Intranasal administration of naloxone by paramedics

Intranasal naloxone for the treatment of suspected heroin overdose

AIMS

This paper reviews available literature regarding the effectiveness, safety and utility of intranasal (i.n.) naloxone for the treatment of heroin overdose.

METHODS

Scientific literature in the form of published articles during the period January 1984 to August 2007 were identified by searching several databases including Medline, Cinahl and Embase for the following terms: naloxone, narcan, intranasal, nose. The data extracted included study design, patient selection, numbers, outcomes and adverse events.

RESULTS

Reports of the pharmacological investigation and administration of i.n. naloxone for heroin overdose are included in this review. Treatment of heroin overdose by administration of i.n. naloxone has been introduced as first-line treatment in some jurisdictions in North America, and is currently under investigation in Australia.

CONCLUSION

Currently there is not enough evidence to support i.n. naloxone as first-line intervention by paramedics for treatment of heroin overdose in the pre-hospital setting. Further research is required to confirm its clinical effectiveness, safety and utility. If proved effective, the i.n. route may be useful for drug administration in community settings (including peer-based administration), as it reduces risk of needlestick injury in a population at higher risk of blood-borne viruses. Problematically, naloxone is not manufactured currently in an ideal form for i.n. administration.

Intranasal delivery: physicochemical and therapeutic aspects

Interest in intranasal (IN) administration as a non-invasive route for drug delivery continues to grow rapidly. The nasal mucosa offers numerous benefits as a target issue for drug delivery, such as a large surface area for delivery, rapid drug onset, potential for central nervous system delivery, and no first-pass metabolism. A wide variety of therapeutic compounds can be delivered IN, including relatively large molecules such as peptides and proteins, particularly in the presence of permeation enhancers. The current review provides an in-depth discussion of therapeutic aspects of IN delivery including consideration of the intended indication, regimen, and patient population, as well as physicochemical properties of the drug itself. Case examples are provided to illustrate the utility of IN dosing. It is anticipated that the present review will prove useful for formulation scientists considering IN delivery as a delivery route.

Effect of opioid antagonist naloxone on maternal motivation in albino rats

We studied the effect of nonselective antagonist of opioid receptor naloxone on the behavior of albino female rats on days 4-6 after delivery. Intraperitoneal injection of naloxone (5 mg/kg) significantly stimulated maternal reactions (increased the number of approaches to pups, decreased the latency of their transfer into new location). Intranasal naloxone (1 mg/kg) produced similar changes. Naloxone in intraperitoneal dose of 1 mg/kg and intranasal dose of 0.2 mg/kg virtually did not modify maternal behavior.

Best evidence topic report. Intranasal naloxone in suspected opioid overdose

A short cut review was carried out to establish whether intransasal naloxone is effective in suspected opiate overdose. 596 papers were screened, of which eight presented the best evidence to answer the clinical question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these best papers are tabulated. The clinical bottom line is that it is likely that intranasal Naloxone is a safe and effective first line prehospital intervention in reversing the effects of an Opioid overdose and helping to reduce the risk of needle stick injury. A large, well conducted trial into it's usage is however required to confirm this.

Take-home naloxone to reduce heroin death

BACKGROUND

This paper reviews the relevant literature related to the distribution of take-home naloxone.

METHODS

A Medline search was conducted on articles published between January 1990 and June 2004 to identify scientific literature relevant to this subject. Those publications were reviewed, and from them other literature was identified and reviewed.

RESULTS

The prevalence, pathophysiology and circumstances of heroin overdose, and also bystander response are included in this review. Naloxone peer distribution has been instituted to varying degrees in the United States, Italy, Spain, Germany and the United Kingdom.

CONCLUSION

At this point the evidence supporting naloxone distribution is primarily anecdotal, although promising. Although the distribution of naloxone holds promise for further reducing heroin overdose mortality, problems remain. Naloxone alone may be insufficient in some cases to revive the victim, and cardiopulmonary resuscitation (CPR), especially rescue breathing, may also be needed. A second dose of naloxone might be necessary. Complications following resuscitation from overdose may infrequently need in-hospital care. Mortality from injecting without anyone else present will be unaffected by take-home naloxone. Take-home naloxone should be studied in a rigorous scientific manner.

Efficacy of intranasal naloxone as a needleless alternative for treatment of opioid overdose in the prehospital setting

Prehospital providers are at increased risk for blood-borne exposure and disease due to the nature of their environment. The use if intranasal (i.n.) medications in high-risk populations may limit this risk of exposure. To determine the efficacy of i.n. naloxone in the treatment of suspected opiate overdose patients in the prehospital setting, a prospective, nonrandomized trial of administering i.n. naloxone by paramedics to patients with suspected opiate overdoses over a 6-month period was performed. All adult patients encountered in the prehospital setting as suspected opiate overdose (OD), found down (FD), or with altered mental status (AMS) who met the criteria for naloxone administration were included in the study. i.n. naloxone (2 mg) was administered immediately upon patient contact and before i.v. insertion and administration of i.v. naloxone (2 mg). Patients were then treated by EMS protocol. The main outcome measures were: time of i.n. naloxone administration, time of i.v. naloxone administration, time of appropriate patient response as reported by paramedics. Ninety-five patients received i.n. naloxone and were included in the study. A total of 52 patients responded to naloxone by either i.n. or i.v., with 43 (83%) responding to i.n. naloxone alone. Seven patients (16%) in this group required further doses of i.v. naloxone. In conclusion, i.n. naloxone is a novel alternative method for drug administration in high-risk patients in the prehospital setting with good overall effectiveness. The use of this route is further discussed in relation to efficacy of treatment and minimizing the risk of blood-borne exposures to EMS personnel.

Naloxone in opioid poisoning: walking the tightrope

Acute opioid intoxication and overdose are common causes of presentation to emergency departments. Although naloxone, a pure opioid antagonist, has been available for many years, there is still confusion over the appropriate dose and route of administration. This article looks at the reasons for this uncertainty and undertakes a literature review from which a treatment algorithm is presented.

Comparison of Human Tracheal/Bronchial Epithelial Cell Culture and Bovine Nasal Respiratory Explants for Nasal Drug Transport Studies

Ten drug compounds with varying physicochemical properties and transporter substrate specificities were investigated to compare their in vitro permeabilities across bovine nasal respiratory explants and the EpiAirway system, both established models for the assessment of nasal drug absorption. Permeability across the bovine explants and EpiAirway correlated well with the partitioning behavior of compounds whose clogDC values were greater than 0. The permeabilities of all ten compounds were well-correlated between the two tissue models, with the permeability values through the EpiAirway tissues being approximately 10-fold higher than through the bovine explants due to the thickness differences between the models. For more lipophilic compounds, the in vitro permeabilities measured with both tissue systems were also predictive of the reported in vivo nasal bioavailabilities. Deviations from these correlations were observed for compounds reported to be substrates of p-glycoprotein or OCT transporters, and differences were also seen between the permeabilities measured in the tissue models for these compounds. Both models can be used to estimate the systemic bioavailability of moderately lipophilic compounds administered intranasally, while each may have particular advantages or disadvantages in estimating the bioavailability of drug compounds that are subject to local mucosal metabolism or to carrier-mediated uptake or efflux.

Adverse effects following the inadvertent administration of opioids to infants and children

Regardless of the clinical scenario in which they are administered, opioids can have adverse effects in infants and children. These adverse effects may be particularly problematic when opioids are inadvertently administered since the clinical signs and symptoms may not be readily attributed to opioids without an appropriate history. The authors present 3 clinical scenarios in which adverse effects occurred related to the inadvertent administration of opioids when: (1) acetaminophen with codeine were administered instead of acetaminophen, (2) a mother was breastfeeding while taking opioids, and (3) a fentanyl patch was placed on a superficial injury. A thorough history and physical examination combined with urine/plasma drug screening resulted in the identification of the problem and its effective therapy.

Randomised trial of intranasal versus intramuscular naloxone in prehospital treatment for suspected opioid overdose

OBJECTIVE

To determine the effectiveness of intranasal (IN) naloxone compared with intramuscular (IM) naloxone for treatment of respiratory depression due to suspected opiate overdose in the prehospital setting.

DESIGN

Prospective, randomised, unblinded trial of either 2 mg naloxone injected intramuscularly or 2 mg naloxone delivered intranasally with a mucosal atomiser.

PARTICIPANTS AND SETTING

155 patients (71 IM and 84 IN) requiring treatment for suspected opiate overdose and attended by paramedics of the Metropolitan Ambulance Service (MAS) and Rural Ambulance Victoria (RAV) in Victoria.

MAIN OUTCOME MEASURES

Response time to regain a respiratory rate greater than 10 per minute. Secondary outcome measures were proportion of patients with respiratory rate greater than 10 per minute at 8 minutes and/or a GCS score over 11 at 8 minutes; proportion requiring rescue naloxone; rate of adverse events; proportion of the IN group for whom IN naloxone alone was sufficient treatment.

RESULTS

The IM group had more rapid response than the IN group, and were more likely to have more than 10 spontaneous respirations per minute within 8 minutes (82% v 63%; P = 0.0173). There was no statistically significant difference between the IM and IN groups for needing rescue naloxone (13% [IM group] v 26% [IN group]; P = 0.0558). There were no major adverse events. For patients treated with IN naloxone, this was sufficient to reverse opiate toxicity in 74%.

CONCLUSION

IN naloxone is effective in treating opiate-induced respiratory depression, but is not as effective as IM naloxone. IN delivery of naxolone could reduce the risk of needlestick injury to ambulance officers and, being relatively safe to make more widely available, could increase access to life-saving treatment in the community.