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Pharmacologic class: Opioid agonist-antagonist
Therapeutic class: Opioid analgesic
Controlled substance schedule IV Pregnancy risk category C
Alters perception of and emotional response to pain by binding with opioid receptors in brain, causing CNS depression. Also exerts antagonistic activity at opioid receptors, which reduces risk of toxicity, drug dependence, and respiratory depression.
Injection: 1 mg/ml, 2 mg/ml
Nasal spray: 10 mg/ml
Indications and dosages
➣ Moderate to severe pain
Adults: 1 to 4 mg I.M. q 3 to 4 hours as needed, not to exceed 4 mg/dose. Or 0.5 to 2 mg I.V. q 3 to 4 hours as needed. With nasal spray, 1 mg (one spray in one nostril) q 3 to 4 hours, repeated in 60 to 90 minutes if needed.
➣ Labor pains
Adults: 1 to 2 mg I.V. or I.M., repeated after 4 hours as needed
➣ Preoperative anesthesia
Adults: 2 mg I.M. 60 to 90 minutes before surgery
➣ Balanced anesthesia
Adults: 2 mg I.V. shortly before anesthesia induction, or 0.5 to 1 mg I.V. in increments during anesthesia
• Renal or hepatic impairment
• Elderly patients
• Symptomatic relief of ureteral colic
• Hypersensitivity to drug
Use cautiously in:
• head injury, ventricular dysfunction, coronary insufficiency, respiratory disease, renal or hepatic dysfunction
• history of drug abuse.
• Make sure solution is clear and free of particulates before giving.
• When using nasal spray, insert tip of the sprayer about ¼″ into nostril, point tip backwards, and administer one spray.
• Be aware that I.V. route is preferred for severe pain.
☞ Know that drug may cause infant respiratory distress in neonate of pregnant patient, especially if given within 2 hours of delivery.
CNS: drowsiness, sedation, dizziness, tremor, irritability, syncope, stimulation
CV: hypertension, hypotension, palpitations, bradycardia, tachycardia, extrasystole, arrhythmias
EENT: blurred vision, nasal congestion or dryness, dry or sore throat
GI: nausea, vomiting, constipation, epigastric distress, dry mouth, GI obstruction
GU: urinary retention or hesitancy, dysuria, early menses, decreased libido, erectile dysfunction
Hematologic: hemolytic anemia, hypoplastic anemia, thrombocytopenia, agranulocytosis, leukopenia, pancytopenia
Respiratory: thickened bronchial secretions, chest tightness, wheezing
Skin: urticaria, rash, diaphoresis
Other: increased or decreased appetite, weight gain, local stinging, anaphylactic shock, hypersensitivity reaction (with I.V. use)
Drug-drug. CNS depressants: additive CNS effects
Drugs-herbs. Kava, St. John's wort, valerian: increased CNS depression
Drug-behaviors. Alcohol use: additive CNS effects
• Monitor respiratory status closely, especially after I.V. administration.
• Watch for signs and symptoms of withdrawal in long-term use and in opioid-dependent patients.
• Assess elderly patient closely for sensitivity to drug.
• Teach patient how to use nasal spray properly.
• Emphasize importance of using drug exactly as prescribed.
• Caution patient that drug may be habit-forming.
• Advise patient to avoid driving and other hazardous activities until he knows how drug affects concentration and alertness.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs and behaviors mentioned above.