Pentazocine

Narcotic Analgesic · Opioid analgesic

Indications

Moderate to severe pain.

Dosage

ORAL: Adults: 25-100 mg three to four hourly after meals. Children: 6-12 yr, 25 mg 3-4 hourly. Under 6 yr, Not recommended. INJECTION: Adults: 30-60 mg IM or SC or IV three or four hourly. Children: Under 1 yr, not recommended; 1-12 yr, max single dose 1 mg/kg body weight IM or SC or 0.5 mg/kg body weight IV.

Administration

IM: Rotate injection site; avoid intra-arterial injection. Other: Rotate injection site for SC use; avoid SC use unless absolutely necessary (may cause tissue damage); avoid intra-arterial injection. Stability: Store at 20°C-25°C. Do not freeze. Protect from light.

Adverse Effects

Sedation, dizziness, nausea. Psychotomimetic effects, vomiting, sweating.

Risk Factor (Pregnancy/Lactation)

Pregnancy: Positive evidence of risk: Use only when no safer alternative exists for a serious problem. Lactation: Caution advised or effect undetermined. Contraindications: Respiratory depression, raised intracranial pressure, head injury or pathological brain conditions, acute asthma, heart failure, secondary to chronic lung disease, porphyria. Narcotic dependence, acute alcoholism. Precautions: Impaired renal, hepatic or respiratory function. History of seizures, phaeochromocytoma, recent MI, hypothyroidism, adrenocortical insufficiency, prostatic hypertrophy, IBS, cholecystitis, pancreatitis, unidentified abdominal pain. Conditions where altered vascular resistance or BP is undesirable. Risk of tolerance and dependence. Elderly.

Interactions

MAOIs, narcotics, alcohol, smoking, CNS depressants.

Advice to Patient

If you are self-administering injection of this medication, follow directions for administration and disposal of needles as prescribed. If constipation is unrelieved in few days, consult prescriber for suitable laxative or stool-softener. Contact prescriber if there is difficulty in breathing, increased fatigue, sedation, constant dizziness or headache, changes in urinary pattern, pain on urination, changes in mental status, blurred vision, weakness, trembling, skin rash, itching. Take sufficient amount of fluids (2-3 litres per day) to maintain hydration, unless restricted by the prescriber. Avoid alcohol during therapy. Do not take OTC medications especially tranquilizers, sedatives, antihistamines, pain medications without consulting prescriber. Change position slowly when rising from sitting or lying position.

Pharmacokinetics

Onset: Oral: 15-30 mins. IM: 10-20 mins. Duration: 3 hrs. Absorption: Well absorbed from the GI tract. Metabolism: Hepatic. Bioavailability: Oral: Low. Half-life elimination: Oral: 2-3 hrs. IM: 2-5 hrs. Time to peak, plasma: Oral: 1-3 hrs. IM: 15 mins-1 hr. Excretion: Urine (mainly). Faeces (small amounts).

Brands with this active ingredient

• Entapin
• Eroflex
• Omsis
• P-Zoc
• Paingon
• Pantagon
• Pantasafe
• Pantasafe Injection
• Pantasyn
• Pentacin
• Pentafen
• Pentagesic
• Pentagon
• Pentazogon
• Segon

Compiled by Healify Pharmacy from published drug references. How we compile it →

Always consult a pharmacist or doctor.