09 March 2009

Pentazocine (Fortral, Fortralgesic, Fortralin, Fortwin, Liticon,Pentgin, Sosegon, Sosenyl, Talacen, Talwin, Talwin Nx)

Pronunciation: pen-TAZ-oh-seen
Chemical Abstracts Service Registry Number: 359-83-1. (Hydrochloride form 64024-15-3)
Formal Names: Fortral, Fortralgesic, Fortralin, Fortwin, Liticon, Pentgin, Sosegon, Sosenyl, Talacen, Talwin, Talwin Nx
Informal Names: 4 4s, Teacher, Ts, Yellow Footballs. Combination with methylphenidate:
Crackers, 1s & 1s, Poor Man’s Heroin, Ritz & Ts, Ts & Rits, Ts & Rs, Sets. Combination with tripelennamine: Ts & Blues, Ts & Bs
Type: Depressant.
Federal Schedule Listing: Schedule IV (DEA no. 9709)
USA Availability: Prescription
Pregnancy Category: C

Uses.
Pentazocine became available in the 1960s. Some authorities classify the drug as an opioid; some do not. Rather than having cross-tolerance with opiates and opioids, pentazocine can provoke a withdrawal syndrome from them. Volunteers who receive pentazocine have been uncertain about what sort of drug it is; some say it is a hallucinogen; some think they are receiving
alcohol.

Pentazocine has about the same pain relief strength as codeine. An experiment using oral surgery patients found pentazocine’s pain relief to be the same as aspirin’s. After drug abusers began grinding down Talwin tablets and injecting the powder to get morphine and heroin sensations, the manufacturer introduced Talwin Nx tablets, which include a chemical designed to block those sensations if the substance is injected. Dispute exists about whether the Nx version of Talwin actually prevents effects sought by illicit users.

Research indicates that women surgical patients tend to get better pain relief from pentazocine than male patients. Research also indicates that the drug’s surgical pain control is more effective for older patients and less effective for neurotics and for individuals with outgoing personalities.

The drug has been routinely used to ease cancer pain and has had success in reducing joint pain
caused by various afflictions, including arthritis. After noting that pentazocine does not prolong bleeding times, researchers called it suitable to fight pain from hemophilia, a blood disease that promotes bleeding. The substance has also been given as a treatment for stubborn cases of hiccups.

Investigators have documented that people can briefly experience euphoria after taking the drug. Some users feel more amiable and serene after a dose. Drawbacks. Unwanted pentazocine actions include rapid heartbeat, blood pressure changes (up or down), fainting, sweating, confusion, sleepiness, blurred vision, nausea, vomiting, and constipation. Studies have found that
1% to 10% of persons receiving the drug (especially an injectable pharmaceutical version) have odd psychological reactions such as hallucinations, delusions, or a sense of unreality about the world. The substance can interfere with decision making and physical movement. Research has shown that driving skills decline when a person uses the drug, and users should avoid operating
motor vehicles or other dangerous machinery. Because pentazocine has occasionally been associated with seizures, it should be used cautiously by persons prone to that affliction. The substance should also be used cautiously by people suffering from pancreas malfunction or breathing difficulty. The drug may be particularly hazardous for asthma sufferers who are overly sensitive to aspirin. Pentazocine is associated with skin hardening, which can result in
extensive surgical removal of affected areas, to be replaced with skin grafts.

Case reports tell of the drug provoking not only skin lesions but internal lesions in the digestive tract. Prolonged use of the substance can also cause muscle destruction that cripples a person’s ability to move arms and legs. The compound can dangerously reduce white blood cell levels. Rat experiments indicate the drug may provoke attacks of porphyria, a body chemistry disease
that can make people violent and sensitive to light.

One group of researchers documented that pentazocine increased the heart’s workload by 22% in cardiac disease patients. Another group found that after a heart attack the drug increases blood pressure and the heart’s need for oxygen and concluded that pentazocine is dangerous for heart attack patients.

Not all authorities agree with that conclusion, however; some say that such adverse cardiac effects can be avoided through careful dosage, and other opinion says the drug is preferable to morphine for heart attack patients.

Abuse factors.
Some abusers inject powder from oral pentazocine tablets.
Oral pentazocine tablets contain ingredients not intended for introduction into the bloodstream, and injection can be fatal even though the digestive system can handle the same ingredients without difficulty.

Pentazocine and the antihistamine-anesthetic tripelennamine are a common illicit drug combination called Ts & Blues, sometimes used as a substitute for heroin (“T” standing for Talwin and “Blues” for the antihistamine tablets’ color). The combination can create more euphoria than pentazocine alone produces and reduce the discontent caused by some doses of pentazocine. Users report development of memory trouble. Lung damage is a classic consequence of the combination, promoted by injecting oral formats of the drugs. Users
have been hospitalized with chest pain, anxiety, spasms, sweating, nausea, and lightheadedness. Fainting and seizures are less common problems. Kidney damage has been noted. Other antihistamines can also be dangerous to use with pentazocine.

Pentazocine tolerance and dependence can occur. After daily doses were given to monkeys for six weeks, mild withdrawal symptoms appeared when the animals received nalorphine, a substance that provokes withdrawal signs if someone has been using opioids. That result supports classifying pentazocine as an opioid, but in humans nalorphine does not cause pentazocine withdrawal— 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 physical 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 as methadone or 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 environment 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 antidepressants) 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. Examination 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 revealed 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 exposure to Ts & Blues, although the conduct may simply have been a temporary 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.

Additional scientific information may be found in:

Brogden, R.N., T.M. Speight, and G.S. Avery. “Pentazocine: A Review of Its Pharmacological
Properties, Therapeutic Efficacy and Dependence Liability.” Drugs 5
(1973): 6–91.

Debooy, V.D., et al. “Intravenous Pentazocine and Methylphenidate Abuse during
Pregnancy. Maternal Lifestyle and Infant Outcome.” American Journal of Diseases
of Children 147 (1993): 1062–65.

“Pentazocine.” British Medical Journal 2 (1970):409–10.

Saarialho-Kere, U., M.J. Mattila, and T. Seppala. “Parenteral Pentazocine: Effects on
Psychomotor Skills and Respiration, and Interactions with Amitriptyline.” European
Journal of Clinical Pharmacology 35 (1988): 483–89.

Showalter, C.V. “T’s and Blues: Abuse of Pentazocine and Tripelennamine.” Journal of
the American Medical Association 244 (1980): 1224–25.

Zacny, J.P., et al. “Comparing the Subjective, Psychomotor and Physiological Effects of
Intravenous Pentazocine and Morphine in Normal Volunteers.” Journal of Pharmacology
and Experimental Therapeutics 286 (1998): 1197–207.

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