Opioid constipation side-effects

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. 

The appeal of NSAIDs, COX-2 inhibitors, and acetaminophen is that the unfavorable opioid-related side effects may be mitigated. Although opioids are potent and effective drugs for pain control, they are well known for adverse side effects such as excessive sedation, dose-dependent respiratory depression, pruritus, nausea, vomiting, biliary spasm, hypotension, constipation, and urinary retention. Minimizing these effects has the advantage of earlier ambulation post-operatively and consequently a shorter hospitalization, as weU as higher patient satisfaction and quality of recovery. 

It is now widely accepted that there are at least three opioid receptor sub-types, mu kappa and delta. During the last decade increasing evidence has accumulated to support the hypothesis that a selective kappa opioid agonist will be a powerful analgesic without the clinically limiting side-effects that characterise morphine (e.g., respiratory depression, constipation, addiction)... 

These differences in the behavioural properties of the opioid receptor sub-types are of considerable interest because the clinical use of currently marketed opioid analgesic drugs is limited by their undesirable side-effects, which include respiratory depression, constipation and an abuse or dependence liability. These side-effects have been associated with mu receptor ac-... 

Tramadol is an opioid analgesic, which acts by exerting an opioid effect and through the stimulation of adrenergic and serotonin pathways. Compared with the other opioids, tramadol is less likely to cause the typical opioid side-effects, such as respiratory depression, and constipation. It is also less likely to cause addiction. 

Co-codamol is a combination of paracetamol (nonnapioid analgesic) and codeine (opioid analgesic). One of the side-effects of opioids is constipation. Naprosyn is a proprietary (trade name) preparation of the non-steroidal antiinflammatory drug naproxen Adalat is a proprietary preparation of the calcium-channel blocker nifedipine Amoxil is a proprietary preparation of the beta-lactam amoxicillin and Dulco-lax is the brand name of the stimulant laxative bisacodyl. 

One of the main side-effects of opioid analgesics, such as codeine and tramadol, is constipation. Amitriptyline (tricyclic antidepressant) and orphenadrine tend to have antimuscarinic properties, resulting in side-effects such as constipation. Senna is a stimulant laxative indicated in constipation. 

Reduced motility and secretion can lead to constipation, which is the most common side-effect of chronic opioid treatment (Mancini and Bruera, 1998). Opioid-induced constipation can increase to the stage of megacolon or paralytic ileus. Therefore chronic opioid treatment should be accompanied by concomitant use of laxatives. Besides their peripheral actions, opioids are involved in the central... 

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). 

Consistent with these hypotheses is the finding that continuous infusion of the opioid into the epidural or intrathecal space provides optimal pain relief postoper-atively or in chronic, intractable pain.2 40 83 Continuous infusion is associated with certain side effects, especially nausea and constipation, as well as the potential for disruption of the drug delivery system.24 57 77 Problems with tolerance have also been reported during continuous administration,27 but it is somewhat controversial whether tolerance really develops when these drugs are used appropriately in the clinical management of pain (see section on Concepts of Addiction, Tolerance, and Physical Dependence ). Hence, the benefit-to-risk ratio for continuous epidural or intrathecal infusion is often acceptable in patients with severe pain. This method of opioid administration continues to gain acceptance.24 57... 

The tendency for these drugs to produce constipation is another side effect that could have important implications for patients receiving physical rehabilitation. Opioid-induced constipation is especially problematic in patients with spinal cord injuries or other conditions that decrease gastrointestinal motility. In such patients, opioids are often administered along with laxatives and GI stimulants (see Chapter 27) to minimize the constipating effects and risk of fecal impaction. Therapists should therefore be aware of these constipating effects and help educate patients and their families so that these effects do not result in serious problems. 

The primary side effects with these drugs are nausea, abdominal discomfort, constipation, and other GI disturbances. Drowsiness, fatigue, and dizziness have also been reported. Although addiction is a potential problem when opioids are administered, the risk of tolerance and physical dependence is fairly small when these drugs are used in recommended dosages for the short-term treatment of diarrhea. 

Hydromorphone has comparable side effects to those produced by morphine use. This is true for sedation, respiratory depression, and constipation, but hydromorphone is associated with less vomiting than morphine. Nausea caused by hydromorphone and other opioids can be minimized by administering the drug along with food and having the patient lie down following administration. 

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. 

The opioids inhibit intestinal tract motility, which may cause constipation. This is one of the most common side effects encountered with the narcotic analgesics. If constipation becomes problematic, it can often be relieved by a regimen consisting of docusate sodium (Colace), 50 to 300 mg/day, and senna, two tablets twice daily. 

Stool softeners and cathartics can be used in children, as in adults, to relieve symptoms of constipation. Nausea and vomiting generally diminish as opioid therapy is continued, but antihistamines with antiemetic effects, such as hydroxyzine or promethazine, may be helpful as adjuvants to diminish impleasant G1 symptoms. Reducing the opioid dose to minimal analgesic levels may help to limit sedation or drowsiness. Mild respiratory depression, an uncommon side effect in children, may require only that the opioid dose be reduced. 

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. 

Fentanyl is used chronically in the management of major pain in humans. One of the common side effects of therapy with opioids is constipation. However, a recent cohort analysis of a large California HMO looking at the incidence of constipation in patients receiving opioid analgesics showed a low incidence of constipation in the patients receiving fentanyl patches (3.7%). 

Constipation related to medication action or side effect. Intestinal movement is reduced when opioids such as morphine sulfate are administered to the patient. 

Opioid antagonists (Table 7.4), predominantly naloxone, are used clinically to reverse the effects of opiates in overdose or postoperative sedation. Naltrexone, which has oral bioavailability, is used for the treatment of narcotic addiction and alcohol dependence. As discussed below (Section 2.2.2.1), peripherally selective antagonists are being evaluated for treatment of constipation and other gastrointestinal side effects associated with opioid agonist use. 

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