362 Pentazocine
if someone has been using opioids. That result supports classifying pentazo-
cine as an opioid, but in humans nalorphine does not cause pentazocine with-
drawal—a result consistent with pentazocine not being an opioid. Pentazocine
withdrawal is normally likened to a light version of the opiate withdrawal
syndrome, although case reports tell of some persons suffering intense phys-
ical discomfort for up to two weeks (cramping muscles, painful abdomen and
back, nausea, itching, sweating, and general discomposure). Debate exists
about whether pentazocine addiction should be treated by substituting other
drugs such asmethadoneor whether treatment should avoid substitution
altogether. Some authorities have wondered if pentazocine addiction occurs
in persons who are not polydrug abusers. Some authorities even question
whether pentazocine addiction exists, noting cases in which body fluid testing
contradicted drug users’ claims to be using the drug (while indicating they
were using other substances). German researchers found that addiction reports
are at least exaggerated; upon investigation, only 8 of 60 reports turned out
to be authentic.
Drug interactions.Persons who smoke or who live in a polluted air envi-
ronment may need higher doses of pentazocine than persons who breathe
clean air. Morphine and pentazocine boost each other’s pain-relieving action.
Alcohol and possibly monoamine oxidase inhibitors (found in some antide-
pressants) may react badly with pentazocine.
Cancer.Animal research has not shown pentazocine to cause cancer.
Pregnancy.Normal production of litters has occurred when pentazocine
was given to pregnant rats and rabbits, and no birth defects were apparent.
The drug is absorbed by the fetus if a pregnant woman takes a dose. Exami-
nation of one hospital’s records of all pregnant patients who used pentazocine
illicitly in a two-year period showed that their infants tended to be premature
and undersized, but no malformation was attributed to the drug. Newborns
were occasionally dependent. Despite those disadvantages the children
seemed to develop normally in their first year of life. When pentazocine was
given simply as a pain reliever in childbirth, examination of the infants re-
vealed no difference from children born to women who did not receive a
medical dose of the drug during childbirth.
A study found Ts & Blues mothers to have an increased rate of assorted
diseases that would not promote healthy fetal development: hepatitis, anemia,
gonorrhea, syphilis. Such afflictions indicate a risk-taking lifestyle in which
prenatal care is a small concern. A survey of maternity records at one hospital
showed that pregnant women who used Ts & Blues tended to produce smaller
infants, but no major birth defects were associated with the drug combination.
Another study found behavioral abnormalities in newborns that had fetal ex-
posure to Ts & Blues, although the conduct may simply have been a tempo-
rary sign of drug withdrawal. Investigators running a rat experiment,
however, noted long-term behavioral differences between a group of rats
having fetal exposure to the drug combination and another group that was
unexposed.
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