Opioid analgesics abuse

Bimbaum HG, White AG, Reynolds JL, et al. Estimated costs of prescription opioid analgesic abuse in the United States in 2001. Clin J Pain 2006 22(8). 

In an epidemiological study of pain and attendant psychopathology in opioid analgesic abusers, 60-70% of all those started on a legitimate prescription of opioids for pain later misused opioids [21... 

Cicero TJ, Lynskey M, Todorov A, Inciardi JA, Surratt HL. Co-morbid pain and psychopathology in males and females admitted to treatment for opioid analgesic abuse. Pain 2008 139(1) 127-35. 

Which of the following is associated with abuse of opioid analgesics ... 

Modest abuse potential with possible medical value in U.S. Mild opioid analgesics, some cough syrups, etc. 

Joranson DE, Ryan KM, Gilson AM, Dahl JL. (2000). Trends in medical use and abuse of opioid analgesics. JAMA. 283(13) 1710-14. 

These differences in the behavioural properties of the opioid receptor sub-types are of considerable interest because the clinical use of currently marketed opioid analgesic drugs is limited by their undesirable side-effects, which include respiratory depression, constipation and an abuse or dependence liability. These side-effects have been associated with mu receptor ac-... 

Pentazocine (Talwin) (see also page 252) Street Names Crackers, poor man s h oin, T s and R s> Ts and Rits (all refer to combinations w/ Ritalin) (brands Talwin, Talwin Nx [CIV]) Use Medically used as opioid analgesic euphoria similar to heroin when mixed w/antihistamines combined w/ methylphenidate (Ritalin) is new abuse combination Actions Agonist-antagonist narcotic naloxone, a narcotic antagonist added to Talwin (Talwin NX) has reduced incidence of abuse Effects Euphoria, hallucinations, skin necrosis w/ illicit injection route... 

Codeine, one of the principal alkaloids of opium, has an analgesic efficacy much lower than other opioids, due to an extremely low affinity for opioid receptors. It is approximately one-sixth as potent as morphine. It has a low abuse potential. In contrast to other opioids, with the exception of oxycodone, codeine is relatively more effective when administered orally than parenterally. This is due to methylation at the C3 site on the phenyl ring (Figure 7.3), which may protect it from conjugating enzymes. It is used in the management of mild-to-moderate pain, often in combination with non-opioid analgesics, such as aspirin or paracetamol. It is valuable as an antitussive and for the treatment of diarrhoea. Side effects are uncommon and respiratory depression, even with large doses, is seldom a problem. 

The euphoria, indifference to stimuli, and sedation usually caused by the opioid analgesics, especially when injected intravenously, tend to promote their compulsive use. In addition, the addict experiences abdominal effects that have been likened to an intense sexual orgasm. These factors constitute the primary reasons for opioid abuse liability and are strongly reinforced by the development of physical dependence. This disorder has been linked to dysregulation of brain regions mediating reward and stress (see Chapter 32). 

Joranson, David E., et al. Trends in Medical Use and Abuse of Opioid Analgesics. The Journal of the American Medical Association 282 (April 5, 2000) 1710-4. 

Obviously, the risk of causing dependence is an important consideration in the therapeutic use of these drugs. Despite that risk, under no circumstances should adequate pain relief ever be withheld simply because an opioid exhibits potential for abuse or because legislative controls complicate the process of prescribing narcotics. Furthermore, certain principles can be observed by the clinician to minimize problems presented by tolerance and dependence when using opioid analgesics ... 

Diamorphine Diamorphine is relatively unstable in aqueous solutions, and minimum decomposition was observed at pH 4. Preparations should be used within 4 weeks when kept at room temperature, but degradation products also have analgesic activity.45,46 Diamorphine is used in the management of opioid dependence this is also a drug of abuse and the overdose is fatal47,48 Interactions are similar to those of opioid analgesics. Withdrawal symptoms of opioid dependence can be treated with diamorphine and methadone.49... 

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