Ep 126 EM Drugs That Work and Drugs That Don’t – Part 1: Analgesics

This is EM Cases Episode 126 Emergency Drugs that Work and Drugs that Don't Part 1 - Analgesics with Dr. Joel Lexchin and Dr. Justin Morgenstern. In this podcast we discuss the key concepts in assessing drug efficacy trials, and provide you with a bottom line recommendation for the use of gabapentinoids, NSAIDs and acetaminophen for low back pain and radicular symptoms, topical NSAIDs and cyclobenzaprine for sprains and strains, caffeine as an adjunct analgesic, why we should never prescribe tramadol, dexamethasone for pharyngitis, calcium channel blockers for hemorrhoids and anal fissures, buscopan for abdominal pain and renal colic and why morphine might be a better analgesic choice than hydromorphone... Podcast production, sound design & editing by Anton Helman Written Summary and blog post by Anton Helman June, 2019 Cite this podcast as: Helman, A. Lexchin, J. Morgenstern, J. EM Drugs That Work and Drugs That Don't - Part 1: Analgesics. Emergency Medicine Cases. June, 2019. https://emergencymedicinecases.com/drugs-that-work-analgesics. Accessed [date] Go to part 2 of this 2-part podcast on EM drugs that work and drugs that don't Key concepts in assessing drug efficacy trials Risks of bias and industry sponsorship in drug trials Industry sponsored clinical trials are more likely to produce positive results and positive conclusions compared to trials with other forms of sponsorship [1]. Authors with financial ties to companies that make the drug vs. authors without ties portends an odds ratio of almost 3 for a positive study [2]. It is important to assess whether there are any conflicts of interest of authors for any drug trial that you read as there are subtle ways in which conflicts of interest can bias a trial. Consider using a checklist appraisal tool when reading drug trials so that subtle bias is more easily recognized. Harms are often under-represented in trials A systematic review compared the number of adverse events in matched published and unpublished studies. Relying only on published studies would have missed between 43% and 100% of adverse events [3]. A study of 6 general medical journals showed that of all the published RCTs in those journals there was no information on severe adverse events in 27% of trials and no information on withdrawal of patients due to an adverse event in 47% [4]. Some of the reasons why harms are often under-represented in trials include the huge cost of a large enough trial to detect harms, that many harms occur years later -  long after the trial is completed, some trials include a 'run-in' period where all patients receive the drug and patients with major side effects are excluded from the subsequent randomized trial, and some serious harms are rare enough that the trial will not be powered to detect the harm. An important concept is that while benefit is relative depending on the population studied, harms are static across populations. It is thus important to consider whether or not the population in the trial is similar to the population of patients that you are treating. When reading trials, remember that harms are often under-represented. Lack of replication of study results Perhaps because of the medical communities desire to find drugs that work, we often become overly optimistic about the positive results of a trial and don't see a need to replicate the study results. Conversely, when multiple trials show negative results and subsequently one trial shows positive results, we tend to believe the positive results at the exclusion of the other trials.