Opioid Use Disorder (OUD)

How opioid use disorder develops

Opioids bind to receptors in the brain that relieve pain and trigger a release of dopamine, creating euphoria. With repeated use:

• tolerance develops, so more is needed for the same effect
• physical dependence develops, so stopping causes withdrawal
• the brain's reward and stress systems change, producing strong cravings and making it hard to stop despite consequences

Physical dependence alone is not OUD. People taking opioids for pain as prescribed can be dependent without having OUD. OUD involves loss of control and continued use despite harm.

Signs and diagnosis

DSM-5 lists 11 criteria over a 12-month period. Having 2 to 3 indicates mild OUD, 4 to 5 moderate, and 6 or more severe:

1. taking more or for longer than intended
2. wanting or trying to cut down without success
3. spending a lot of time obtaining, using or recovering
4. cravings
5. failing to meet obligations at work, school or home
6. continuing despite relationship problems
7. giving up important activities
8. using in physically dangerous situations
9. continuing despite physical or mental health problems
10. tolerance
11. withdrawal

(Tolerance and withdrawal do not count when opioids are taken as prescribed under medical supervision.)

Other signs others may notice: drowsiness, small pupils, mood swings, isolation, money problems, doctor shopping, and missing medicines.

Opioid withdrawal

Withdrawal usually starts 6 to 12 hours after the last dose of short-acting opioids, peaks at 1 to 3 days, and lasts about a week. Timing after fentanyl can be less predictable, and methadone withdrawal starts later and lasts longer.

• anxiety, restlessness and insomnia
• muscle aches and yawning
• runny nose and watery eyes
• sweating, chills and goosebumps
• dilated pupils
• nausea, vomiting, stomach cramps and diarrhea
• strong cravings

Withdrawal is rarely life-threatening in itself, but dehydration can be dangerous, and loss of tolerance afterward greatly raises the risk of fatal overdose if use resumes.

Risk factors

• long-term or high-dose opioid prescriptions
• personal or family history of substance use disorder
• mental health conditions such as depression, anxiety and PTSD
• chronic pain
• trauma, adverse childhood experiences and social stress
• younger age at first use

Treatment

Medicines for opioid use disorder (MOUD)

MOUD reduces overdose deaths, infections, illegal drug use and criminal justice involvement. Treatment is often long term; stopping too early increases relapse and overdose risk. Any clinician with a DEA registration can now prescribe buprenorphine for OUD.

Withdrawal management

Medically supported withdrawal uses buprenorphine, methadone or non-opioid medicines such as lofexidine or clonidine. Detox alone, without ongoing MOUD, has high relapse rates and should lead into continued treatment.

Psychosocial support

• counseling and cognitive behavioral therapy
• contingency management
• peer recovery support and mutual-help groups
• treatment of co-occurring mental health conditions
• help with housing, employment and legal issues

Treatment in pregnancy

Buprenorphine or methadone is recommended during pregnancy rather than withdrawal, because it protects both parent and baby. Babies may have temporary withdrawal symptoms after birth, which are treatable.

Overdose: recognition and response

Signs of opioid overdose:

• unresponsive or very hard to wake
• slow, shallow or stopped breathing; snoring or gurgling
• blue, gray or pale lips and fingertips
• pinpoint pupils

What to do:

1. Call 911 or your local emergency number.
2. Give naloxone (nasal spray in one nostril). Give a second dose after 2 to 3 minutes if there is no response.
3. Give rescue breaths or CPR if trained, or place in the recovery position.
4. Stay until help arrives; naloxone can wear off before the opioid does.

Most US states have Good Samaritan laws that offer some legal protection to people who call for help during an overdose.

Reducing risk

• carry naloxone and make sure people around you know where it is
• never use alone, or use a never-use-alone hotline
• use fentanyl test strips
• avoid mixing opioids with alcohol, benzodiazepines or xylazine-containing drugs
• start low after any break in use
• use sterile needles and syringe services programs

Complications

• overdose and death
• infections: hepatitis C, HIV, skin abscesses and endocarditis
• constipation and hormonal effects
• depression and suicide risk
• legal, financial and relationship harm

Frequently asked questions

What are the signs of opioid use disorder?

Signs include taking more opioids than intended, being unable to cut down, strong cravings, spending a lot of time getting or using opioids, neglecting responsibilities, needing more for the same effect, and withdrawal when stopping. A clinician uses DSM-5 criteria to diagnose it.

What is the best treatment for opioid addiction?

Medicines for opioid use disorder (buprenorphine, methadone or extended-release naltrexone), combined with counseling and support, are the most effective treatment. Buprenorphine and methadone reduce the risk of overdose death by about half.

How long does opioid withdrawal last?

For short-acting opioids like heroin or oxycodone, withdrawal typically starts within 6 to 12 hours, peaks in 1 to 3 days and settles within about a week. Methadone withdrawal lasts longer. Cravings and sleep problems can persist for weeks to months.

How does naloxone work?

Naloxone knocks opioids off their receptors in the brain, quickly reversing breathing depression. It works within 2 to 3 minutes as a nasal spray and is available over the counter. More than one dose may be needed with fentanyl, and emergency help is still required.

Is opioid use disorder a disease?

Yes. Opioid use disorder is recognized as a chronic medical condition involving changes in brain function. Like diabetes or heart disease, it can be managed with ongoing treatment, and recovery is possible.