What does oxycodone do to the body?

Addictive drugs directly activate the brain’s reward pathway, a system involved in behavior reinforcement and memory production.

Activation of the reward system can be so intense that normal activities, like eating and sleeping, may be forgotten and/or neglected. Drugs of abuse characteristically enhance dopamine signaling in an area of the reward pathway called the nucleus accumbens (NA.) The NA is sometimes called the “pleasure center” of the brain. It releases dopamine when the brain senses a rewarding stimulus, such as a narcotic, and this rush of chemicals reinforces the behavior that caused the sensation, for example ingesting a pill. Thus, the cycle of pleasure seeking begins and an addiction is cultivated.


Brain scan


Different drugs affect dopamine by different mechanisms of action. Oxycodone works by binding to opioid receptors, mimicking natural feel-good chemicals and inhibiting brain cells that inhibit dopamine-secreting cells, which ultimately enhances dopamine release as well. It creates long-term changes in the NA, which affect the way the NA responds to another chemical called glutamate. This disturbance contributes to drug cravings by causing the user to remember past drug use vividly.

Physical signs of oxycodone addiction

Mental Signs and Symptoms

  • Drowsiness
  • Reduced pain
  • Lightheadedness
  • Headache
  • Confusion
  • Seizures

Internal Signs and Symptoms

  • Constipation
  • Nausea/vomiting
  • Hoarseness
  • Muscle relaxation
  • Weakness
  • Dry mouth
  • Low blood pressure
  • Postural hypotension
  • Respiratory depression
  • Difficulty swallowing
  • Irregular heartbeat
  • Chest pain

External Signs and Symptoms

  • Itching
  • Hives, itching, or rash
  • Sweating
  • Swelling
  • Flushing
  • Constricted pupils

Behavioral signs of oxycodone addiction

  • Euphoria
  • Extreme relaxation
  • Sedation
  • Reduced anxiety
  • Mood swings

What are the effects of oxycodone abuse and addiction?

Using the drug incorrectly can lead to "opioid-induced hyperalgesia," meaning that once non-painful stimuli will suddenly be detected as painful by the altered brain. In fact, the pain intensity often becomes stronger than initially reported.

Additionally, using the drug for long periods of time can lead to tolerance, meaning that you have to take more and more of the drug just to achieve the original result.

Recreational use of oxycodone is extremely dangerous, as improper methods of ingestion often accelerate drug absorption, which can greatly increase the risk of overdose. Oxycodone abuse has also been associated with kidney and liver failure, especially when used in combination with acetaminophen and/or alcohol.

What causes Oxycodone addiction?

Oxycodone is an opiate analgesic. This means that it causes pain relief by binding to certain areas in the nervous system and GI tract called “opioid receptors” and changing the way your body and brain respond to pain. Oxycodone and other opioids induce an intensely pleasurable euphoric feeling, so users are at a high risk of both psychological and physiological addiction.

Can anyone become addicted to oxycodone?

No one is immune to addiction; even patients who take oxycodone (or other prescribed opioids) for legitimate medical reasons can become addicted. Medical necessity does not “protect” against addiction, yet this misconception is causing some physicians to overconfidently write opioid prescriptions without monitoring for addictive behavior. Medical professionals must always be on the lookout for warning signs and be ready to intervene as needed; even patients who take the drugs exactly as prescribed can become addicted.

However, the reality is that legal opioids are highly effective for treating pain, and only a small percentage of patients prescribed opioids become addicted, even among those with highly addictive tendencies. It should be noted, though, that the risk of addiction does slightly increase for individuals who take opioids for a long time (more than three months) or at high doses (over 100 morphine milligram equivalents (MMEs)). The risk also increases for adolescents, and individuals with depression and/or substance use disorder(s). Additionally, genetics account for 35-40% of the risk associated with addiction.

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