Oxycodone
(Trade Names: Tylox, Percodan, Oxycontin)
Introduction
Oxycodone is synthesized from thebaine. Like morphine
and hydromorphone, Oxycodone is used as an analgesic. It is effective orally
and is marketed alone in 10, 20, 40, 80, and 160 mg controlled-release tablets
(OxyContin), or 5 mg immediate-release capsules (OxyIR®), or in combination
products with aspirin (Percodan®) or acetaminophen (Percocet®) for the
relief of pain. All oxycodone products are in Schedule II. Oxycodone is abused
orally or the tablets are crushed and sniffed or dissolved in water and
injected. The use of oxycodone has increased significantly. In 1990, nearly
three tons of Oxycodone were manufactured in the United States. In 2000, about
47 tons were manufactured
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.
Oxycodones 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. Oxycodones 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.
Control Status
Oxycodone products are in Schedule II of the
Controlled Substances Act of 1970.
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