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Talwin Side Effects

Generic name: pentazocine

Medically reviewed by Last updated on Oct 29, 2022.

Note: This document contains side effect information about pentazocine. Some dosage forms listed on this page may not apply to the brand name Talwin.

Applies to pentazocine: oral tablets.


    Concomitant Use with Benzodiazepines or Other CNS Depressants
  • Concomitant use of opiates with benzodiazepines or other CNS depressants, including alcohol, may result in profound sedation, respiratory depression, coma, and death.416 417 418 700 701 702 703

  • Reserve concomitant use of opiate analgesics and benzodiazepines or other CNS depressants for patients in whom alternative treatment options are inadequate; use lowest effective dosages and shortest possible duration of concomitant therapy and monitor closely for respiratory depression and sedation.700 703 (See Specific Drugs and Laboratory Tests under Interactions.)


FDA approved a REMS for pentazocine to ensure that the benefits outweigh the risk. The REMS may apply to one or more preparations of pentazocine and consists of the following: medication guide and elements to assure safe use. See the FDA REMS page ([Web]).

Side effects include:

Dizziness, lightheadedness, euphoria, sedation, nausea.

For Healthcare Professionals

Applies to pentazocine: injectable solution.


The most commonly occurring adverse reactions have included nausea, dizziness or lightheadedness, vomiting, and euphoria.


Postmarketing reports: Soft tissue induration, nodules and cutaneous depressions at injection sites; ulceration (sloughing), severe sclerosis of the skin and subcutaneous tissues and, rarely, underlying muscle; diaphoresis, sting on injection, flushed skin including plethora, dermatitis including pruritus[Ref]


Postmarketing reports: Anaphylaxis, facial edema, toxic epidermal necrolysis[Ref]

Nervous system

Serotonin syndrome has been reported during concomitant use of opioids with serotonergic drugs.[Ref]

Postmarketing reports: Dizziness, lightheadedness, sedation, headache, weakness, flushing, syncope, tremor, paresthesia


Postmarketing reports: Serotonin syndrome[Ref]


Postmarketing reports: Depression, euphoria, confusion, disorientation, disturbed dreams, insomnia, irritability, excitement, hallucinations[Ref]


Postmarketing reports: Respiratory depression, dyspnea, transient apnea (in infants whose mothers received this drug during labor)[Ref]


Postmarketing reports: Circulatory depression, shock, hypertension, tachycardia, syncope[Ref]


Postmarketing reports: Nausea, vomiting, constipation, dry mouth, taste alteration, diarrhea and cramps[Ref]


Depression of the white blood cell count is usually reversible.[Ref]

Postmarketing reports: Depression of the white blood cell count (especially granulocytes), moderate transient eosinophilia[Ref]


Postmarketing reports: Tinnitus, chills[Ref]


Postmarketing reports: Visual blurring and focusing difficulty, blurred vision, diplopia, miosis, nystagmus[Ref]


Postmarketing reports: Urinary retention, alteration in rate or strength of labor contractions[Ref]



Postmarketing reports: Adrenal insufficiency, Androgen deficiency

Cases of adrenal insufficiency have been reported with opioid use, generally use greater than 1 month. Cases of androgen deficiency have been reported with chronic opioid use.


1. "Product Information. Talwin NX (pentazocine)." Sanofi Winthrop Pharmaceuticals (2001):

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.