Meperidine abuse

Patients who are acutely intoxicated with an opioid usually present with miosis, euphoria, slow breathing and slow heart rate, low blood pressure, and constipation. Seizures may occur with certain agents such as meperidine (Demerol ). It is critically important to monitor patients carefully to avoid cardiac/ respiratory depression and death from an excessive dose of opioids. One strategy is to reverse the intoxication by utilizing naloxone (Narcan ) 0.4 to 2 mg IV every 2 to 3 minutes up to 10 mg. Alternatively, the IM/SC route may be used if IV access is not available. Because naloxone is shorter-acting than most abused opioids, it may need to be readministered at periodic intervals otherwise the patient could lapse into cardiopulmonary arrest after a symptom-free interval of reversed... 

Schedule II—The drug or other substance has (1) a high potential for abuse, (2) a currently accepted medical use in treatment in the United States or a currently accepted medical use with severe restrictions, and (3) abuse of the drug or other substances may lead to severe psychological or physical dependence. Examples cocaine, PCP, morphine, fentanyl and meperidine, codeine, amphetamine and methamphetamine, Ritalin . 

Diphenoxylate is a synthetic meperidine analog with little or no analgesic activity. However in high doses it shows opioid activity such as euphoria and a morphine-like physical dependence after chronic administration. Its insolubility however, in aqueous solution prevents parenteral abuse. Nevertheless, diphenoxylate has in most countries been replaced by loperamide. 

Geriatric Considerations - Summary Diphenoxylate is an analog of meperidine and can cause opiate adverse effects. When discontinued, physical dependence and withdrawal symptoms can occur. Adverse GI effects such as constipation, nausea/vomit-ing, and abdominal pain may result from normal doses. Afropine is added to discourage abuse but can cause anticholinergic adverse effects in the older adult. The benefits of f his drug combination for older adulfs are limifed by fhe risk of adverse effects. 

Opioids (opium, morphine, heroin, meperidine, methadone, etc) are common drugs of abuse (see Chapters 31 and 32), and overdose is a common result of using the poorly standardized preparations sold on the street. See Chapter 31 for a detailed discussion of opioid overdose and its treatment. 

Numerous studies have reported that performance on the DSST was impaired by various opioids, including morphine (2.5 to 10 mg),185,198 fentanyl (1 to 2.5 ng/ml),182 pentazocine (30 mg),184 butorphanol (0.5 to 2 mg),186 dezocine (2.5 to 10 mg),187 propofol (22 to 70 mg),193,199 nalbuphine (2.5 to 10 mg, IV),189 and the combination of fentanyl (50 pg) plus propofol (35 mg).194 In contrast, meperidine was found to have no effect on the DSST.192 Because the DSST is a timed test, it would appear that opioids slow speeded responses in a fairly consistent manner in opioid-naive subjects. However, in opioid abusers or opioid-dependent persons, Preston and colleagues have reported no effect on DSST performance of several opioids, including morphine (7.5 to 30 mg, IM),200 hydro-morphone (0.125 to 3 mg, IM),201 buprenorphine (0.5 to 8 mg, IM),202 pentazocine (7.5 to 120 mg, IM),203 butorphanol (0.375 to 1.5 mg, IV),204 and nalbuphine (3 to 24 mg, IM).205... 

Opiate preparations, usually given as paregoric, are effective and fast acting antidiarrheal agents. These agents are also useful postoperatively to produce solid stool following an ileostomy or colostomy. A meperidine derivative, diphenoxylate, is usually dispensed with atropine and sold as Lomotil. The atropine is added to discourage the abuse of diphenoxylate by narcotic addicts who are tolerant to massive doses of narcotic but not to the CNS stimulant effects of atropine. 

Each year, the National Household Survey on Drug Abuse (NHSDA)—the United States Department of Health and Human Services—collects statistical data on five drug groups marijuana and hashish psychotherapeutic drugs cocaine and crack hallucinogens and inhalants. Psychotherapeutic drugs include stimulants, sedatives, tranquilizers, and pain relievers. Meperidine and other opioids constitute the majority of the pain relievers in that group. 

Evidence indicates that proper meperidine prescription for legitimate medical concerns does not greatly increase the risk of addiction and abuse. Those in the medical community agree that more education is needed by both doctors and patients to help prevent the potential for abuse and addiction, so that patients truly in need are not denied access to meperidine based on misperceptions and fear. The benefits for individuals and society are great when pain is treated safely and effectively. 

The opioid drugs are responsible for more reported cases of renal damage than any other class of abused drug. While opioids include morphine, codeine, methadone, meperidine, and other agents, most cases of renal damage are related to heroin abuse. Heroin is derived from the acetylation of morphine at two-sites and is rapidly absorbed from all mucous membranes and the lungs. 

Heroin was first synthesized from morphine over a century ago. Since then, it has become one of the most abused substances. Research into why it produces such powerful effects has led to the discovery of specific opiate receptors and endogenous opioids (enkephalins and endorphins). These peptides appear to be neurotransmitters involved with the sensation of pain and pleasure. A number of opiates and synthetic opioids are available and can lead to dependency, including morphine, heroin, propoxyphene (Darvon), methadone, meperidine (Demerol), pentazocine (Talwin), hy-dromorphone (Dilaudid), oxycodone (Percodan), and hydrocodone (Vicodin, Damason-P), and codeine. 

Prescription regulations for most CNS drugs are based on their abuse liability. The potent opioid analgesics (e.g., morphine, methadone, meperidine, fentanyl) are judged to have the highest potential for abuse, along with CNS stimulants (e.g., amphetamine, cocaine) and short-acting barbiturate (e g., secobarbital). No refills or telephone prescriptions are permissible. 

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