Overdose prevention education and naloxone prescribing complement the strategies employed in primary health care. Direct provision of the opioid-agonist therapies described above provide the primary care health provider the greatest opportunity to reduce the morbidity and mortality associated with opioid use disorders in particular, but also for alcohol use disorders. However, primary care health providers have a unique opportunity to support the health and prevent mortality for patients with less clear cut need, lack of access, or other barriers to entering formal specialty addiction treatment.
Naloxone is an opioid antagonist that acts by displacing opiates from receptor sites in the brain and reverses respiratory depression, a common cause of overdose deaths . Naloxone has not been shown to cause physical or psychological dependence or tolerance  nor has it been associated with increased drug use or risky behavior. Overdose due to opioids is typically a slow process taking place over the course of several hours during which the ability to administer naloxone and provide rescue breathing promptly is lifesaving . It is important to acknowledge that naloxone reverses only the effects of opioids. In the context of overdose related to multiple substances including opioids, it may still be sufficient to restore adequate respiration. If administered to an individual who is unresponsive due to a medical emergency not related to opioid toxicity, naloxone will have no effect.
While naloxone is most typically administered intravenously in the hospital or by medically trained first responders, it can be safely and effectively administered intramuscularly to simplify use. Administration of the injectable form via a nasal adaptor is becoming a wider practice although there is not presently a compatible FDA approved nasal adaptor or formulation specifically for intranasal use. Products, however, are in development . Recently a new autoinjector device, Evsio, was approved by the FDA. The product is handheld and when turned on provides verbal instruction to the user similar to automated defibrillators.
SAMHSA also recommends consideration be given to coprescribing naloxone to patients receiving opioid analgesics . For example, potential candidates to receive naloxone are patients undergoing a transition from one opioid treatment regimen to another, for whom it is medically necessary to take other potential respiratory depressants concurrently to manage other medical conditions, or who have respiratory or other illnesses increasing their susceptibility to respiratory depression. In addition by using screening and brief intervention tools (SBIRT), patients not previously recognized to be at risk for overdose can be identified. In these cases, overdose prevention and naloxone prescription form the basis of an appropriate brief intervention.
Primary health care providers are uniquely placed to address risk for overdose due to relapse to opioid use. Awareness of an individual’s history of substance use disorder affords the primary care provider the opportunity to assess the stability and durability of a patient’s recovery. A review of sober social supports, engagement in self-help, intensity and frequency of craving, and strategies for coping with cravings and external triggers can bolster an individual’s ability to sustain his or her recovery. In the case of opioids in particular, relapse can be deadly due to loss of tolerance. Also intense feelings of shame and failure that can accompany relapse making it likely that relapse will be concealed as long as possible. Respectful inquiry as a matter of course in primary health care can prevent or identify relapse early. In such cases, therapy with the opioid-antagonist, extended-release injectable naltrexone, or oral naltrexone can be initiated to support recovery prior to relapse to substance use or promptly upon reestablishing abstinence after a relapse; some individuals may require opioid detoxification first. Naltrexone would also be an appropriate consideration for individuals returning to primary care from inpatient rehabilitation or incarceration.