Naloxone effect

Janowsky DS, Judd L, Huey L, et al. Naloxone effects on manic symptoms and growth-hormone levels. Lancet 1978 i 320. 

Zipeprol [34758-83-3] (58) is another European antitussive with a wide range of pharmacological effects, including antispasmodic, antihistaminic, and local anesthetic activities (85,86). It has been reported that zipeprol has been abused in Italy because high doses cause hallucinations (87). Spontaneous withdrawal symptoms similar to those of opiates have been observed withdrawal symptoms can also be precipitated by naloxone. Zipeprol can be... 

Opiate overdose is a medical emergency that can result in respiratory and CNS depression. The opioid receptor antagonist naloxone immediately reverses cardiorespiratory depression. However, repeated naloxone administration is required, since the effects of naloxone last for 30 min, while opioid agonists can remain at potentially lethal blood levels for several hours. 

The pharmacological and/or adverse effects of a drug can be reversed by co-administration of drugs which compete for the same receptor. For example, an opioid receptor antagonist naloxone is used to reverse the effects of opiates. Drugs acting at the same site with opposite effects also can affect each other, e.g. the reduction in the anticoagulant effect of warfarin by vitamin K. 

The risk of respiratory depression is a concern for many nurses administering a narcotic and may cause some nurses to hesitate to administer the drug. However, respiratory depression rarely occurs in patients using a narcotic for pain. In fact, these patients usually develop tolerance to the respiratory depressant effects of the drug very quickly. Naloxone (see Chap. 20) can be administered to reverse the narcotic effects if absolutely necessary. 

Naloxone should be administered with great caution and only when necessary in patients receiving a narcotic for severe pain. Naloxone removes all of the pain-relieving effects of the narcotic and may lead to withdrawal symptoms or the return of pain. 

Administration of naloxone prevents or reverses the effects of the opiates. The exact mechanism of action is not fully understood, but it is believed that naloxone reverses opioid effects by competing for opiate receptor sites (see Chap. 19). If the individual has taken or received an opiate, the effects of the opiate are reversed. 

Naltrexone completely blocks the effects of IV opiates, as well as drugp with agonist-antagonist actions (butorphanol, nalbuphine, and pentazocine). The mechanism of action appears to be the same as that for naloxone... 

As part of the ongoing assessment during the administration of naloxone, the nurse monitors the blood pressure, pulse, and respiratory rate at frequent intervals, usually every 5 minutes, until the patient responds. After the patient has shown response to the drug, the nurse monitors vital signs every 5 to 15 minutes. The nurse should notify tlie primary healdi care provider if any adverse drug reactions occur because additional medical treatment may be needed. The nurse monitors die respiratory rate, rhydun, and depdi pulse blood pressure and level of consciousness until the effects of die narcotics wear off. 

The effects of some narcotics may last longer than the effects of naloxone. A repeat dose of naloxone may be ordered by the primary health care provider if results obtained from the initial dose are unsatisfactory. The duration of close patient observation depends on the patient s response to the administration of the narcotic antagonist. 

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. 

Naltrexone (Trexan) is the only opioid antagonist currently in use for treatment of addiction. Naloxone is used to treat opioid overdose and to test for opioid addiction but has a short half-life and is relatively ineffective orally cyclazocine s dysphoric side effects make it unacceptable (Resnick et al. 1980). Patients who are likely to continue to use naltrexone and to benefit from treatment are those who have established careers (e.g., health professionals) and family support and are well motivated. Up to 70% of such clients are abstinent at 1-year follow-up (Washton et al. 1984). Programs that utili2e additional rehabilitative services have better results than those that provide minimal services. Successful treatment is also associated with taking naltrexone... 

Heishman SJ, Stitzer ML, Bigelow GE, et al Acute opioid physical dependence in postaddict humans naloxone dose effects after brief morphine exposure. J Pharmacol Exp Ther 248 127-134, 1989... 

The opioid antagonists naloxone and naltrexone bind to aU three opioid receptors, p, K, and 8. These compounds are antagonists due to their inability to elicit downstream effects of these receptors once bound (Sarton et al. 2008 Yaksh and Rudy 1977). Interestingly, both antagonists have a high binding affinity for MORs. Naloxone is used to reverse the effects of an acute opioid overdose because of its rapid onset of action. Naltrexone elicits similar actions, but has a longer onset and duration of action and hence, is used for the maintenance of treatment for opioid addicts. 

Most of the work has been based on opioids since it is the easiest system to manipulate as administration of the antagonist, naloxone, precipitates withdrawal. Flere, the idea that physical dependence results from opposing changes in the neuronal systems depressed by the drug of dependence is borne out by consideration of the acute effects of an opioid and the withdrawal symptoms. They are mirror images of each other ... 

Griffiths, RR. Wurster, R.M. and Brady, J.V. Discrete-trial choiee proeedure Effects of naloxone and methadone on choice between food and heroin. Pharmacol Rev 27 357-365. 1975. 

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