Pentazocine and naloxone is available by the brand name of Talwin-NX. It is a combination of Pentazocine which is an opioid analgesic and naloxone. Naloxone is used to reduce the addiction potential of pentazocine.

Indications of Pentazocine and Naloxone (Talwin-NX):

• Pain management:

  • It is used for the management of severe pain requiring an opioid analgesic and for which alternative treatments are inadequate.
  • Limitations of use: Reserve for use in patients in whom alternative treatment options (eg, nonopioid analgesics) are ineffective, not tolerated, or would be otherwise inadequate to provide sufficient management of pain.

Pentazocine and naloxone (Talwin-NX) dose in Adults

Pentazocine and naloxone (Talwin-NX) dose in Pain management:

• One tablet (pentazocine 50 mg/naloxone 0.5 mg) per oral every 3 to 4 hours;
• may increase to 2 tablets (pentazocine 100 mg/naloxone 1 mg) if needed.
• Maximum daily dose: 12 tablets (pentazocine 600 mg/naloxone 6 mg) per day.

• Discontinuation of therapy:

  • Gradual tapering should be done when discontinuing chronic opioid therapy..
  • Proposed schedules range from slow (eg, 10% reductions per week) to rapid (eg, 25% to 50% reduction every few days).
  • Tapering schedules should be individualized to minimize opioid withdrawal while considering patient-specific goals and concerns as well as the pharmacokinetics of the opioid being tapered.
  • Long term therapy for years needs slower tapering while patients experiencing severe adverse reactions need more rapid tapering.
  • Slow tapering should be done with withdrawal symptoms, alterations may include increasing the interval between dose reductions, decreasing daily dose reduction, pausing the taper and restarting when the patient is ready, and the combination of an alpha-2 agonist (eg, clonidine) to blunt withdrawal symptoms.
  • During the tapering, non-opioids should be used to control pain and withdrawal symptoms.

Pentazocine and naloxone (Talwin-NX) dose in Childrens

Refer to adults dosing.

Pregnancy Risk Category: C

• [US Boxed Warning]
• Long-term opioid therapy can lead to neonatal opioid withdrawal syndrome, which can be fatal if it is not treated properly.
• If long-term opioid therapy is required in pregnancy, the patient should be informed about the potential for neonatal opioid withdrawal syndrome (Neonatal Opioid Withdrawal Syndrome) and the appropriate management options.
• For more information, contact individual agents.

Use of pentazocine or naloxone during breastfeeding

• Breast milk contains pentazocine.
• It is not known if breast milk secretes Naloxone.
• According to the manufacturer's instructions, the decision about whether to continue breastfeeding or stop breastfeeding during therapy is based on the risks and benefits to the infant as well as the benefits to the mother.
• Contact individual agentsPentazocineand naloxone)

Dose adjustment in renal disease:

• There are no dosage adjustments provided in the manufacturer’s labeling. Use with caution.
• The following recommendations have been used by some clinicians based on pentazocine component:

  • GFR ≥50 mL/minute:

    • No dosage adjustment necessary

  • GFR 10 to 50 mL/minute:

    • Administer 75% of normal dose

  • GFR <10 mL/minute:

    • Administer 50% of normal dose

Dose adjustment in liver disease:

There are no dosage adjustments provided in the manufacturer's labeling. Use with caution.

Side effects of Pentazocine and Naloxone (Talwin-NX):

• Cardiovascular:

  • Circulatory Depression
  • Facial Edema
  • Flushing
  • Hypertension
  • Hypotension
  • Syncope
  • Tachycardia

• Central Nervous System:

  • Central Nervous System Depression
  • Chills
  • Confusion
  • Disorientation
  • Dizziness
  • Drowsiness
  • Drug Dependence
  • Euphoria
  • Excitement
  • Hallucination
  • Headache
  • Increased Intracranial Pressure
  • Insomnia
  • Irritability
  • Nightmares
  • Paresthesia
  • Sedation
  • Seizure
  • Withdrawal Syndrome

• Dermatologic:

  • Dermatitis
  • Diaphoresis
  • Erythema Multiforme
  • Pruritus
  • Skin Rash
  • Stevens-Johnson Syndrome
  • Toxic Epidermal Necrolysis
  • Urticaria

• Gastrointestinal:

  • Abdominal Distress
  • Anorexia
  • Biliary Tract Spasm
  • Constipation
  • Diarrhea
  • Nausea
  • Vomiting
  • Xerostomia

• Genitourinary:

  • Urinary Retention

• Hematologic & Oncologic:

  • Agranulocytosis (Rare)
  • Decreased White Blood Cell Count
  • Eosinophilia

• Hypersensitivity:

  • Anaphylaxis

• Neuromuscular & Skeletal:

  • Tremor
  • Weakness

• Ophthalmic:

  • Blurred Vision
  • Miosis

• Otic:

  • Tinnitus

• Respiratory:

  • Respiratory Depression (Rare)

Contraindications to Pentazocine and naloxone (Talwin-NX):

• Hypersensitivity to pentazocine, Naloxone or any other component of the formulation (eg, anaphylaxis).
• GI obstruction/ paralytic ileus
• Bronchitis, acute or severe
• Grave respiratory depression.

Warnings and precautions

• Cardiovascular effects

  • Pentazocine should not be used in MI because it can increase systemic and/or pulmonary arterial pressures and systemic resistance.

• CNS effects

  • CNS depression can cause impairments in mental and physical abilities. It is important to warn patients not to drive or operate machinery.
  • Some patients have experienced confusion, disorientation and visual hallucinations. However, it usually resolves in a matter of hours.

• Constipation

  • Constipation can occur with unstable angina or post-myocardial injury. Therefore, preventive measures such as stool softener and increased fiber are recommended.

• Respiratory depression [US Boxed Warning]

  • Respiratory depression is a serious condition that requires close monitoring. Carbon dioxide retention can increase the sedating effects associated with opioids.

• Conditions abdominales:

  • Patients with acute abdominal conditions may not be diagnosed or treated appropriately.

• Insufficiency of the adrenal glands:

  • Patients with adrenal insufficiency (Addison disease) should be cautious.
  • Long-term therapy can help with mood disorder, osteoporosis and sexual dysfunction caused by secondary hypogonadism.

• Insufficiency of the biliary tract:

  • Patients with biliary dysfunction (including acute pancreatitis) should be cautious. It may cause constriction to the sphincter.

• Bowel disease

  • Patients with inflammatory or obstructional bowel disease should be cautious.

• CNS depression/coma:

  • It should be avoided in patients suffering from CNS or come depression.

• Delirium tremens:

  • Patients with delirium-tremens should be taken with caution

• Use of ethanol:

  • Be aware that there is a greater risk of CNS depressant side effects.

• Head trauma

  • It should not be used if there is a head injury, intracranial lesion, or elevated intracranial Pressure.

• Hepatic impairment

  • Patients with hepatic impairment should be cautious.

• Mental health conditions

  • Regular monitoring is necessary for depression, anxiety disorders and post-traumatic stress disorder (OPD) due to the increased risk of opioid abuse disorder.

• Obesity:

  • Patients who are severely obese should be taken with caution

• Porphyria

  • Patients with a history porphyria should be cautious as it may worsen the condition.

• Prostatic hyperplasia/urinary restriction:

  • Patients with prostatic hyperplasia or urinary stricture should be cautious.

• Psychosis:

  • Patients with toxic psychosis should be treated with caution.

• Renal impairment

  • Patients with impaired renal function should be cautious.

• Respiratory disease

  • It is not recommended to be used in COPD, cor pulmonale, patients with reduced respiratory reserve, hypoxia or hypercapnia, as well as those who have preexisting respiratory depression.
  • These patients may prefer nonopioid analgesics.

• Seizures:

  • Preexisting seizures may be exacerbated or caused by therapy. Therefore, it is important to use it with caution.

• Sleep-disordered breathing

  • This should be avoided in severe or moderate sleep-disordered sleeping and used sparingly with other risk factors, such as obesity and heart failure.

• Thyroid dysfunction:

  • Patients with thyroid dysfunction should be cautious.

Pentazocine and naloxone: Drug Interaction

Note: Drug Interaction Categories:

• Risk Factor C: Monitor When Using Combination
• Risk Factor D: Consider Treatment Modification
• Risk Factor X: Avoid Concomitant Use

Monitoring parameters:

• BP
• Mental and respiratory health
• Bowel function
• Pain relief
• Signs and symptoms of abuse, misuse, or addiction
• Signs and symptoms of hypogonadism/hypoadrenalism

Alternate suggestions:

• Before treatment, and once per year, urine drug testing

• Chronic pain (end-of life or palliative care), active cancer treatment, sickle cells disease or medication-assisted opioid use disorder treatment):

  • Within one month of beginning treatment, evaluate the risks and benefits of opioid therapy. 
  • You should evaluate the risks and benefits of opioid therapy every three months, or more often if there is a higher risk of overdose.
• Clinicians should review the state prescription drug monitoring program data (PDMP) before initiation and every so often during therapy.

How to Administer Pentazocine and naloxone (Talwin-NX):

See Pentazocine (Talwin)

Mechanism of action of Pentazocine and naloxone:

Pentazocine:

• It acts as an agonist for kappa and partial agonist for mu opiate receptors in the CNS.
• It alters the perception and response of pain and inhibits the ascending pain pathways.
• This produces analgesia and respiratory depression and sedation similar in effect to opioids.

Naloxone:

• It acts as a pure opioid antagonist by competing for opioids and displacing them at opioid receptor sites in the CNS.
• It lacks pharmacologic action after oral administration due to its poor systemic absorption (low dose: 0.25 mg). 
• When administered parenterally, it inhibits pentazocine's actions.

See individual agents.

Pentazocine and naloxone Brand Names (International):

Talwin-NX

Pentazocine and naloxone Brand Names in Pakistan:

No Brands Available in Pakistan.