Injectable methadone

In the course of clinical treatment with methadone, certain situations relating to adverse effects are characteristic. Nausea is a general opiate effect, but complaints most frequently relate to the methadone mixture. This preparation does have a syrupy consistency, but the problem for clinicians is that the alternatives - sugar-free mixture or methadone tablets - are both more injectable, and therefore requests or implied requirements for these are often manipulative. So are requests for the antiemetic cyclizine tablets, which are crushed and injected by drug misusers along with injected methadone. As indicated in Chapter 4, thankfully these particular claims have become less common now that guidelines are much more discouraging of any use of methadone tablets. 

Metrebian N, Shanahan W, Stimson GV et al. (2001). Prescribing drug of choice to opiate dependent drug users a comparison of clients receiving heroin with those receiving injectable methadone at a West London drug clinic. Drug and Alcohol Review, 20, 267-76... 

Methadone Injection (Methadone hydrochloride). Rosemont Pharmaceuticals Ltd UK Summary of product characteristics, January 2005. 

In an open, randomized trial, heroin addicts in treatment were randomized to supervised injectable heroin (n = 43), supervised injectable methadone (n = 42) or... 

Strang J, Metrebian N, Lintzeris N, Potts L, Carnwath T, Mayet S, Williams H, Zador D, Evers R, Groshkova T, Charles V, Martin A, Forzisi L. Supervised injectable heroin or injectable methadone versus optimised oral methadone as treatment for chronic heroin addicts in England after persistent failure in orthodox treatment (RIOTT) a randomised trial. Lancet 2010 375(9729) 1885-95. 

The approval of buprenorphine for the office-based treatment of opioid dependence represents a major departure from the earlier methadone clinic system. Physicians with addiction specialist credentials or those who have completed 8 hours of approved training can become qualified to treat up to 30 patients in their private offices. Stable patients may be given prescriptions for up to a month of medication. The combination buprenorphine/naloxone tablet is expected to have minimal risk for diversion. When taken subhnguaUy, as prescribed, naloxone has minimal biologic activity and does not interfere with the buprenorphine dose. However, if an attempt is made to inject the drug, the addict will experience the full antagonist effect of the naloxone. 

Dopaminergic system, LSD-induced alterations of, 159-160 Dorsal raphe nucleus (DRN) injection of LSD, morphine, and methadone into, comparison of discriminate stimulus properties of, 84, 85... 

FIG. 2. Comparison of the discriminative stimulus properties of LSD, morphine, and methadone when injected into the DRN of the rat. Rats were trained to discriminate LSD (120 ng/kg s.c.), cannulae implanted, and generalization from peripheral to central administration determined over a variety of doses of each drug. (Redrawn from the research of Rosecrans and Glennon, ref. 59.) A, I.C. saline, , I.C. morphine in morphine trained rats, O, I.C. saline, , I.C. LSD in LSD trained rats, , I.C. saline, , I.C. methadone in methadone trained rats. 

FIGURE 4 Chiral CE ESI/MS analysis of five amphetamine derivatives and two pharmaceutical compounds. Total ion current (TIC) and extracted ion currents (XIC) of amphetamine (A), methamphetamine (MA), methylenedioxyamphetamine (MDA), methylenedioxymethamphetamine (MDMA), and methylenedioxyethylamphetamine (MDEA), and tramadol (TMD) and methadone (MTD) in plasma after LLE with electrokinetic injection. 

Methadone, used as an analgesic, may be dispensed in any licensed pharmacy. Methadone dispersible tablets are for oral administration only. This preparation contains insoluble excipients and therefore must not be injected. It is recommended that methadone dispersible tablets, if dispensed, be packaged in child-resistant containers and kept out of the reach of children to prevent accidental ingestion. 

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