Respiratory depression, with narcotics

The most serious side effect of the opioids is respiratory depression.The narcotic agonists suppress the brainstem respiratory centers and thus alter tidal volume, respiratory rate, rhythmicity, and responsiveness to CO2. When used in equianalgesic doses, the opioids, with the exception of pentazocine, produce similar degrees of respiratory depression.Therapeutic doses of opioid analgesics are unlikely to produce significant respiratory depression in most healthy patients.The opioids must be used with caution, however, in patients with preexisting pulmonary disease, especially patients with airway compromise such as chronic obstructive pulmonary disease. 

Do not take alcohol or CNS depressants with narcotic analgesics. Respiratory depression can occur. Avoid constipating foods such as eggs and cheese. 

Cohen SE, Rolhblatt AJ, Albright GA. Early respiratory depression with epidural narcotic and intravenous droperidol. Anes esiology (1983) 59,559-60. 

This type of pain management is used for postoperative pain, labor pain, and cancer pain. The most serious adverse reaction associated with the administration of narcotics by the epidural route is respiratory depression. The patient may also experience sedation, confusion, nausea, pruritus, or urinary retention. Fentanyl is increasingly used as an alternative to morphine sulfate because patients experience fewer adverse reactions. 

Fhtients receiving long-term opioid therapy rarely have problems with respiratory depression. In instances where respiratory depression occurs, administration of a narcotic antagonist (see Chap. 20) may be ordered by die primary health care provider if die respiratory rate continues to fall. 

Drug dependence Administer cautiously to people who are known or suspected to be physically dependent on opioids, including newborns of mothers with narcotic dependence. Reversal of narcotic effect will precipitate acute abstinence syndrome. Repeat administration The patient who has satisfactorily responded should be kept under continued surveillance. Administer repeated doses as necessary, because the duration of action of some narcotics may exceed that of the narcotic antagonist. Respiratory depression Not effective against respiratory depression due to nonopioid drugs. 

Epidural/Intrathecal administration Limit epidural or intrathecal administration of preservative-free morphine and sufentanil to the lumbar area. Intrathecal use has been associated with a higher incidence of respiratory depression than epidural use. Asthma and other respiratory conditions The use of bisulfites is contraindicated in asthmatic patients. Bisulfites and morphine may potentiate each other, preventing use by causing severe adverse reactions. Use with extreme caution in patients having an acute asthmatic attack, bronchial asthma, chronic obstructive pulmonary disease or cor pulmonale, a substantially decreased respiratory reserve, and preexisting respiratory depression, hypoxia, or hypercapnia. Even usual therapeutic doses of narcotics may decrease respiratory drive while simultaneously increasing airway resistance to the point of apnea. Reserve use for those whose conditions require endotracheal intubation and respiratory support or control of ventilation. In these patients, consider alternative nonopioid analgesics, and employ only under careful medical supervision at the lowest effective dose. 

There are some additional choices in patients with refractory arthritis despite the use of NSAIDs or paracetamol (acetaminophen), alone or in combination. Narcotics can be used with little risk of addiction, but with the caveat that they can cause cognitive changes, constipation, urine retention and respiratory depression (see section on analgesics). Codeine... 

MAOIs have the most serious pharmacodynamic interactions of any antidepressant class. As discussed earlier, they can cause a hypertensive crisis and the serotonin syndrome. They potentiate the hypertensive effects of most sympathomimetic amines, as well as tyramine, which is the reason for the avoidance of over-the-counter preparations containing such agents, in addition to the tyramine-free diet ( 508, 509). The serotonin syndrome occurs most often when MAOIs are used in combination with SSRIs and venlafaxine but it can also occur when MAOIs are used with tryptophan, 5-hydroxytryptophan, and some narcotic analgesics. In addition, MAOIs can also significantly potentiate the sedative and respiratory depressant effects of narcotic analgesics. 

Fatalities due to acute BZD overdose alone are extremely rare. Nevertheless, fatal overdoses with triazolam in the elderly have been reported ( 192, 193). Even with ingestion of massive doses, recovery appears to be rapid and without serious complications or aftereffects ( 194, 195, 196 and 197). Combined ingestion of BZDs with other CNS depressants (alcohol, barbiturates, narcotics, orTCAs), however, may result in severe CNS and respiratory depression or hypotension. Severity of symptoms appears to depend more on the type and quantity of the other drugs than on the BZD plasma level (194, 195, 196 and 197). 

Side-effects Typical side-effects of tramadol are nausea, sweating and dizziness. In rare cases seizures after high i.v. doses are reported, mostly in combination with other proconvulsant componds or in patients with reduced seizure theshold (Gardner et al., 2000). Tramadol shows a reduced level of opioid side-effects, especially respiratory depression and constipation are less frequent and severe than with standard opioids such as morphine. Tramadol has a very limited abuse potential and is not subject to narcotic control (Cossmann et al., 1997). 

Individuals who have developed tolerance to opioids and who have overdosed on hydromorphone are not likely to develop the serious depression of the respiratory system that occurs in individuals with no such tolerance who have overdosed on hydromorphone. The typical treatment of narcotic overdoses with narcotic... 

This situation became particularly acute with respect to the development of illicit analogs of fentanyl to derive heroin substitutes. Fentanyl is a synthetic opioid, a p-receptor agonist, and is about 100-200 times more potent than morphine as an analgesic. As with other narcotic analgesics, respiratory depression is the most significant acute toxic effect of the fentanyl derivatives. Fentanyl analogs can be 80-1000... 

TCAs OPIOIDS 1. Risk of t respiratory depression and sedation 2. t levels of morphine 3. Case reports of seizures when tramadol was co-administered with TCAs 4. TCAs may t codeine, fentanyl, pethidine and tramadol levels 1. Additive effect 2. Uncertain likely t bioavailability of morphine 3. Unknown 4. TCAs inhibit CYP2D6-mediated metabolism of these opioids 1. Warn patients of this effect. Titrate doses carefully 2. Warn patients of this effect. Titrate doses carefully 3. Consider an alternative opioid 4. Watch for excessive narcotization... 

Rimazolium is a non-narcotic analgesic that strongly potentiates the analgesic and antagonizes the respiratory depressant effect of morphine alkaloids in animals and prevents the development of tolerance to morphine in animals and humans (1). Although rimazohum is not a new drug, experience with it is very hmited. 

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