(Pentazocine Injection BP 30 mg/ml)
Each ml contains:
Pentazocine BP 30 mg (present as lactate)
Water for injections BP q.s.
The major effect of Pentazocine is exerted on the CNS and smooth muscle. The CNS effects correspond to those of the opioids, namely analgesia, sedation and respiratory depression. The agonistic effects of Pentazocine are presumably exerted at the k and d receptors. Pentazocine also demonstrates a weak opioid antagonistic activity.
Pentazocine unlike other morphine-like opioids causes an increase in blood pressure and heart rate in high doses. In patients with coronary artery disease (intravenously administered) Pentazocine elevates the means aortic pressure, left ventricular enddiastolic and mean pulmonary artery pressures, resulting in an increase in cardiac work. This is probably because of the rise in catecholamine concentrations in the plasma. Low doses of Pentazocine have the same effects on the gastro-intestinal tract as those of the opioids, with less elevation of biliary pressure than equianalgesic doses of morphine.
Pentazocine is well absorbed from the gastrointestinal tract, subcutaneous and intramuscular sites. Peak values after intramuscular administration are reached after 15 to 60 minutes and the plasma half-life is 2 to 3 hours. Extensive metabolism in the liver and the individual variation in metabolism could account for variability of analgesic response.
Post operative pain.
Chronic, moderate to severe pain.
It is contraindicated in children under three years of age: Since clinical experience in children is limited administration to children is not recommended.
Pentazocine is contra-indicated in respiratory depression, especially in the pressure of cyanosis and excessive bronchial secretions.
It is also contra-indicated in acute alcoholism, after biliary operations, in heart failure due to chronic lung disease.
Pentazocine should be given with caution to patients prone to seizures.
In cases of liver disease or cirrhosis there is an enhanced availability and the dose should be decreased.
May precipitate withdrawal symptoms in patients who have recently used narcotic analgesics.
Pilat should be used with care in patients with increased intracranial pressure and/or head injuries, or in patients with porphyria.
Pilat may cause physical and psychological dependence. Patients with a history of dependence should be closely supervised. Withdrawal symptoms may occur, even in newborns after prolonged administration during pregnancy.
Because of the possibility of incompatibility it should not be mixed with diazepam, aminophyllin,chlordiazepoxide or soluble barbiturates.
Pilat should be used with caution in shock, in reduced doses in elderly and debilitated patients, in hypothyroidism, adrenocortical insufficiency, impaired liver function and prostatic hypertrophy.
It should further be used with caution in patients with inflammatory bowel disorders, patients using monoamine-oxidase inhibitors or within 14 days of stopping such treatment.
It should also be used with caution during labour, especially in women delivering premature infants, as Pilat may cause respiratory depression in the new-born.
The use of this medicine may lead to drowsiness and impaired concentration which may be aggravated by simultaneous intake of alcohol or other central nervous system depressant agents.
Patients should be warned against taking charge of vehicles or machinery or performing potentially hazardous tasks where loss of concentration may lead to accidents.
DOSAGE AND DIRECTIONS FOR USE
30 to 60 mg l.M. or S.C. every 3 to 4 hours, 30 mg I.V. Not more than 360 mg should be given daily to adults.
(6 to 12years) 1 mg per kg body-mass I.M. or S.C. every 3 to 4 hours, 500 µg/kg body-mass I.V.
SIDE EFFECTS AND SPECIAL PRECAUTIONS
The most common side-effects are sedation followed by sweating, dizziness and light-headedness. Nausea, vomiting, dry mouth, constipation, headache flushing of the skin, disorientation, raised intracranial pressure, transient hypertension, mood changes, nightmares, anxiety, weird thoughts, hallucinations, paraesthesia, pruritus, biliary tract spasm and urinary retention have also been reported at does above 60 mg. Marked respiratory depression with increased blood pressure and tachycardia may occur. Other side effects are changed uterine contractions, insomnia, vision disturbances, transient eosinophilia, chills and allergic reactions. Injection site should be varied as multiple doses may cause extensive fibrosis of subcutaneous and muscular tissue. Large intravenous doses may cause grand mal convulsions.
KNOWN SYMPTOMS OF OVERDOSAGE AND PARTICULARS OF ITS TREATMENT
See side effects and special precautions. Respiratory depression is antagonized by naloxone 400 µg given I.V., I.M. or S.C. and repeated at intervals of 2 to 3 minutes if necessary. Assisted respiration may be necessary. Other treatment should be symptomatic and supportive.
Store in a cool, dark & dry place.
10 printed clear glass ampoules of 1 ml are packed in a plastic tray. Each such plastic tray is packed in individual printed carton along with a leaflet.
Manufactured in India by
515, M.I.E., Bahadurgarh
May & Baker Nigeria PLC
3/5, Sapara Street, Industrial Estate,
P.M.B. 21049, IKEJA.