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Talwin Side Effects

Generic Name: pentazocine

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

For the Consumer

Applies to pentazocine: injection solution

Along with its needed effects, pentazocine (the active ingredient contained in Talwin) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur while taking pentazocine:

  • Black, tarry stools
  • blistering, peeling, or loosening of the skin
  • chest pain
  • chills
  • cough
  • diarrhea
  • fast, pounding, or irregular heartbeat or pulse
  • fever
  • itching
  • joint or muscle pain
  • painful or difficult urination
  • red, irritated eyes
  • red skin lesions, often with a purple center
  • shakiness in the legs, arms, hands, or feet
  • sore throat
  • sores, ulcers, or white spots on the lips or in the mouth
  • swelling or puffiness of the face
  • swollen glands
  • trembling or shaking of the hands or feet
  • trouble breathing
  • unusual bleeding or bruising
  • unusual tiredness or weakness
Incidence not known
  • Blistering, crusting, irritation, itching, or reddening of the skin
  • blue-green to black skin discoloration
  • bluish lips or skin
  • blurred vision
  • burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
  • cold, clammy skin
  • confusion
  • cough
  • cracked, dry, or scaly skin
  • decrease in the frequency of urination
  • decrease in urine volume
  • depression
  • difficult or troubled breathing
  • difficulty in passing urine (dribbling)
  • dizziness
  • fainting
  • fast or slow heartbeat
  • fast, weak pulse
  • flushed skin
  • hardening or thickening of the skin
  • headache
  • increased sweating
  • irregular, fast, slow, or shallow breathing
  • lightheadedness
  • nervousness
  • pain, redness, or sloughing of the skin at the injection site
  • pale or blue lips, fingernails, or skin
  • pounding in the ears
  • rapid breathing
  • small lumps under the skin at the injection site
  • stinging at the injection site
  • sweating
  • swelling of the lower legs or arms
  • tightness in the chest
  • very slow breathing
  • weight gain

Some side effects of pentazocine may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common
  • False or unusual sense of well-being
  • nausea
  • vomiting
  • Change in taste
  • confusion about identity, place, and time
  • constricted, pinpoint, or small pupils (black part of the eye)
  • double vision
  • seeing double seeing, hearing, or feeling things that are not there
  • stomach cramps
  • trouble sleeping
  • uncontrolled eye movements
Incidence not known
  • Continuing ringing or buzzing or other unexplained noise in the ears
  • difficulty having a bowel movement (stool)
  • difficulty in focusing the eyes
  • disturbed dreams
  • drowsiness
  • dry mouth
  • excitement
  • hearing loss
  • irritability
  • relaxed and calm
  • sleepiness
  • trouble sleeping
  • weakness

For Healthcare Professionals

Applies to pentazocine: injectable solution

Nervous system

Nervous system side effects including sweating, dizziness, lightheadedness, hallucinations, sedation, euphoria, headache, confusion, and disorientation have been reported. Weakness, flushing, disturbed dreams, insomnia, and syncope have been reported infrequently. Tremor, chills, paresthesia, irritability, and excitement have been reported rarely.[Ref]


Gastrointestinal side effects including nausea and vomiting have been reported. Constipation has been reported infrequently. Abdominal distress, anorexia, and diarrhea have been reported rarely.[Ref]


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

Hematologic side effects including depression of the white blood cell count (especially granulocytes) and moderate transient eosinophilia have been reported.[Ref]


Hypersensitivity reactions including rash have been reported infrequently. Urticaria and edema of the face have been reported rarely. One instance of an apparent anaphylactic reaction has been reported.[Ref]


Dermatologic side effects including erythema multiforme, Stevens-Johnson syndrome, and toxic epidermal necrolysis have been reported rarely.[Ref]


Cardiovascular side effects including a decrease in blood pressure and tachycardia have been reported infrequently.[Ref]


Respiratory side effects including respiratory depression have rarely been reported.[Ref]


Other side effects including tinnitus have been reported.[Ref]


Ocular side effects including visual blurring and focusing difficulty have been reported infrequently.[Ref]


Psychiatric side effects including depression have been reported infrequently.[Ref]


Genitourinary side effects including urinary retention have rarely been reported.[Ref]


1. "Product Information. Talwin NX (pentazocine)." Sanofi Winthrop Pharmaceuticals, New York, NY.

Some side effects of Talwin may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.