, were trafficked and abused on the West Coast in the late 1970s and 

1980s. Alpha-methylfentanyl, the first fentanyl analogue identified in California, was 
DEA/OD/ODE page 3 of 10 April 27, 2015

placed into Schedule I of the CSA in September 1981. Following the control of alphamethylfentanyl, DEA identified several other fentanyl analogues (See Appendix A) in 

submissions to forensic laboratories. These substances were temporarily controlled under 

the CSA after finding that they posed an imminent hazard to public safety.

The first laboratory submission of acetyl fentanyl was recorded in Maine in April 

2013 according to the National Forensic Laboratory Information System1(NFLIS). 

Acetyl fentanyl was first reported to DEA’s System to Retrieve Information from Drug 

Evidence2(STRIDE), in September of 2013 from exhibits obtained through a controlled 

purchase in Louisiana. In October 2013, an exhibit collected from a controlled purchase

of suspected oxycodone tablets in Rhode Island contained acetyl fentanyl as the primary 

substance. STARLiMS (a web-based, commercial laboratory information management 

system that is in transition to replace STRIDE) and STRIDE reported eight additional 

seizures in 2014, in Colorado, Florida, Georgia, and Washington. NFLIS registered eight 

reports containing acetyl fentanyl in 2013, in Louisiana, Maine, and North Dakota, and 

30 in 2014, in Florida, Illinois, Louisiana, Maine, New Jersey, Ohio, Oregon, 

Pennsylvania, and Virginia.

In August 2013, the Centers for Disease Control and Prevention (CDC) published 

an article in its Morbidity and Mortality Weekly Report documenting a series of 14 

fatalities related to acetyl fentanyl that occurred between March and May 2013 (CDC, 

2013). Ten overdose fatalities in the months of March and April 2013 tested positive for 

fentanyl in blood by ELISA, however fentanyl was not detected by confirmatory gas

chromatography/mass spectrometry (GC/MS) analysis. These data were consistent with 

acetyl fentanyl. During the field investigation by the CDC and Rhode Island public 

health officials, two more fatalities were associated with acetyl fentanyl. Of these 12 

fatalities, intravenous administration was suspected in at least four of these deaths. 

Acetyl fentanyl was the only substance detected in one decedent and was found in 

combination with other substances such as cocaine, other opioids, ethanol and/or 

benzodiazepines in ten of the decedents. Importantly, fentanyl was not detected by 

GC/MS in any of these fatalities. Two additional fatalities involving acetyl fentanyl 

occurred in May 2013 (CDC, 2013), and one additional fatality in December 2013 

 

1 NFLIS is a program of the DEA that collects drug identification results from drug cases analyzed by other 

Federal, State, and local forensic laboratories. NFLIS, other federal, state, and local forensic drug reports 

were queried on 02/03/2015 (data are still being reported for November 2014 and December 2014).

2

STRIDE collected the results of drug evidence analyzed at DEA laboratories and reflects evidence 

submitted by the DEA, other Federal law enforcement agencies, and some local law enforcement agencies. 

STRIDE data was queried through 09/30/2014 by date submitted to Federal forensic laboratories. Since 

October 1, 2014, STARLiMS replaced STRIDE as the DEA laboratory drug evidence data system of 

record. DEA laboratory data submitted after September 30, 2014 are reposited in STARLiMS.
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(Rhode Island Department of Health, personal communication) increasing the number of 

deaths associated with acetyl fentanyl in Rhode Island to 15 through 2013. 

In February 2014, the North Carolina Department of Health and Human Services 

issued a health advisory related to acetyl fentanyl following at least three deaths related to 

this synthetic drug. Toxicologists at the Office of the Chief Medical Examiner detected 

acetyl fentanyl in biological samples associated with deaths that occurred in January in 

Sampson, Person and Transylvania counties. In July and August 2014, four additional 

fatalities involving acetyl fentanyl were reported. Deaths involving acetyl fentanyl have 

also been reported in California (1), Louisiana (14), Oregon (1) and Pennsylvania (1). 

A significant seizure of acetyl fentanyl occurred in April 2013 during a law 

enforcement investigation in Montreal, Canada. Approximately three kilograms of acetyl 

fentanyl in powder form and approximately 11,000 tablets containing acetyl fentanyl 

were seized. Given that a typical dose of acetyl fentanyl is in the microgram range, a 

three kilogram quantity could potentially produce millions of dosage units. 

In the United States, tablets that mimic pharmaceutical opiate products have been 

reported in multiple states, including Rhode Island, Colorado, Georgia, Florida and 

Washington. Recent reports indicate that acetyl fentanyl in powder form is available over 

the Internet and has been shipped to addresses within the United States. 

The pattern of abuse of fentanyl analogues, including acetyl fentanyl, parallels 

that of heroin and prescription opioid abusers. Seizures of acetyl fentanyl have been

encountered both in powder and in tablet form. It is also supported by the profile of 

many fatal overdose reports that document intravenous route of administration and 

histories of drug abuse (CDC, 2013; medical examiner report communicated by Chief 

Medical Examiner, Chapel Hill, North Carolina).

Factor 5. Scope, Duration, and Significance of Abuse

Fatalities associated with acetyl fentanyl have been reported in six states in 2013

and 2014, including California, Louisiana, North Carolina, Oregon, Pennsylvania, and

Rhode Island. STARLiMS and STRIDE, databases capturing drug evidence information

from DEA forensic laboratories, have a total of 10 drug reports in which acetyl fentanyl

was identified in six cases for analyzed drugs submitted from January 2010 – December 

2014 from Colorado, Florida, Georgia, Louisiana, Rhode Island and Washington. (query 

date: February 3, 2015).
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Populations likely to abuse acetyl fentanyl are likely to coincide with populations 

abusing prescription opioid analgesics and heroin, however the presence of acetyl 

fentanyl may be unknown to the end user. According to the National Survey on Drug 

Use and Health (NSDUH3), in 2013, the number of persons aged 12 or older who are 

current (used within the past month) nonmedical users of pain relievers (opioids) were 

4.5 million and the number of current users of heroin was 289,000. The NSDUH data 

also indicate that in 2013 an estimated 1.9 million persons aged 12 or older were 

classified with past year substance use disorder (dependence and abuse) of pain relievers 

and the corresponding number for heroin was 517,000. This population is likely to be at 

risk of abusing acetyl fentanyl. Because acetyl fentanyl is an opioid, individuals who 

initiate (i.e. use an illicit drug for the first time) acetyl fentanyl abuse are likely to be at 

risk of developing substance use disorder, overdose and death similar to that of other 

opioid analgesics (e.g., fentanyl, morphine, etc.). 

Further, because abusers of acetyl fentanyl are likely to obtain the drug through 

unknown sources, the identity, purity, and quantity are uncertain, thus posing significant 

adverse health risks to its users. This risk is particularly heightened by the fact that acetyl 

fentanyl is a highly potent opioid (15.7-fold more than that of morphine as tested in mice

using an acetic acid writhing method) (Higashikawa and Suzuki, 2008). Thus, small 

changes in the amount and purity of the substance could potentially lead to overdose and 

death. 

Factor 6. What, if Any, Risk There Is to the Public Health

Acetyl fentanyl exhibits a pharmacological profile similar to that of fentanyl and 

other μ-opioid receptor agonists (Jacobson, 1987; Higashikawa and Suzuki, 2008). In a 

study using tail flick (ED50 = 0.3 mg/kg/s.c.; morphine, ED50 = 5.8 mg/kg/s.c.) and 

phenylquinone writhing tests (ED50 = 0.05 mg/kg/s.c.; morphine, ED50 = 0.23 mg/kg/s.c.) 

acetyl fentanyl produced opioid-like analgesic response in mice (Jacobson, 1987). Acetylfentanyl has been shown to completely suppress the signs of withdrawal in morphinedependent monkeys with a single dose. In this study, acetyl fentanyl rapidly but briefly (90 

minute), substituted completely for morphine at 0.5 mg/kg. At peak effect, acetyl fentanyl is 

considered to be six times as potent as the reference standard morphine (Jacobson, 1987). 

In another study using a different mouse writhing model, acetyl fentanyl also demonstrated 

 

3 The National Survey on Drug Use and Health, formerly known as the National Household Survey on 

Drug Abuse (NHSDA), is conducted annually by the Department of Health and Human Services Substance 

Abuse and Mental Health Services Administration (SAMHSA). It is the primary source of estimates of the 

prevalence and incidence of nonmedical use of pharmaceutical drugs, illicit drugs, alcohol, and tobacco use 

in the United States. The survey is based on a nationally representative sample of the civilian, noninstitutionalized population 12 years of age and older. The survey excludes homeless people who do not 

use shelters, active military personnel, and residents of institutional group quarters such as jails and 

hospitals. The NSDUH provides yearly national and state level estimates of drug abuse, and includes 

prevalence estimates by lifetime (i.e., ever used), past year and past month abuse or dependence. 
DEA/OD/ODE page 6 of 10 April 27, 2015

a potent μ-opioid receptor agonist effect with an effective dose (ED50) of 0.021 mg/kg, 

making it 1/3 as potent as fentanyl (ED50=0.0061 mg/kg) and 15.7 times as potent as 

morphine (ED50=0.33 mg/kg). In addition, in vivo pharmacology studies performed in mice 

suggest that the range between ED50 and lethal dose (LD50) of acetyl fentanyl is narrower 

than that of morphine and fentanyl (acetyl fentanyl: ED50= 0.021 mg/kg, LD50=9.3 mg/kg; 

morphine: ED50=0.33 mg/kg, LD50=470 mg/kg; fentanyl: ED50=0.0061 LD50, LD50=62

mg/kg), increasing the risk of fatal overdose (Higashikawa and Suzuki, 2008). In view of 

this narrow dose range of acetyl fentanyl and its high potency, its abuse is likely to pose

quantitatively greater risks to the public health and safety than traditional opioid analgesics

such as morphine.

Based on the above pharmacological data, the abuse of acetyl fentanyl leads to the 

same qualitative public health risks as heroin, fentanyl and other opioid analgesics. The 

public health risks attendant to the abuse of heroin and other opioid analgesics are wellestablished (i.e. Brunton et al., 2010; Martin, 1977; Maxwell, 2011). The abuse of opioid

analgesics has resulted in large numbers of treatment admissions (Ling et al., 2011; 

SAMHSA, 2012), emergency department visits (Cai et al., 2010; SAMHSA, 2013), and 

fatal overdoses (Paulozzi, 2012; CDC, 2014). 

According to the Treatment Episode Data Set (TEDS)4of the Substance Abuse and 

Mental Health Services Administration (SAMHSA)5, in 2012, the number of persons aged 

12 or older admitted for the treatment for heroin as the primary substance of abuse was

285,451 and the corresponding number for other opioid analgesics (“Other 

opiates/synthetics”) was 169,868. The 2012 numbers for other opioid analgesics were over 

five-fold higher than the corresponding numbers in 2000 (28,326 admissions) (SAMHSA, 

2012, 2014).

According to the Drug Abuse Warning Network (DAWN)6of the SAMHSA, in 

2011, the number of emergency department (ED) visits involving abuse of heroin was

 

4 TEDS is a program coordinated and managed by the Substance Abuse and Mental Health Services 

Administration (SAMHSA). This database includes information on treatment admissions that are routinely 

collected by states to monitor their individual substance abuse treatment systems. Thus, TEDS includes 

data primarily from treatment facilities that receive public funds. TEDS includes information on 

demographic variables including age, gender, race and ethnicity. TEDS also reports on the top three drugs 

of abuse at the time of admission. TEDS does not include all drugs that may have been abused prior to 

admission. States and jurisdictions can choose whether or not to report the detailed listing.

5 The Substance Abuse and Mental Health Services Administration (SAMHSA) is a branch of the U.S. 

Department of Health and Human Services (HHS). It is charged with improving the quality and 

availability of prevention, treatment, and rehabilitative services in order to reduce illness, death disability, 

and cost to society resulting from substance abuse and mental illness.

6 The Drug Abuse Warning Network (DAWN) is a public health surveillance system that monitors drug 

related hospital emergency department (ED) visits to track the impact of drug use, misuse, and abuse in the 
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258,482 and the corresponding number for opioid analgesics (“Narcotic Pain Relievers”) 

was 420,040. In 2011, ED visits involving opioid analgesics were 153 percent more than in 

2004 (SAMHSA, 2013). 

Prescription opioid analgesic-related deaths have increased in the past 15 years. 

From 1999 to 2013, the number of U.S. drug poisoning deaths involving any opioid 

analgesic (e.g., oxycodone, methadone, or hydrocodone) more than quadrupled, from 1.4 to 

5.1 per 100,000 population, accounting for 37% (16,235 opioid deaths) of the 43,982 drug 

poisoning deaths in 2013 (CDC, 2015). Prescription opioid analgesic-related deaths were 

recently discussed by DEA (DEA, 2014). In the decade from 2002 to 2011, the annual 

number of drug poisoning deaths involving heroin doubled, from 2,089 deaths in 2002 to 

4,397 deaths in 2011 (CDC, 2014).

Similar to heroin and other opioid analgesics, acetyl fentanyl has been associated 

with numerous fatalities. Thirty nine confirmed deaths associated with acetyl fentanyl 

abuse have been reported in six states in 2013 and 2014, including California, Louisiana, 

North Carolina, Oregon, Pennsylvania, and Rhode Island. This indicates that acetyl fentanyl 

poses an imminent hazard to public safety. 

Conclusion of 3-Factor Analysis

After a careful review of the scientific literature, Factors 4, 5, and 6, NFLIS, 

STRIDE, and other law enforcement data and other sources of information, it is evident that 

acetyl fentanyl is trafficked and abused, and that it poses an imminent hazard to public 

safety.

DEA has considered the three criteria for placing a substance into Schedule I of the 

CSA (21 U.S.C. 812). The data available and reviewed for acetyl fentanyl indicates that 

acetyl fentanyl, including its isomers, esters, ethers, salts, and salts of isomers, esters and 

ethers poses an imminent hazard to public safety and health, has no currently accepted 

medical use in treatment in the United States, and lacks accepted safety for use under 

medical supervision.

 

United States. It is sponsored by the SAMHSA and collects data on drug-related emergency department 

(ED) visits from a nationally representative sample of hospitals in the U.S. and a selection of metropolitan 

areas. A DAWN case is any ED visit involving recent drug use that is implicated in the ED visit. DAWN 

captures both ED visits that are directly caused by drugs and those in which drugs are a contributing factor 

but not the direct cause of the ED visit. Annually, DAWN produces estimates of drug-related visits to 

hospital EDs for the nation as a whole and for selected metropolitan areas. 
DEA/OD/ODE page 8 of 10 April 27, 2015

References

Brunton LB, Lazo JS, Parker KL, eds. (2010). Goodman & Gilman's The

Pharmacological Basis of Therapeutics. 12th ed. New York: McGraw-Hill. 

Cai R, Crane E, Poneleit K, Paulozzi L (2010). Emergency department visits involving 

nonmedical use of selected prescription drugs in the United States, 2004-2008. Journal of 

Pain & Palliative Care Pharmacotherapy 24: 293-297.

Centers for Disease Control and Prevention (CDC) (2013). Acetyl fentanyl overdose 

fatalities--Rhode Island, March-May 2013. MMWR Morbidity and Mortality Weekly 

Report 62(34); 703-4.

Centers for Disease Control and Prevention (CDC) (2014). QuickStats: Rates of Drug 

Poisoning Deaths Involving Heroin, by Selected Age and Racial/Ethnic Groups —

United States, 2002 and 2011. MMWR Morbidity and Mortality Weekly Report 63(27);

595.

Centers for Disease Control and Prevention (CDC) (2015). QuickStats: Rates of Deaths 

from Drug Poisoning and Drug Poisoning Involving Opioid Analgesics – United States, 

1999-2013. MMWR Morbidity and Mortality Weekly Report 64 (1); 32.

Drug Enforcement Administration (DEA) (2014). Schedules of Controlled Substances:

Placement of Hydrocodone Combination Products into Schedule II Background, Data, 

and Analysis: Eight Factors Determinative of Control and Findings Pursuant to 21 U.S.C. 

812(b). Available on regulations.gov; document ID DEA-2014-0005-0003.

Higashikawa Y, Suzuki S (2008). Studies on 1-(2-phenethyl)-4-(N-propionylanilino) 

peperidine (fentanyl) and its related compounds. VI. Structure-analgesic activity 

relationship for fentanyl, methyl-substituted fentanyls and other analogues. Forensic 

Toxicology 26:1–5. 

Jacobson A (1987). Biological evaluation of compounds for their physical dependence 

potential and abuse liability Xl. Drug testing program of the committee on problems of 

drug dependence, NIDA Research Monograph 81, 466-84.

Janssen PAJ, van der Eycken CAM (1968). The chemical anatomy of potent morphinelike analgesics in Drugs Affecting the Central Nervous System, Vol. 2, A. Burger, Ed., 

Marcel Dekker, New York, pp. 25-60.

Ling W, Mooney L, Hillhouse M (2011). Prescription opioid abuse, pain and addiction: 

Clinical issues and implications. Drug and Alcohol Review 30: 300-5.
DEA/OD/ODE page 9 of 10 April 27, 2015

Martin WR (ed) (1977). Drug addiction: I. Morphine, sedative-hypnotic, and alcohol 

dependence. Springer, Berlin Heidelberg New York (Handbook of experimental 

pharmacology, vol 45

Maxwell JC (2011). The prescription drug epidemic in the United States: A perfect 

storm. Drug and Alcohol Review 30: 264-70.

North Carolina Department of Health and Human Services (2014). DHHS Issues Health 

Advisory for Deadly New Synthetic Drug. Acetyl Fentanyl Detected in Specimens 

Associated With Three N.C. Deaths This Year. Available at 

http://www.ncdhhs.gov/pressrel/2014/2014-02-19_health_advisory.htm

Paulozzi LJ (2012). Prescription drug overdoses: A review. Journal of Safety Research.

43: 283-9.

Pennsylvania Department of Drug and Alcohol Programs (2013). Department of Drug 

and Alcohol Programs warns about acetyl fentanyl: drug caused at least 50 fatalities this 

year in Pennsylvania. Harrisburg, PA: Pennsylvania Department of Drug and Alcohol 

Programs; Available at http://www. 

pa.gov/portal/server.pt/document/1345188/department_of_drug_and_alcohol_programs_

warns_about_acetyl_fentanyl. 

Roberts JR (2013). InFocus: Acetyl Fentanyl: New Drug of Abuse More Common than 

Assumed." Emergency Medicine News 35.12: 1-28.

Stogner JM (2014). The potential threat of acetyl fentanyl: legal issues, contaminated 

heroin, and acetyl fentanyl "disguised" as other opioids. Annals of Emergency Medicine

64:637-9

Substance Abuse and Mental Health Services Administration, Center for Behavioral 

Health Statistics and Quality (2012). Treatment Episode Data Set (TEDS): 2000-2010. 

National Admissions to Substance Abuse Treatment Services. DASIS Series S-61, HHS 

Publication No. (SMA) 12-4701. Rockville, MD, Substance Abuse and Mental Health 

Services Administration.

Substance Abuse and Mental Health Services Administration, Center for Behavioral 

Health Statistics and Quality (2013). The DAWN Report: Highlights of the 2011 Drug 

Abuse Warning Network (DAWN) Findings on Drug-Related Emergency Department 

Visits. Rockville, MD, Substance Abuse and Mental Health Services Administration.

Substance Abuse and Mental Health Services Administration, Center for Behavioral 

Health Statistics and Quality (2014). Treatment Episode Data Set (TEDS): 2002-2012. 

National Admissions to Substance Abuse Treatment Services. DASIS Series S-71, HHS 

Publication No. (SMA) 14-4850. Rockville, MD, Substance Abuse and Mental Health 

Services Administration.
DEA/OD/ODE page 10 of 10 April 27, 2015

Appendix A. Control and Emergency Control of Substances Structurally related to 

Fentanyl.

Appendix A

FEDERAL FEDERAL PROPOSAL FEDERAL PROPOSAL FEDERAL

PUB REGISTER CSA PUB REGISTER CSA PUB PUB REGISTER CSA PUB PUB REGISTER CSA

SUBSTANCE DATE CITATION SCHEDULE DATE CITATION SCHEDULE DATE DATE CITATION SCHEDULE DATE DATE CITATION SCHEDULE

Sufentanyl 09-30-80 45 FR 64571 03-20-84 05-25-84 49 FR 22074 I -> II

Alpha-Methylfentanyl 08-05-81 09-22-81 46 FR 46799 I Narcotic

Alfentanyl 06-25-84 49 FR 25849 I Narcotic 04-17-86 01-23-87 52 FR 2516 I -> II 

Narcotic

3-Methylfentanyl 03-25-85 50 FR 11690 I 04-24-86 51 FR 15474 I 04-24-86 09-22-86 51 FR 33592 I Narcotic

Beta-Hydroxyfentanyl 10-29-85 50 FR 43698 I 11-26-86 51 FR 42834 I 11-28-86 05-29-87 52 FR 20070 I Narcotic

Benzylfentanyl 10-29-85 50 FR 43698 I Expired 

11/29/1986

Beta-Hydroxy-3-Methylfentanyl 10-29-85 50 FR 43698 I 11-26-86 51 FR 42834 I Expired 

5/29/1987 11-28-86 01-08-88 53 FR 500 I Narcotic

Acetyl-Alpha-Methylfentanyl 10-29-85 50 FR 43698 I 11-26-86 51 FR 42834 I 11-28-86 05-29-87 52 FR 20070 I Narcotic

Thiofentanyl 10-29-85 50 FR 43698 I 11-26-86 51 FR 42834 I 11-28-86 05-29-87 52 FR 20070 I Narcotic

Thenylfentanyl 10-29-85 50 FR 43698 I Expired 

11/29/1986

3-Methylthiofentanyl 10-29-85 50 FR 43698 I 11-26-86 51 FR 42834 I 11-28-86 05-29-87 52 FR 20070 I Narcotic

Alpha-Methylthiofentanyl 10-29-85 50 FR 43698 I 11-26-86 51 FR 42834 I 11-28-86 05-29-87 52 FR 20070 I Narcotic

Para-Fluorofentanyl 02-07-86 51 FR 4722 I 03-10-87 52 FR 7270 I 03-10-87 05-29-87 52 FR 20070 I Narcotic

Carfentanil 01-12-88 10-28-88 53 FR 43684 II Narcotic

Remifentanil 09-16-96 11-05-96 61 FR 56893 II Narcotic

TEMPORARY SCHEDULING under 21 

USC 811(h)

EXTENSION OF TEMPORARY 

SCHEDULING

PERMANENT SCHEDULING RESCHEDULING from CI to CII