Drugs naloxone

The pure opioid antagonist drugs naloxone,naltrexone, and nalmefene are morphine derivatives with bulkier substituents at the l l17 position. These agents have a relatively high affinity for - opioid binding sites. They have lower... 

There is no drug or magic remedy that can help reverse the effects of barbiturates. For example, with an overdose of a narcotic, such as morphine, the drug naloxone can be given. With barbiturates, only time makes the overdose patient get better. Following overdose, the blood levels will go down and with this, the comatose state and the shallow breathing will lessen. 

Methadone maintenance involves replacing one opiate, say, heroin, with another, methadone. Another pharmacotherapy for heroin use involves blockade of opiate receptors by the use of naltrexone, w hich we discussed in the section on alcohol treatment. Naltrexone or its shorter-acting analogue drug, naloxone, is used most commonly with patients who have been maintained for long periods on methadone and then choose to become drug-free. The naltrexone may help these patients bridge... 

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. 

If the individual has not taken or received an opiate, naloxone has no drug activity. 

This drug is used for complete or partial reversal of narcotic depression, including respiratory depression. Narcotic depression may be due to intentional or accidental overdose (self-administration by an individual), accidental overdose by medical personnel, and drug idiosyncrasy Naloxone also may be used for diagnosis of a suspected acute opioid overdosage. 

These dm may produce withdrawal symptoms in those physically dependent on the narcotics. The patient must not have taken any opiate for the last 7 to 10 days. Naloxone may prevent die action of opioid antidiarrheals, antitussives, and analgesics. This drug is used cautiously during lactation. 

Before the administration of naloxone, the nurse obtains the blood pressure, pulse, and respiratory rate and reviews the record for the drug suspected of causing the overdosage. If there is sufficient time, the nurse also should review the initial health history, allergy history, and current treatment modalities. 

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. 

If naloxone is given by IV infusion, die primary healdi care provider orders die IV fluid and amount, the drug dosage and die infusion rata Giving the drag by IV infusion requires use of a secondary line or IV piggyback. 

When naloxone is used to reverse respiratory depression and the resulting somnolence, the drug is given stow IV push until the respiratory rate begins to increase and somnolence abates Giving a rapid bolus wilt cause withdrawal and return of intense pain. 

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. 

Several narcotic antagonists, including naloxone, naltrexone, L-methadone, and cyclazocine, have been incorporated in lactide homopolymers and lactide/glycolide copolymers. Cyclozocine was incorporated in poly(L-lactide) in the form of films (81,82). Lamination of drug-polymer films with a drug-free film created a reservoir device and eliminated the burst observed with the monolithic films originally tested. 

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 ... 

Delta receptors are relatively selective for two related penta-peptides, methionine enkephalin and leucine enkephalin (met- and leu-enkephalin), which were isolated from porcine brain (Hughes 1975). Both met- and leu-enkephalin inhibit electrically induced contractions of guinea pig ileum, an effect that mimics those effects seen with opioid drugs, and is naloxone reversible. The enkephalins are processed posttranslational ly from proenkephalin, and secreted from central and peripheral neurons and endocrine cells in the adrenal medulla. 

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