Nausea with opioids

Although many who experiment with opioids experience euphoria or symptom rehef with the first use, some experimenters use these drugs only a few times and then avoid further use because of an awareness of the risks or because of unpleasant side effects such as nausea or vomiting. Even for those... 

Another pharmacological approach is to reduce the intensity of the symptoms with the o2 adrenergic antagonist clonidine, which is normally used to treat hypertension. Overactivity of the locus coeruleus is associated with opioid withdrawal signs such as tachycardia, nausea, vomiting, and sweating. 

Hypotension was the most commomly reported side-effect. Co-administration with opioids may raise the incidence of hypotension, nausea, and pruritus (Scott et al., 1999). 

Fnrazohdone is used in the treatment of giardiasis. Its adverse effects are usually mild and transient abdominal discomfort, nausea, and vomiting. The urine may be dark-colored (SEDA-11, 597). Metabolites of furazolidone inhibit monoamine oxidase (1) and there is therefore the potential for interactions with foods containing tyramine (2) and with opioid analgesics hyperpyrexia has been reported in rabbits that were given fnrazohdone and pethidine (3). 

A strategy for controlling pain caused by malignant disease has been outlined and the classic effects that can be associated with opioid administration have been reviewed (6). These include constipation, nausea, sedation, pruritus, urinary retention, myoclonus, and respiratory depression. The latter can be life-threatening. Particular care is needed in opioid-naive individuals, those with compromised respiratory function, and elderly patients. 

The decreased gut transit time associated with opioids, when not desired, can cause severe constipation and even bowel obstruction. Patients do not usually develop tolerance to these effects of opioids, even after long-term treatment. Morphine is also associated with spasms in the bile duct and sphincter of Oddi and the bladder. At higher doses, nausea and vomiting related to the chemore-ceptor trigger zone in the fourth ventricle of the brain can be a limiting factor in opioid therapy. 

When used as monotherapy, IV acetaminophen does not cause excessive sedation, biliary spasm, respiratory depression, nausea, vomiting, ileus, or pruritus associated with opioids, nor the harmful cardiovascular, renal, gastrointestinal, and hematological effects associated with NSAIDs and COX-2 inhibitors. 

Hydromorphone binds to p opioid receptors in the central nervous system to produce dose-dependent analgesia. Binding at p receptors is also responsible for many of its its side effects including euphoria, pruritus, nausea, decreased GI motility, and constipation. Respiratory depression, the most troubling adverse event associated with hydromorphone, can be reversed with opioid antagonists such as naloxone. 

In an efficacy and safety trial of BTDS in opioid-exposed subjects with moderate to severe low back pain, the most frequently reported adverse events were those typically associated with opioid therapy (e.g. nausea, headache, vomiting, constipation, somnolence, dizziness) and application-site prittitus, typical of a transdermal delivery system [4]. BTDS treatments were found to be generally well-tolerated and safe. 

Side effects are similar to those observed with opioids constipation nausea central nervous system depression seizures (in conditions with lower seizure threshold)... 

The large numbers of opioid receptors in areas of the brainstem such as the solitary tract and adjacent areas are probably related to respiratory effects of opiates, cough suppression and nausea and vomiting. Opiates acting in the brainstem reduce the sensitivity of the respiratory centres to pC02 and this is the most common cause of death from overdose with street use of opiates. 

The adverse reactions include slowing of gastrointestinal propulsion with the ensuing risk of constipation, which can be prevented with lactulose or lactitol. Opioid treatment can also cause nausea and sometimes vomiting. There is also a dependence problem and a risk of respiratory depression. The latter may be a practical problem in anaesthetic practice or in overdose, but rarely in the case of treatment with slowly increased oral doses. The nausea is... 

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