Propoxyphene 391bat their withdrawal symptoms. Propoxyphene is related tomethadoneso
closely that propoxyphene can cause a false positive for methadone in drug
screens.
Drawbacks.Normal medical doses of propoxyphene seldom produce un-
wanted effects, but those can include nausea, vomiting, constipation, sleepi-
ness, and dizziness. Occasional cases of liver damage have been attributed to
the drug. Extended use of propoxyphene suppositories can cause ulcerations.
Injecting the drug can cause muscle damage at the injection site, and injecting
the oral format can cause lung damage. Blood sugar levels can drop when
taking propoxyphene, a condition that is easy to treat but that can become
serious if ignored (as when an abuser is unconscious). A study of medical
records found seizures to be common among abusers who had taken high
doses daily for years, but those records did not demonstrate cause and effect.
Case reports have attributed deafness and blindness to propoxyphene abuse.
Examination of thousands of medical records determined that old people who
use propoxyphene are more likely to become unsteady and break their hips
in a fall, and this risk increases if the old persons are also taking drugs in-
tended to alter their mental state. Propoxyphene may cause euphoria. That
effect is noted in horses as well; the substance also makes them more physi-
cally active, perhaps tempting unscrupulous individuals to dose horses before
races.
One human experiment found that the substance slowed reaction times and
interfered with recognizing pictures, results that may be relevant to driving
skills. Another study using the same dosage, however, found the drug to have
no significant impact on decision making, picture recognition, or reaction time.
Investigators running still another experiment concluded that the normal
doses of the drug do not impair driving. Nonetheless, people are supposed
to be warned against operating dangerous machinery while using the drug.
Propoxyphene overdose deaths became so common in the 1970s that the
U.S. Food and Drug Administration warned that the dangers of this mild drug
needed more respect from prescribers and users. Similar concerns were ex-
pressed in Great Britain during the 1980s, in Denmark during the 1990s, and
in Sweden as the twenty-first century began.
Abuse factors.Despite propoxyphene’s relative mildness, tolerance and de-
pendence can occur if a person takes large doses long enough. Case reports
tell of individuals who became so addicted that switching the persons to meth-
adone became necessary. Other case reports relate instances of propoxyphene
dependence so strong that psychosis developed during withdrawal. Propox-
yphene itself has been used as a maintenance drug for addicts being switched
from some other opiate/opioid. One study found propoxyphene to be about
80 times weaker than methadone when used for this purpose.
A study noted that a group of adolescents being treated for illicit propox-
yphene use had multiproblem lifestyles, and analysis of propoxyphene over-
dose deaths in Los Angeles revealed that all the persons had led troubled lives
involving different drug overdoses, arrests, strife with other persons, mental
afflictions, and suicide attempts. That analysis prompted the investigator to
ask whether availability of this drug and other opiates/opioids posed a risk
to normal persons or just to abnormal people. Other research presented find-