Opioids nausea/vomiting

OBD comprises a constellation of GI symptoms including OIC, incomplete evacuation, inhibition of gut peristalsis, bloating, pain, nausea/ vomiting, and increased gastric reflux and tone of intestinal sphincters [3]. Approximately 40% of patients taking chronic opioids for nonmalig-nant pain develop bowel dysfunction [25]. 

Opioid-like adverse effects such as nausea, vomiting, dizziness, constipation, headache, and somnolence are common. 

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. 

Opioids cause side effects that limits their use. They include respiratory depression, nausea, vomiting, constipation, a heightened level of blood pressure, urine retention, perspiration, and itching of course, the most dangerous of these is respiratory depression. Opioids cause dependency and addiction. 

Direct toxic effects of the opioid analgesics that are extensions of their acute pharmacologic actions include respiratory depression, nausea, vomiting, and constipation (Table 31-4). In addition, tolerance and dependence, diagnosis and treatment of overdosage, and contraindications must be considered. 

Side-effects Dezocin induces j-opioid-type side-effects with nausea, vomiting and drowsiness. Overdoses may be treated with naloxone. The compound has a low abuse potential and is not under narcotic control. Because of its partial antagonistic properties dezocine can precipitate withdrawal in opioid-dependent subjects (Strain et al., 1996). 

Side-Effects The most common side-effects are nausea, vomiting and dizziness. Other vegetative side-effects include sweating, hypotension and drowsiness. The compound is reported to be relatively free of respiratory depressant activity, which was attributed to selective binding to a subtype (p-1) of the opioid receptor... 

Side effects typically seen when opioids are used for PCA include sedation, pruritus, and gastrointestinal problems (nausea, vomiting). The incidence of these side effects, however, is not significantly increased during PCA versus more traditional methods of opioid administration such as intermittent intramuscular dosing.18 Respiratory depression is another common side effect of opioid use, but again, there is no increased incidence of this problem when appropriate amounts... 

Because the pharmacologic action of the opioids is complex and can result in either CNS depression or stimulation, it is difficult to predict side effects in given patients. Clinicians should note that at equipotent analgesic doses, all commonly used opioids produce similar degrees of side effects. However, these side effects are usually mild and do not necessitate discontinuing opioid therapy.The most commonly encountered adverse effects include lightheadedness, dizziness, sedation, nausea, vomiting, constipation, and respiratory depression (Box 7-2). These symptoms occur more often in ambulatory patients, in patients without severe pain, and in patients with kidney or liver dysfunction. 

Opioid-induced nausea, vomiting and dysphoria may interfere with any of the desired effects. 

Relief of pain after surgery can be achieved with a variety of techniques. An epidural infusion of a mixture of local anaesthetic and opioid provides excellent pain relief after major surgery such as laparotomy. Parenteral morphine, given intermittently by a nurse or by a patient-controlled system, will also relieve moderate or severe pain but has the attendant risk of nausea, vomiting, sedation and respiratory depression. The addition of regular paracetamol and a NSAID, given orally or rectally, will provide additional pain relief and reduce the requirement for morphine. NSAIDs are contraindicated if there is a history of gastrointestinal ulceration of if renal blood flow is compromised. 

Loperamide (tV 10 h) is structurally similar to diphenoxylate. Its precise mode of action remains obscure but it impairs propulsion of gut contents by effects on intestinal circular and longitudinal muscle that are at least partly due to an action on opioid receptors. Loperamide may cause nausea, vomiting and abdominal cramps. Its potential for abuse appears to be low. 

In a retrospective review of 37 patients with chronic non-malignant pain (mostly from failed lumbosacral spine surgery) treated with intrathecal hydromorphone there was an analgesic response in six of the 16 patients who were switched from morphine to hydromorphone because of poor pain relief (1). Opioid-related adverse effects, such as nausea, vomiting, pruritus, and sedation, were also reduced by hydromorphone in the 21 patients who were switched to hydromorphone because of morphine-related adverse effects, especially 1 month after use. These results should be treated cautiously, because of the limitations of a retrospective study that lacks strict inclusion criteria, with obvious population bias and under-reporting, and without standardized procedures for rotation to hydromorphone. 

Naltrexone 50 mg/day has been used to relieve pruritus in cholestatic liver disease in five patients (7). Pruritus scores fell, but two patients developed severe nausea, vomiting, light-headedness, or tremor, requiring withdrawal of treatment. The reviewers commented that these reactions may or may not have been related to opioid withdrawal and that the trial had had several design limitations. They pointed out that one concern relating to the chronic use of high-dose naltrexone is an asymptomatic rise in serum transaminases, although the doses used in this study have not been reported to produce liver function abnormalities. 

Nefopam, an orphenadrine derivative, is a centrally acting non-opioid analgesic. Various adverse effects have been reported, including nausea, vomiting, epigastric pain, dizziness, drowsiness and mental confusion, hypotension, tachycardia, skin rashes, xerostomia, and urinary retention some of these may be related to its anticholinergic properties (SEDA-11, 100). Its unsatisfactory adverse effects profile was confirmed in two studies of pain control in cancer and rheumatoid arthritis (SEDA-15, 104)... 

Antagonists Naloxone 1.5-3 pg/kg repeated Intravenous 1.1 Reversal of opioid-induced Nausea, vomiting, hypertension, cardiac... 

When an opioid is used as the sole agent by the epidural or intrathecal route, the results are disappointing, because of unwanted adverse effects, such as pruritus, nausea, vomiting, respiratory depression, and effects on the neonate, caused by significant systemic absorption (SEDA-17, 85). Hypotension and changes in fetal heart rate are not uncommon (SEDA-21, 91). Combinations of opioids (alfentanil, fentanyl, morphine, sufentanil) with local anesthetics (for example bupivacaine) have therefore been suggested to yield better results (SEDA-18, 83). 

Adverse reactions Sedation, respiratory depression, constipation, myoclonus, nausea, vomiting, flushing. Itching, miosis, hypotension, and hallucinations. Tolerance develops to all side effects with the ception of constipation and miosis. Physical dependence may develop within 5 days of opioid use. 

Depressant effects on the CNS are the most profound. Nausea, vomiting, and miosis may develop within Ih. Infants and children may demonstrate unusual sensitivity while habituated adults may have extreme tolerance to opioids. In children, greater... 

Chronic use of high doses of glutethimide may produce psychological and physical dependence. Abrupt discontinuation of therapy may result in withdrawal signs and symptoms such as nausea, vomiting, tremulousness, tachycardia, fever, delirium, hallucinations, and seizures. Unlike opioid withdrawal, glutethimide withdrawal can be life threatening. 

Acute toxicity induced by pentazocine is primarily associated with central nervous system (CNS) effects that include dizziness, anxiety, hallucinations, mood alterations, and seizures. Respiratory depression, increased PaCOi levels, pulmonary edema, and apnea may occur. Tachycardia, increased systolic and diastolic blood pressure, pinpoint pupils, nausea, vomiting, and abdominal pain have also been reported. In a recently published case series, 40% of acute pentazocine overdose patients did not have the classic opioid toxidrome of CNS and respiratory depression with miosis. 

The availability of new routes of administration have led to increased utility and decreased opioid adverse drug reaction risk. Epidural and intrathecal administration through spinal catheters produces adequate regional analgesia at relatively low total doses compared with intravenous or oral routes. As such, spinal administration can thus minimize somnolence, nausea, vomiting, and respiratory depression associated with these medications. Other alternative routes include intranasal administration of butorphanol, and rectal and transdermal administration of fentanyl [28]. Availability of such options provides not only a decreased risk of adverse reactions, but also more comfortable measures for patients who would otherwise require continued intravenous administration, or for those who are unable to receive oral medication [28,29]. 

Opioids share related pharmacologic attributes and exert a profound effect on the CNS and gastrointestinal tract. Mood changes, sedation, respiratory depression, nausea, vomiting, decreased gastrointestinal motility, dependence, and tolerance are evident in varying... 

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