Naloxone (Narcan)

Question 1

Naloxone (Narcan): Classification

Answer 1

1. Narcotic antagonist

2. Diagnostic agent

Question 2

Naloxone (Narcan): Pharmacodynamic

Answer 2

1. Reverses effects of opioids including respiratory depression, sedation, hypotension
2. Antagonizes the opioid effects by competing for the same receptor sites, especially the opioid mu receptor
3. Also shown to bind to all three opioid receptors (mu, kappa and gamma) with the strongest binding to mu receptor

Question 3

Naloxone (Narcan): Pharmacokinetics

Answer 3

1. Intravenous
   - Onset: 1 minute
   - Peak: Unknown
   - Half-life: 1 hour up to 3 hours
   - Duration: 45 minutes

Question 4

Naloxone (Narcan): Indications

Answer 4

1. To reverse respiratory depression/depressed mental status secondary to actual or suspected narcotic use - examples of other narcotics: Demerol, Heroine, Codeine, Oxymorphone (Numorphan), Hydromorphone (Dilaudid), Diphenoxylate (Lomotil), Propoxyphene (Darvon), and Pentazocine (Talwin)

Question 5

Naloxone (Narcan): Contraindications

Answer 5

1. Allergy or known hypersensitivity to naloxone

Question 6

Naloxone (Narcan): Precautions

Answer 6

1. Be prepared for patient combativeness
2. In the chronic narcotic abuser, may precipitate withdrawal symptoms
3. Miscarriage or premature labour
4. Very short half-life; monitor patient closely and prepare to re-dose if deterioration occurs

Question 7

Naloxone (Narcan): Adverse Effects

Answer 7

1. Reversal of narcotic effect and combativeness
2. Signs and symptoms of severe drug withdrawal
3. Hypotension, hypertension
4. N/V, sweating, tachycardia
5. Ventricular fibrillation, asystole

Question 8

Naloxone (Narcan): Dosage

Answer 8

1. 0.8 mg sc if patient has reasonable perfusion
2. 0.4 mg IM; repeat q5 min as needed to 0.8 mg. Call EPOS for any further dosing
3. 0.1-0.4 mg is the usual IV dose: titrate to restore respiration and adequate level of consciousness to maintain airway. If ineffective repeat at 0.4 mg does up to 2 mg; larger doses to 10 mg may be required in rare overdose situations - contact EPOS for orders
4. 2 mg IV/IO by ACP/ITT/CCP if cardiac arrest secondary to suspected opioid overdose. Repeat up to 4 mg. Call EPOS if more than 4 mg is initially needed - ACP/ITT/CCP only
5. 4 mg may be given by ET(diluted in Normal Saline to a total volume of 10 ml) for cardiac arrest secondary to suspected narcotic overdose where there is no IV/IO access

Question 9

Naloxone (Narcan): Pediatric

Answer 9

1. 0.01 mg/kg slow IV/IO/SC/IM. Maximum initial dose 0.4 mg. May be repeated q 3-5 minutes to a maximum dose of 2 mg. Contact EPOS if not effective for further dosing instructions

Question 10

Naloxone (Narcan): Special Notes

Answer 10

1. Naloxone is generally considered a very safe drug - however, potentially life-threatening problems (such as status seizures and asystole), occur in about 1% of patients treated. It is further hypothesized that these episodes may be related to an acute withdrawal syndrome associated with reversal of opioid-induced epinephrine blockade rather than to a direct intrinsic effect of naloxone
2. Administration of naloxone to a comatose patient who has taken other medications/substances may result in a partial elevation of the GCS and/or combativeness
3. Naloxone administration may be titrated to improve spontaneous respiratory effort without complete reversal of opiate effects