Opioid analgesics syndrome

Acute abstinence syndrome (withdrawal) - In chronic pain patients in whom opioid analgesics are abruptly discontinued, anticipate a severe abstinence syndrome. This may be similar to the abstinence syndrome noted in patients who withdraw from heroin. Severity is related to the degree of dependence, the abruptness of withdrawal, and the drug used. Generally, withdrawal symptoms develop at the time the next dose would ordinarily be given. 

The episode of unconsciousness was attributed to opioid toxicity in a patient in whom autonomic dysfunction may already have been present. It was suggested that opioid analgesics should be used with caution in patients with Guillain-Barre syndrome, because of the risk of hypotension consequent on autonomic dysfunction. 

Roca B, Mentero A, Simon E, Moulin DE, Hahn A, Hagen N. Pain and opioid analgesics in Guillain—Barre syndrome. Neurology 1998 51(3) 924. 

Cases of severe reversible neurotoxicity and parkinsonism are on record (SED-11,143) (SEDA-18, 82) (5,6). Severe nervous system syndromes may also result from interactions (see the monograph on Opioid analgesics). 

Drug interactions The most important drug interactions involving opioid analgesics are additive CNS depression with ethanol, sedative-hypnotics, anesthetics, antipsychotic drugs, tricyclic antidepressants, and antihistamines. Concomitant use of certain opioids (eg, meperidine) with MAO inhibitors increases the incidence of hyperpyrexic coma. Meperidine has also been implicated in the serotonin syndrome when used together with selective serotonin rcuptake inhibitors. 

Gnanadesigan N, Espinoza RT, Smith R, Israel M, Reuben DB. Interaction of serotonergic antidepressants and opioid analgesics is serotonin syndrome going undetected JAm Med... 

Risk of opioid-induced respiratory depression, nausea, vomiting, and constipation. Risk of monoamine excitabihty and possible serotonin syndrome. Tapentadol should not be used during breast feeding. Like other extended-duration opioids, the cost of tapentadol ER will probably be higher than immediate-release opioid analgesics. 

SSRIs OPIOIDS 1. Possible 1 analgesic effect of oxycodone and tramadol 2. T serotonin effects, including possible cases of serotonin syndrome, when opioids (oxycodone, pethidine, pentazocine, tramadol) are co-administered with SSRIs (fluoxetine and sertraline) 3. SSRIs may t codeine, fentanyl, methadone, pethidine and tramadol levels 1. Uncertain. Paroxetine inhibits CYP2D6, which is required to produce the active form of tramadol. 2. Uncertain 3. SSRIs inhibit CYP2D6-mediated metabolism of these opioids 1. Consider using an alternative opioid 2. Look for signs of T serotonin activity, particularly on initiating therapy 3. Watch for excessive narcotization... 

Meptazinol is a high-efficacy partial agonist it also has central cholinergic activity which add to its analgesic effect. It is used to relieve acute or chronic pain of moderate intensity, e.g. postoperatively and in obstetrics. Meptazinol does not cause euphoria and withdrawal effects seem not to occur when it is discontinued. It appears not to induce a withdrawal syndrome in opioid-dependent subjets. 

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