Fentanyl abuse

As mentioned above, most reports of fentanyl abuse have not involved iatrogenic addiction in patients. As with butorphanol, the human experimental data most consistent with this did not appear until 1996, when it was shown that the euphoriant effects of fentanyl are blunted in the presence of a painful stimulus.106 Clearly, however, low incidence of iatrogenic addiction or abuse may not predict the likelihood of abuse in nonpatient populations. 

Fentanyl abuse among non-medical personnel has come in waves as new derivatives are discovered. However, the problem is growing in the United States. The Substance Abuse and Mental Health Services Administration (SAMHSA) states that 576 people were treated in emergency rooms for fentanyl abuse in 2000. This is higher than the 337 recorded instances in 1999. Figures from 2001 are incomplete, but at least 512 people were treated in emergency rooms in the first six months of the year. Since fentanyl is difficult to detect, these figures are believed to be lower than actual cases. 

Arvanitis ML and Satonik RC (2002) Transdermal fentanyl abuse and misuse (letter). American Journal of Emergency Medicine 20 58-59. 

M. S. Gold, R. J. Melker, D. M. Dennis, T. E. Morey, L. K. Baipai, R. Pomm and K. Frost-Pineda, Fentanyl abuse and dependence further evidence for second hand exposure hypothesis, J. Addict. Dis., 2006, 25, 15-21. 

Schedule II—The drug or other substance has (1) a high potential for abuse, (2) a currently accepted medical use in treatment in the United States or a currently accepted medical use with severe restrictions, and (3) abuse of the drug or other substances may lead to severe psychological or physical dependence. Examples cocaine, PCP, morphine, fentanyl and meperidine, codeine, amphetamine and methamphetamine, Ritalin . 

Fentanyl transdermal system Fentanyl transdermal systems contain a high concentration of the potent schedule II opioid agonist, fentanyl. Schedule II opioid substances have the highest potential for abuse and associated risk of fatal overdose due to respiratory depression. Fentanyl can be abused and is subject to criminal diversion. The high content of fentanyl in the patches may be a particular target for abuse and diversion. 

Schedule 2 is intended for drugs that also have a high potential for abuse and for addiction but do have a currently accepted medical use, albeit often a highly restricted one. These drugs include many opiates that are used medically, as well as certain coca extracts. Examples include fentanyl and methadone (the latter being used medically for maintenance of heroin addicts). 

Fentanyl and fentanyl derivatives (so-called designer drugs) have a fundamental abuse potential (Buchanan and Brown, 1988)) and induce morphine-type physical dependence. 

Numerous studies have reported that performance on the DSST was impaired by various opioids, including morphine (2.5 to 10 mg),185,198 fentanyl (1 to 2.5 ng/ml),182 pentazocine (30 mg),184 butorphanol (0.5 to 2 mg),186 dezocine (2.5 to 10 mg),187 propofol (22 to 70 mg),193,199 nalbuphine (2.5 to 10 mg, IV),189 and the combination of fentanyl (50 pg) plus propofol (35 mg).194 In contrast, meperidine was found to have no effect on the DSST.192 Because the DSST is a timed test, it would appear that opioids slow speeded responses in a fairly consistent manner in opioid-naive subjects. However, in opioid abusers or opioid-dependent persons, Preston and colleagues have reported no effect on DSST performance of several opioids, including morphine (7.5 to 30 mg, IM),200 hydro-morphone (0.125 to 3 mg, IM),201 buprenorphine (0.5 to 8 mg, IM),202 pentazocine (7.5 to 120 mg, IM),203 butorphanol (0.375 to 1.5 mg, IV),204 and nalbuphine (3 to 24 mg, IM).205... 

Because faster onset of action is associated with higher potential for abuse, abuse-liability assessment should include consideration of whether a formulation can be altered to increase the speed of onset. There are numerous examples of abuse of a medication by a route other than that intended by the manufacturer. The sustained-release oral form of oxycodone, designed to deliver an initial rapid dose followed by slow release, has been widely abused by chewing the tablet, thus releasing the entire content of the tablet at once.65 There is also evidence for intravenous use of sublingual buprenorphine tablets.66 Transdermal systems developed to deliver medication slowly for extended periods of time have been prime targets for misuse,67 as discussed below in the case study of fentanyl. 

For each drug, the prevalence of abuse was partly attributable to its absolute availability — for example, the over-the-counter status of dextromethorphan (DXM) or the expansion of fentanyl and butorphanol from inpatient to outpatient use. But the pattern of abuse for each drug was distinctive and probably could not have been predicted from the available experimental abuse-liability data. 

Table 8.2 shows a selective timeline of the evaluation, abuse, and regulation of fentanyl, a potent agonist at mu-opioid receptors. Again, the most salient aspects of the drug s recent history can be summed up with two questions. 

Why was this pattern not predicted The highly euphorogenic nature of fentanyl was actually clear in abuse-liability studies as early as 1965,104 and the drug was accordingly placed in Schedule II of the 1970 Controlled Substances Act this was the most restrictive possible placement that still permitted medical use. What was apparently not foreseen, when the patch formulation was approved for outpatient use in 1990, was that its slow-release properties would be defeated by individuals seeking intoxication. The published literature appears to contain no abuse-liability studies for the patch formulation. 

Earlier in the chapter, we pointed out that the relationship between drug availability and abuse may wax and wane over time. In the case of fentanyl, this can be seen in the differing results of... 

Flannagan, L.M., Butts, J.D., and Anderson, W.H., Fentanyl patches left on dead bodies — potential source of drug for abusers, J. Forensic Set, 41, 320, 1996. 

DeSio, J.M. et al., Intravenous abuse of transdermal fentanyl therapy in a chronic pain patient, Anesthesiology, 79, 1139, 1993. 

Anonymous, Rangel bill would equate fentanyl with heroin, Alcoholism Drug Abuse Week, 4, 6, 1992. 

Schedule II. Drugs in this category are approved for specific therapeutic purposes but still have a high potential for abuse and possible addiction. Examples include opioids such as morphine and fentanyl, and drugs containing methampheta-mine. 

Fentanyl was first abused by medical professionals who were able to obtain the legally produced opioid from drug companies. Today, it is a designer drug that black market chemists in clandestine laboratories with high levels of expertise and equipment manufacture in home labs. As a street drug, it can be several hundred to three thousand times more potent than morphine. Sometimes it is sold as heroin to unsuspecting users. 

It is known that the abuse of prescription fentanyl is on the rise, but the degree of increase is difficult to distinguish. Doctors are increasingly wary of turning down requests for pain medication for fear of lawsuits if the patient truly is in a lot of pain. Determining how much pain a patient feels is nearly impossible for the doctor, so they must rely on what the patient tells them. This has led to an increase of people illicitly getting pain relievers for personal use or distribution. Some patients lie to their doctors about their conditions in order to get painkillers others have gone to several doctors to get several prescriptions. 

Other than anesthesiologists, many professionals within the medical community abuse fentanyl. However, the majority of these are considered to be less skilled healthcare workers, rather than the pharmacists or doctors who abuse other drugs. Namely, abusers who steal fentanyl from hospitals are usually nursing aides and uncertified healthcare providers. 

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