Introduction
Oxycodone abuse has been a continuing
problem in the United States since the early 1960's. In passing the
Controlled Substances Act of 1970, Congress placed oxycodone in
Schedule II (CII). In spite of its CII status, oxycodone continued to
be abused. The abuse of a new sustained-release formulation of
oxycodone, known as Oxycontin7, has escalated over the last year. Drug
abuse treatment centers, law enforcement personnel, and health care
professionals have reported a dramatic increase in the abuse of these
sustained release products in Maine, Virginia, West Virginia, Ohio,
Kentucky and Maryland. Recently, abuse has spread to other states such
as Pennsylvania and Florida. The estimated number of emergency
department (ED) episodes involving oxycodone were stable from 1990
through 1996. However, the number of ED episodes more than trippled
from 1996 to 2000: 3,190 episodes in 1996 to 10,825 in 2000.
Licit Uses
Oxycodone is an effective analgesic for mild
to moderate pain control, chronic pain syndromes, and for the
treatment of terminal cancer pain. Five mg of oxycodone is equivalent
to 30 mg of codeine when administered orally. Oxycodone and morphine
are equipotent for pain control in the normal population; 10 mg of
orally-administered oxycodone is equivalent to 10 mg of subcutaneously
administered morphine. Oxycodone is considered to be similar to
morphine, in all respects, including its abuse & dependence liabilties.
Oxycodone in dosages of 5 to 10 mg in combination with acetaminophen
or aspirin are abused orally. High dose single entity sustained
release formulations containing 10 to 80 mg of oxycodone are abused by
crushing or chewing the tablet and then swallowing, snorting or
injecting the drug.
Chemistry/Pharmacology
Oxycodone
[4,5a-epoxy-14-hydroxy-3-methoxy-17-methylmorphinan-6-one,
dihydrohydroxycodeinone] is a semisynthetic opioid structurally
related to codeine and is approximately equipotent to morphine in
producing opiate-like effects. The first report that oxycodone, sold
under the brand name Eukodal, produced a "striking euphoria" and
habituation symptoms was published in Germany in the 1920's. While
oxycodone is metabolized by the liver to oxymorphone, the
physiological and behavioral effects are not related to, nor dependent
on, the formation of this metabolic by-product.
Oxycodone will test positive for an opiate
in the available field test kits.
Illicit Uses
Oxycodone is abused for its opiate-like
effects. In addition to its equipotency to morphine in analgesic
effects, it is also equipotent to morphine in relieving abstinence
symptoms from chronic opiate (heroin, morphine) administration.For
this reason, it is often used to alleviate or prevent the onset of
opiate withdrawal by street users of heroin and methadone. In early
studies by the Addiction Research Center in Lexington, Kentucky in the
1960's, it was discovered that the subjective and physiological
effects of oxycodone were greater than an equivalent
dose of morphine in opiate substance abusers. Many dosage forms are
available. Oxycodone’s behavioral effects can last up to 5 hours. The
drug is most often administered orally. The sustained-release formula
has a longer duration of action (8-12 hours). A recent study comparing
controlled released products containing oxycodone (Oxycontin) and
morphine (MS Contin) reported that Oxycontin was twice as potent as MS
Contin.
As with most opiates, the adverse effects
of oxycodone abuse are dependence and tolerance development.
Oxycodone’s co-formulation with acetaminophen has also increased the
likelihood of acetaminophen-induced hepatic necrosis with chronic
dosing. Its availability in sustained release formulations has
increased the dosage forms from 10 to 160 mg per tablet making it more
attractive than oxycodone to opiate abusers and doctor-shoppers. The
original idea of polymer-formulations of oxycodone was to reduce the
likelihood of misuse with high dose formulations. Opiate abusers
quickly learned the ease of extraction of the molecule from the
polymer formula and have been injecting or snorting the crushed and/or
dissolved tablets because of its’ higher dosage formulations.
User Population
Every age-group has been affected by the
relative ease of oxycodone availability and the perceived safety of
these products by professionals. Sometimes seen as a "white-collar"
addiction, oxycodone abuse has increased among all ethnic and economic
groups.
Illicit Distribution
Oxycodone-containing products are in tablet,
capsule and liquid forms. A variety of colors, markings, and packaging
are available.
The major source of oxycodone to the
street has been through forged prescriptions, professional diversion
through unscrupulous pharmacists, doctors, and dentists,
"doctor-shopping", and large-scale thefts. Oxycontin7
sells for $0.50 to $1.00 per milligram. A 40 mg tablet is sold for
$25-$40, and the 80 mg tablets are being sold for $65-$80. The
manufacturer has recently discontinued marketing the 160 mg tablets.