Opioid Addiction Treatment and Methadone Use

Administration (FDA) for the treatment of opioid addiction. Treatment is initiated with buprenorphine alone administered sublingually, followed by maintenance therapy with a combination of buprenorphine and naloxone (Suboxone) to minimize abuse potential. The partial agonist properties of buprenorphine limit its usefulness for the treatment of addicts who require high maintenance doses of opioids. However, conversion to maintenance treatment with higher doses of methadone, a full agonist, is possible. 

Two opioids are used in the treatment and management of opiate dependence levomethadyl and methadone. Levomethadyl is given in an opiate dependency clinic to maintain control over the delivery of the drug. Because of its potential for serious and life-threatening proarrhythmic effects, levomethadyl is reserved for use in the treatment of addicted patients who have no response to other treatments. Levomethadyl is not taken daily the drug is administered three times a week (Monday/Wednesday/Thursday or Tuesday/Thursday/ Saturday). Daily use of the usual dose will cause serious overdose. 

A 2.5-yeat follow-up study of opioid addicts in methadone maintenance treatment found that prevalence of cocaine use only shghtly declined and that... 

Anxiety disorders are common in the population of opioid-addicted individuals however, treatment studies are lacking. It is uncertain whether the frequency of anxiety disorders contributes to high rates of illicit use of benzodiazepines, which is common in methadone maintenance programs (Ross and Darke 2000). Increased toxicity has been observed when benzodiazepines are co-administered with some opioids (Borron et al. 2002 Caplehorn and Drummer 2002). Although there is an interesting report of clonazepam maintenance treatment for methadone maintenance patients who abuse benzodiazepines, further studies are needed (Bleich et al. 2002). Unfortunately, buspirone, which has low abuse liability, was not effective in an anxiety treatment study in opioid-dependent subjects (McRae et al. 2004). Current clinical practice is to prescribe SSRIs or other antidepressants that have antianxiety actions for these patients. Carefully controlled benzodiazepine prescribing is advocated by some practitioners. 

A dramatically different pattern is found in surveys of drug abuse treatment facilities. Substance abuse treatment centers have reported that more than 20% of patients use benzodiazepines weekly or more frequently, with 30%— 90% of opioid abusers reporting illicit use (Iguchi et al. 1993 Stitzer et al 1981). Methadone clinics reported that high proportions ofurine samples are positive for benzodiazepines (Darke et al. 2003 Dinwiddle et al. 1996 Ross and Darke 2000 Seivewright 2001 Strain et al. 1991 Williams et al. 1996). The reasons for the high rates of benzodiazepine use in opioid addicts include self-medication of insomnia, anxiety, and withdrawal symptoms, as well as attempts to boost the euphoric effects of opioids. 

Methadone (Dolophine) has an analgesic profile and potency similar to that of morphine but a longer duration of action and better oral bioavaUabUity. The kinetic properties of methadone and its derivative, LAAM, have been shown to be useful in the treatment of opioid addiction, as discussed in Chapter 35. 

The dangers of dependency and addiction clearly preclude the use of such compounds as morphine, meperidine, and methadone as treatment for diarrhea. Antidiarrheal specificity therefore is of paramount importance in choosing among the synthetic opioids and their analogues (e.g., diphenoxylate and loperamide). 

Darke S (1998). The effectiveness of methadone maintenance treatment. 3 Moderators of treatment outcome. In Ward J, Mattick RP, Hall W (eds.) Methadone Maintenance Treatment and Other Opioid Replacement Therapies. London Harwood, pp. 75-90 Darke S, Hall W, Wodak A, Heather N Ward J (1992a). Development and validation of a multi-dimensional instrument for assessing outcome of treatment among opiate users the Opiate Treatment Index. British Journal of Addiction, 87, 733-42 Darke S, Hall W, Ross MW Wodak A (1992b). Benzodiazepine use and HIV risk-taking... 

Methadone is widely used in the treatment of opioid abuse. Tolerance and physical dependence develop more slowly with methadone than with morphine. The withdrawal signs and symptoms occurring after abrupt discontinuance of methadone are milder, although more prolonged, than those of morphine. These properties make methadone a useful drug for detoxification and for maintenance of the chronic relapsing heroin addict. 

Analgesic efficacy and clinical use Levomethadone like racemic methadone is a potent and long-acting opioid analgesic and can be used for the treatment of moderate to severe pain (Jamison, 2000 Davis and Walsh, 2001). It has an action profile similar to morphine and has significant antitussive properties, for which it is used in terminal lung cancer. The long duration of action makes the compound suitable for substitution treatment of opioid addiction (Joseph et al., 2000 Pallenbach, 2002). For practical and economic reasons the racemate instead of the levo-enantiomer is used in addicts. 

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