Opioids are powerful pain killers that are highly addictive. They can be divided into 3 classes:
- Naturally occurring opioids: These occur naturally & include morphine, narcotine, codeine, thebaine, papaverine and narceine.
- Semi-synthetic opioids: These include heroin, oxycodone, oxymorphone, and hydrocodone.
- Synthetic opioids: These include buprenorphine, methadone, fentanyl, alfentanil, levorphanol, meperidine, and propoxyphene.
Opioids can be taken orally, snorted intranasally & injected intravenously or subcutaneously. These are addictive because of their euphoric property. Other symptoms include a feeling of warmth, heaviness of the extremities, dry mouth, itchy face & facial flushing. It can also induce dysphoria, nausea & vomiting.
People affected with opioid use disorders frequently fluctuate between the physical states of intoxication & withdrawal.
Aetiology of Opioid Use Disorder:
- Genetic Factors (About 50-60%)
- Drug availability
- Social acceptability
- Family history of substance dependence
- Parental conflicts
- Peer pressure
Opioid withdrawal develops after the cessation of or reduction in opioid use that have been heavy & prolonged.
- Severe muscle cramps & Body-ache.
- Abdominal cramps
- Piloerection or goose flesh
- Pupillary dilation
- Temperature dysregulation
- Nausea/ vomiting.
At anytime during the abstinence syndrome, a single injection of morphine or heroin eliminates all the symptoms of opioid withdrawal.
Comorbidity of Opioid Use Disorder:
(I) Psychiatric Illness:
About 70% of men & 75% of women with opioid use disorder have an additional psychiatric disorder. Most common comorbid psychiatric disorders are:
- Mood Disorders
- Antisocial Personality Disorders
- Anxiety Disorders
- Alcohol Use Disorders
(II) Physical Illness:
Major health consequences of opioid use disorders include an increased risk of blood borne infections such as HIV, HCV & HBV.