No

Analgesic, Narcotic

Relief of moderate to severe pain; has also been used as a sedative prior to surgery and as a supplement to surgical anesthesia

C-IV

B; D (if used for prolonged periods or in high doses at term)

Hypersensitivity to pentazocine or any component, increased intracranial pressure (unless the patient is mechanically ventilated)

Use with caution in seizure-prone patients, acute myocardial infarction, patients undergoing biliary tract surgery, patients with renal and hepatic dysfunction, head trauma, increased intracranial pressure, and patients with a history of prior opioid dependence or abuse; pentazocine may precipitate opiate withdrawal symptoms in patients who have been receiving opiates regularly; injection contains sulfites which may cause allergic reaction; tolerance or drug dependence may result from extended use

>10%:

Central nervous system: Euphoria, drowsiness

Gastrointestinal: Nausea, vomiting

Neuromuscular & skeletal: Weakness

1% to 10%:

Cardiovascular: Hypotension

Central nervous system: Malaise, headache, restlessness, nightmares

Dermatologic: Rash

Gastrointestinal: Xerostomia

Genitourinary: Ureteral spasm

Ocular: Blurred vision

Respiratory: Dyspnea

<1%: Insomnia, CNS depression, sedation, hallucinations, confusion, disorientation, seizures may occur in seizure-prone patients, increased intracranial pressure, palpitations, bradycardia, peripheral vasodilation, pruritus, antidiuretic hormone release, GI irritation, constipation, biliary tract spasm, urinary tract spasm, tissue damage and irritation with I.M./S.C. use, miosis, histamine release, physical and psychological dependence

Symptoms of overdose include drowsiness, sedation, respiratory depression, coma

Naloxone 2 mg I.V. (0.01 mg/kg for children) with repeat administration as necessary up to a total of 10 mg

CYP2D6 enzyme substrate

Increased effect/toxicity with tripelennamine (can be lethal), CNS depressants (phenothiazines, tranquilizers, anxiolytics, sedatives, hypnotics, or alcohol)

Store at room temperature, protect from heat and from freezing; I.V. form is incompatible with aminophylline, amobarbital (and all other I.V. barbiturates), glycopyrrolate (same syringe), heparin (same syringe), nafcillin (Y-site)

Binds to opiate receptors in the CNS, causing inhibition of ascending pain pathways, altering the perception of and response to pain; produces generalized CNS depression; partial agonist-antagonist

Onset of action: Oral, I.M., S.C.: Within 15-30 minutes; I.V.: Within 2-3 minutes

Duration: Oral: 4-5 hours; Parenteral: 2-3 hours

Protein binding: 60%

Metabolism: Large first-pass effect; metabolized in liver via oxidative and glucuronide conjugation pathways

Bioavailability, oral: ~20%; increased to 60% to 70% in patients with cirrhosis

Half-life: 2-3 hours; increased with decreased hepatic function

Elimination: Smaller amounts excreted unchanged in urine

Children: I.M., S.C.:

5-8 years: 15 mg

8-14 years: 30 mg

Children >12 years and Adults: Oral: 50 mg every 3-4 hours; may increase to 100 mg/dose if needed, but should not exceed 600 mg/day

Adults:

I.M., S.C.: 30-60 mg every 3-4 hours, not to exceed total daily dose of 360 mg

I.V.: 30 mg every 3-4 hours

Dosing adjustment in renal impairment:

Cl_cr 10-50 mL/minute: Administer 75% of normal dose

Cl_cr <10 mL/minute: Administer 50% of normal dose

Dosing adjustment in hepatic impairment: Reduce dose or avoid use in patients with liver disease

Alcohol: Additive CNS effect, avoid use

Relief of pain, respiratory and mental status, blood pressure

Drowsiness and euphoria are common; may cause restlessness or nightmares; may rarely cause confusion, depression, or hallucinations

Concurrent use with psychotropics may produce additive effects or toxicity; may cause withdrawal in patients currently dependent on narcotics

No information available to require special precautions

No effects or complications reported

If self-administered, use exactly as directed (do not increase dose or frequency); may cause physical and/or psychological dependence. While using this medication, do not use alcohol and other prescription or OTC medications (especially sedatives, tranquilizers, antihistamines, or pain medications) without consulting prescriber. Maintain adequate hydration (2-3 L/day of fluids unless instructed to restrict fluid intake). May cause hypotension, dizziness, drowsiness, impaired coordination, or blurred vision (use caution when driving, climbing stairs, or changing position - rising from sitting or lying to standing, or when engaging in tasks requiring alertness until response to drug is known); nausea, vomiting, loss of appetite, or dry mouth (frequent mouth care, small frequent meals, chewing gum, or sucking lozenges may help); constipation (increased exercise, fluids, or dietary fruit and fiber may help - if constipation remains an unresolved problem, consult prescriber about use of stool softeners). Report persistent dizziness or headache; excessive fatigue or sedation; changes in mental status; changes in urinary elimination or pain on urination; weakness or trembling; blurred vision; or shortness of breath. Pregnancy/breast-feeding precautions: Inform prescriber if you are or intend to be pregnant. Consult prescriber if breast-feeding.

Observe patient for excessive sedation, respiratory depression, implement safety measures, assist with ambulation; observe for narcotic withdrawal

Injection, as lactate: 30 mg/mL (1 mL, 1.5 mL, 2 mL, 10 mL)

Tablet: Pentazocine hydrochloride 50 mg and naloxone hydrochloride 0.5 mg

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