Naloxone cannot be abused in any meaningful sense. It produces no high, no euphoria, and no rewarding effects. It works by blocking the same receptors that opioids activate, which means it does the opposite of what a person seeking a drug effect would want. In someone with opioids in their system, naloxone triggers withdrawal. In someone without opioids in their system, it does almost nothing noticeable.
Why Naloxone Has No Recreational Value
Naloxone is a pure opioid receptor antagonist. Rather than switching on the brain’s opioid receptors the way heroin or fentanyl would, it binds to those receptors and blocks them. It has the highest affinity for the mu-opioid receptor, which is the primary target responsible for the euphoria opioids produce. By occupying that receptor without activating it, naloxone prevents any opioid from getting through. There is no mechanism by which this process creates a pleasurable sensation.
When researchers have studied dopamine activity after naloxone administration, they found that it does increase dopamine in the brain, but only during precipitated withdrawal in opioid-dependent individuals. That dopamine surge is not linked to pleasure. In fact, the greater the dopamine increase, the more aversive the experience. Participants who had larger dopamine spikes reported feeling worse, not better. This is the opposite of what happens with drugs of abuse, where dopamine correlates with reward.
What Naloxone Feels Like Without Opioids Present
If a person without opioid dependence takes naloxone, the effects are minimal. In controlled studies of non-dependent volunteers given 1.2 mg of naloxone intravenously, researchers measured six physiological markers that are sensitive to opioid-related changes. Only three showed any response at all: a slight constriction of the pupils, a small drop in core temperature, and a modest decrease in systolic blood pressure. At higher doses in the milligram-per-kilogram range, systolic blood pressure and breathing rate increased slightly. None of these effects are pleasurable or desirable, and they resolve quickly.
The bottom line is that naloxone interacts with the body’s own natural opioid system (endorphins), so it isn’t completely inert. But the effects are subtle, clinically insignificant for most people, and carry zero recreational appeal.
What Happens in Opioid-Dependent Individuals
For someone physically dependent on opioids, naloxone is actively unpleasant. Administering it abruptly strips opioids off the brain’s receptors and triggers what’s called precipitated withdrawal, an intense, fast-onset version of opioid withdrawal. The body responds with a surge of norepinephrine (the stress hormone behind the “fight or flight” response), activation of the hormonal stress axis, and spikes in cortisol. Symptoms come on within minutes and can include nausea, vomiting, muscle cramps, sweating, agitation, and a powerful sense of distress.
This is the core reason naloxone has no abuse potential among the population most likely to encounter it. People who use opioids know that naloxone will make them feel terrible, not high. It is, by design, the pharmacological opposite of a drug of abuse.
Naloxone’s Role in Abuse-Deterrent Medications
Naloxone is deliberately included in certain opioid medications precisely because of its anti-abuse properties. The most well-known example is Suboxone, a combination of buprenorphine (a partial opioid used to treat opioid use disorder) and naloxone. When taken as a dissolving tablet or film under the tongue, the naloxone is poorly absorbed and has little effect. Buprenorphine does the therapeutic work. But if someone dissolves the tablet and injects it, the naloxone enters the bloodstream efficiently and blocks the opioid receptors, triggering withdrawal symptoms. This design makes the medication far less appealing to misuse by injection.
Australian surveillance data from the years after buprenorphine-naloxone entered the market showed that when diversion of the combination product did occur, people primarily used it to self-treat withdrawal symptoms, not to get high. Fewer doses of buprenorphine-naloxone were diverted per 1,000 doses dispensed compared to buprenorphine alone. And when people did divert it, they were more likely to give it away than sell it. The naloxone component was doing its job as a deterrent against injection misuse.
Legal Classification
Naloxone is not a controlled substance under federal law. The DEA’s schedules of controlled substances explicitly exclude naloxone from the category of opium derivatives that fall under Schedule II. It requires no special prescribing authority, and since 2023, the over-the-counter nasal spray Narcan has been available in pharmacies without a prescription. No state treats naloxone as a substance with abuse potential, and many states have passed laws expanding access to make it easier for bystanders to carry and use during overdose emergencies.
Safety at High Doses
While naloxone has no abuse potential, it is worth noting what happens at very high doses, since “can it be abused” sometimes reflects a broader concern about whether it’s dangerous. In a study of 36 stroke patients who received extremely high doses of naloxone (far beyond what any overdose reversal would require), the most common side effects were nausea, slowed heart rate, involuntary muscle jerks, and elevated blood pressure. Seven patients had naloxone discontinued due to side effects, but all recovered once the drug was stopped. No deaths were attributed to naloxone. The drug can cause cardiovascular stress, particularly rapid heart rate and high blood pressure, when it abruptly reverses an opioid overdose, but this is a consequence of sudden withdrawal rather than naloxone toxicity itself.
There is no established lethal dose of naloxone in humans, and no documented pattern of people taking escalating doses to chase an effect. The pharmacology simply does not support it.