Transcript OPIOIDS
OPIOIDS I. Where do they come from? – poppy plant: from middle east and Asia – dried sap from plant is opium; cultivated annually BUT plant produces drug within only 10 day window over 87% of world’s opium comes from Afghanistan (2005 U.N. report) – major active ingredient in opium: morphine / synthesized in 1803 / named after the Greek god of dreams Morpheus / morphine altered in late 1800s into heroin a “heroic” TX (3-10x as strong as morphine) / Fentanyl OPIOIDS Other names they go by? - Oxycodone - Codeine: Lean; Purple stuff (cough syrup with sprite and jolly ranchers) - others? ______________ OPIOIDS II. Medical Uses – As pain reliever (morphine, demerol, codeine, lortab, lorcet, percodan, percocet, vicodin, oxycontin) – with chronic pain or terminal patients – in some cough suppressants – treatment of diarrhea, which is dehydrating OPIOIDS III. Prevalence Heroin compared to non-medical use of rx Pain meds: Lifetime 2004: H: 1.3% P: 13.2% Past Year Current 0.2% 4.7% 0.1% 1.8% - new heroin users may smoke, sniff or snort it rather than inject……why ? OPIOIDS IV. Mechanisms of action • opiates trigger our own brain chemicals, the endorphins (short for “endogenous morphine”) to relieve pain • naloxone ____________ effects of opiates by blocking opiate receptor sites OPIOIDS V. Effects • produces short-lived euphoria, profound relaxation, body warmth (lowers body temp) • tolerance develops rapidly so increasing doses is very common • drug taking becomes a chore to avoid withdrawal SX - illustrates ? reinforcement Rats: heroin tolerant Received injection of heroin 15 mg/kg in familiar environment Overdose rate: % Rats: heroin tolerant Received injection of heroin 15 mg/kg in unfamiliar environment Overdose rate: % Received injection of heroin 15 mg/kg for first time Overdose rate: % Control rats: No heroin tolerance A diagram of Siegel’s rat experiment OPIOID WITHDRAWAL • Stoppage (or reduction] in opioid use that has been heavy and prolonged (several weeks +) • OR administration of opioid antagonist after period of use • Symptoms include: (need at least 3 for DSM criteria) – – – – – – dysphoric mood diarrhea muscle aches insomnia nausea or vomiting runny eyes or nose - yawning - fever - dilation of pupils, piloerection or sweating OPIOIDS VI. Treatment - methadone TX: peak concentration occurs 2-4 hours after taken, in contrast to effects of other opiates which kick in right away like a hammerblow; metabolites of methadone are inactive, unlike other narcotics - blood levels of methadone, when given orally, is below ED level in tolerant patients, and is safely above the threshold for withdrawal...so, methadone combines safety and long action - LAAM, naltrexone, buprenorphine - TCs OPIOIDS - Controversy • Needle exchange programs to prevent HIV: are you pro/con? • Should heroin be given to terminal patients? Do terminal patients have right to die with drugs? • Should non-terminal pain patients be freely medicated with morphine or even stronger painkillers? Prescription Opioid Abuse Historical Aspects 1990 - Current • Through the efforts of pain control advocates, organized medicine, scientific journals, & malpractice suits, prescribing opiates for pain became more common during the last decade of the 20th Century • Opioid therapy became accepted (although often inadequately) for treating acute pain, pain due to cancer, & pain caused by a terminal disease • Still disputed is the use of opioids for chronic pain not associated with terminal disease Evolving Landscape of Drugs of Abuse Farming Pharming 13 Potential subpopulations of prescription Opioid Abusers Persons who abuse or are dependent on only prescription opioids Abusers of other opioids, e.g., heroin, when they cannot get their drug of choice Polydrug abusers Pain patients who develop abuse or dependence problems on these drugs in the course of legitimate medical treatment Why Has the Abuse of Prescription Drugs Been Increasing? • Increasing numbers of prescriptions • Others? As Prescriptions Increase, ER Reports Have Increased at the Same or Faster Rate Number of Prescriptions (in 1000s) 24000 80000 70000 Hydrocodone . 18000 prescriptions emergency 60000 50000 12000 40000 30000 Oxycodone prescriptions emergency 20000 6000 10000 0 1994 1995 1996 1997 1998 1999 2000 0 2001 Source: IMS Health for Prescriptions and SAMHSA (DAWN) for Emergency Department Mentions