Pentazo

For the relief of moderate to severe pain. Pentazocine may also be used for preoperativeor preanesthetic medication and as a supplement to surgical anesthesia.

Pentazocine is a benzomorphan derivative with mixed opioid agonist and antagonist actions. It alters perception of and response to pain and produces generalised CNS depression by binding to opiate receptors in the CNS and acting as a partial agonist/antagonist.

Depressant affects potentiated by alcohol, CNS depressants; concurrent use with fluoxetine may lead to diaphoresis, ataxia flushing and tremor associated with serotonin syndrome.

Physical dependence; sedation, dizziness, euphoria, lightheadedness, alterations of mood; respiratory depression; visual hallucinations, disorientation, confusion; hypertension, tachycardia, circulatory depression; shock; hypotension; nausea, vomiting, constipation; seizures, diaphoresis; rash; blood dyscrasias; local tissue damages (SC), muscle fibrosis (IM).

Safe use of Pentazocine during pregnancy (other than labor) has not been established. Animal reproduction studies have not demonstrated teratogenic or embryotoxic effects. However, Pentazocine should be administered to pregnant patients (other than labor) only when, in the judgment of the physician, the potential benefits outweigh the possible hazards. Patients receiving Pentazocine during labor have experienced no adverse effects other than those that occur with commonly used analgesics. Pentazocine should be used with caution in women delivering premature infants.

May precipitate withdrawal in narcotic addicts. Impaired respiratory, renal and hepatic function; morbidly obese patients; thyroid dysfunction; prostatic hyperplasia or urinary stricture; biliary tract impairment; adrenal insufficiency (including Addison’s disease); abdominal conditions. Elderly or debilitated patients; seizure-prone patients; children and infants (safety and efficacy not established in less than 1 yr); lactation. May impair ability to drive or operate machinery. Administer IM rather than SC (when frequent inj are needed) and inj sites should be varied.

Pediatric Use: The safety and efficacy of Pentazocine as preoperative or preanesthetic medication have been established in pediatric patients 1 to 16 years of age. Use of Pentazocine in these age groups is supported by evidence from adequate and controlled studies in adults with additional data from published controlled trials in pediatric patients. The safety and efficacy of Pentazocine as a premedication for sedation have not been established in pediatric patients less than one year old. Information on the safety profile of Pentazocine as a postoperative analgesic in children less than 16 years is limited.

Geriatric Use: Elderly patients may be more sensitive to the analgesic effects of Pentazocine than younger patients. Clinical data indicate that differences in various pharmacokinetic parameters of Pentazocine may exist between elderly and younger patients. Sedating drugs may cause confusion and oversedation in the elderly; elderly patients generally should be started on low doses of Pentazocine and observed closely.

This drug is known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function.

Opioid analgesics