Side effects of drugs are often misdiagnosed as symptoms of another medical condition, and the result is that patients are prescribed more drugs to treat adverse drug reactions (ADRs). Prescribing cascades contribute to polypharmacy, which has several associated risks, such as drug interactions, increased frequency or severity of side effects and poor medication adherence. They can also exacerbate the harmful effects of unrecognized ADRs, impact a patient’s quality of life and lead to avoidable hospital admissions and health system costs. Health practitioners should always investigate the possibility of an ADR presenting itself as a new symptom, especially in older adults, and avoid prescribing additional drug treatment until this possibility has been thoroughly investigated.
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There is no evidence to support the use of low-dose codeine pain medication over non-opioid analgesics. Codeine is an addictive opioid with potential for abuse and dependence. Over-the-counter codeine products are often supplied in combination with non-opioid analgesics (i.e., NSAIDs and acetaminophen). In addition to concerns regarding codeine abuse and dependence, misuse of these codeine-containing combination analgesics may also result in serious adverse effects due to high doses of the simple analgesics (ibuprofen, acetaminophen or aspirin). Effects of high doses of simple analgesics may include liver toxicity, gastric perforation, haemorrhage and peptic ulcer, renal failure, chronic blood loss anaemia and low blood potassium (with potential fatal heart and neurological complications).
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Two-thirds of Canadians over 65 take five or more different medications and more than 40% of seniors 85 and older take 10 or more drugs. With each new drug, the risk of adverse drug reactions and subsequent hospitalization of the patient increases. In order to ensure the safety and appropriateness of therapy, all health care practitioners should have access to the therapeutic indication for a patient’s drug therapy and start or renew medication only once they have determined that the benefits of therapy outweigh the risks to the patient.
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Proton pump inhibitors (PPIs) are among the most commonly prescribed drugs in Canada and many are becoming available as over-the-counter medications. While generally safe and well-tolerated for short-term use as needed in the treatment of gastro-esophageal reflux disease, PPIs can cause a number of adverse effects which may increase with a patient’s age, long-term use or when the drug is inappropriately prescribed. Some adverse effects associated with long-term use of PPIs include increased risk of fracture, Clostridium difficile infection and diarrhea, community-acquired pneumonia (CAP), vitamin B12 deficiency, and hypomagnesemia. Guidelines indicate a preference for short-term use, H2-receptor antagonists or lifestyle changes over the chronic use of PPIs, and recommend discontinuing PPIs in adults who have completed a minimum of 4 weeks of treatment and whose symptoms have resolved. This does not apply to patients with Barrett esophagus, severe esophagitis grade C or D, or a documented history of bleeding gastrointestinal ulcers.
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Between 2005 and 2012, the sedating properties of certain atypical antipsychotics have led to a 300% increase in their off-label use for insomnia. Guidelines report a lack of evidence of benefit for atypical antipsychotics as first-line therapy and warn against their possible adverse effects, including weight gain and metabolic disorders. While antipsychotics may be appropriate in some patients with insomnia who have not benefited from other treatments, the use of these medications as first-line therapy for insomnia is discouraged due to the lack of evidence of benefit and potential for harmful adverse effects.
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Benzodiazepines are commonly prescribed drugs in Canada for anxiety disorders and insomnia. Strong evidence shows that long-term use of benzodiazepines in elderly patients is associated with tolerance, dependence and adverse effects, including sedation, impaired memory and cognition, falls, hip fractures, depression and increased hospital admissions. Prescribing guidelines recommend exploring alternative non-pharmacological and pharmacological options prior to prescribing benzodiazepines. If determined to be beneficial for the patient, benzodiazepines should not usually be prescribed for long-term use and discontinuation strategies should be built into the patient’s treatment plan, such as gradual dose tapering, cognitive-behavioural therapy and alternative or tapering medications.
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