Talacen Warnings, Precautions, Pregnancy, Nursing, Abuse - Pentazocine and Acetaminophen

Talacen Warnings, Precautions, Pregnancy, Nursing, Abuse - Pentazocine and Acetaminophen

WARNINGS

Contains sodium metabisulfite, a sulfite that may cause allergic-type reactions including anaphylactic symptoms and life-threatening or less severe asthmatic episodes in certain susceptible people. The overall prevalence of sulfite sensitivity in the general population is unknown and probably low. Sulfite sensitivity is seen more frequently in asthmatic than in nonasthmatic people.

Head Injury and Increased Intracranial Pressure.  As in the case of other potent analgesics, the potential of pentazocine for elevating cerebrospinal fluid pressure may be attributed to CO ₂ retention due to the respiratory depressant effects of the drug. These effects may be markedly exaggerated in the presence of head injury, other intracranial lesions, or a preexisting increase in intracranial pressure. Furthermore, pentazocine can produce effects which may obscure the clinical course of patients with head injuries. In such patients, TALACEN must be used with extreme caution and only if its use is deemed essential.

Acute CNS Manifestations.   Patients receiving therapeutic doses of pentazocine have experienced hallucinations (usually visual), disorientation, and confusion which have cleared spontaneously within a period of hours. The mechanism of this reaction is not known. Such patients should be closely observed and vital signs checked. If the drug is reinstituted, it should be done with caution since these acute CNS manifestations may recur.

There have been instances of psychological and physical dependence on parenteral pentazocine in patients with a history of drug abuse, and rarely, in patients without such a history. (See DRUG ABUSE AND DEPENDENCE .)

Due to the potential for increased CNS depressant effects, alcohol should be used with caution in patients who are currently receiving pentazocine.

Pentazocine may precipitate opioid abstinence symptoms in patients receiving courses of opiates for pain relief.

In prescribing TALACEN for chronic use, the physician should take precautions to avoid increases in dose by the patient.

Myocardial Infarction.   As with all drugs, TALACEN should be used with caution in patients with myocardial infarction who have nausea or vomiting.

Certain Respiratory Conditions.   Although respiratory depression has rarely been reported after oral administration of pentazocine, the drug should be administered with caution to patients with respiratory depression from any cause, severely limited respiratory reserve, severe bronchial asthma and other obstructive respiratory conditions, or cyanosis.

Impaired Renal or Hepatic Function.   Decreased metabolism of the drug by the liver in extensive liver disease may predispose to accentuation of side effects. Although laboratory tests have not indicated that pentazocine causes or increases renal or hepatic impairment, the drug should be administered with caution to patients with such impairment.

Since acetaminophen is metabolized by the liver, the question of the safety of its use in the presence of liver disease should be considered.

Biliary Surgery.   Narcotic drug products are generally considered to elevate biliary tract pressure for varying periods following their administration. Some evidence suggests that pentazocine may differ from other marketed narcotics in this respect (i.e., it causes little or no elevation in biliary tract pressures). The clinical significance of these findings, however, is not yet known.

CNS Effect.   Caution should be used when TALACEN is administered to patients prone to seizures; seizures have occurred in a few such patients in association with the use of pentazocine although no cause and effect relationship has been established.

Carcinogenesis, Mutagenesis, Impairment of Fertility.   Carcinogenesis, mutagenesis, and impairment of fertility studies have not been done with this combination product.

Pentazocine, when administered orally or parenterally, had no adverse effect on either the reproductive capabilities or the course of pregnancy in rabbits and rats. Embryotoxic effects on the fetuses were not shown.

The daily administration of 4 mg/kg to 20 mg/kg pentazocine subcutaneously to female rats during a 14 day pre-mating period and until the 13th day of pregnancy did not have any adverse effects on the fertility rate.

There is no evidence in long-term animal studies to demonstrate that pentazocine is carcinogenic.

Pregnancy Category C.   Animal reproduction studies have not been conducted with TALACEN. It is also not known whether TALACEN can cause fetal harm when administered to pregnant women or can affect reproduction capacity. TALACEN should be given to pregnant women only if clearly needed. However, animal reproduction studies with pentazocine have not demonstrated teratogenic or embryotoxic effects.

Nonteratogenic Effects.   There has been no experience in this regard with the combination pentazocine and acetaminophen. However, there have been rare reports of possible abstinence syndromes in newborns after prolonged use of pentazocine during pregnancy.

Labor and Delivery.   Patients receiving pentazocine during labor have experienced no adverse effects other than those that occur with commonly used analgesics. TALACEN should be used with caution in women delivering premature infants. The effect of TALACEN on the mother and fetus, the duration of labor or delivery, the possibility that forceps delivery or other intervention or resuscitation of the newborn may be necessary, or the effect of TALACEN, on the later growth, development, and functional maturation of the child are unknown at the present time.

Nursing Mothers.   It is not known whether this drug is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when TALACEN is administered to a nursing woman.

Pediatric Use.   Safety and effectiveness in pediatric patients below the age of 12 have not been established.