This medication relieves moderate to severe pain. It is an opioid (narcotic) analgesic. It works in the brain and nervous system to decrease pain.  

Contraindicated in patients with head injury, increased blood pressure or pulmonary hypertension, patients dependent on opioids, heart failure, respiratory depression, heart attack and raised intracranial pressure. It should also not be used for a long time or in increased amounts at term during pregnancy.

Adult: 50-100 mg every 3 to 4 hrs; max 600 mg daily.
Child: 6 to12 yr: As hydrochloride: 25 mg every 3 to 4 hr.

It comes as a solution for injection, to be administered by a healthcare provider into the vein or large muscle.

• It may cause drowsiness or dizziness. Avoid driving or handling of machines while taking this drug.

• Avoid drinking alcohol or taking other medications that cause drowsiness while using this medication.

• It may cause allergic reaction if it contains sulfides.

• Inform your doctor about previous dental treatment.

• Caution needed for elderly people.

•  Heart: Circulatory depression, high blood pressure, shock, fast heart rate.
•  Central Nervous System: Confusion, depression, disorientation, disturbed dreams, dizziness, excitement, faintness, hallucinations, headache, sleeplessness, irritability, light-headedness, muscle tremor, tingling, sedation, temporary loss of consciousness, tremor, weakness.
•  Skin: Inflammation, including itching, excessive sweating, flushed skin.
•  Eye and ENT: Double vision, constriction of the pupil, involuntary eye movement, perception of sound, visual blurring, and focusing difficultly.
•  Gastrointestinal: Constipation, cramps, diarrhea, dry mouth, nausea, taste alteration, vomiting.
•  Blood: High concentration of eosinophils decrease in the number of granulocytes.
•  Skin: Subcutaneous depression, nodules, severe stiffness, soft tissue induration, sting on injection, and ulceration at injection sites.
•  Respiratory: Difficulty in breath, respiratory depression, transient sleep disorder in newborns whose mothers received parenteral pentazocine during labor.
•  Miscellaneous: Allergic reactions, alterations in rate or strength of uterine contractions during labor, chills, urinary retention, unusual weakness.

Change the injection sites, avoid abrupt withdrawal.

Store Pentazocine at room temperature, 15 and 30 degrees C. Store it in an airtight container.