-The management of acute and chronic pain often includes opioid therapy. In both the acute and chronic pain settings, however, opioids have several disadvantages including risk of nausea and vomiting, somnolence, constipation, respiratory depression, androgen deficiency, physical dependence, and tolerance. Opioid medications also carry a risk of abuse or addiction by either the patient or non-medical users. For these reasons, consideration of non-opioid strategies for pain management is beneficial. While opioids will certainly continue to have a place in pain management despite their disadvantages, the use of non-opioid medication options may limit the amount of opioid necessary or even result in improved pain control. In fact, given that the majority of both acute and chronic pain is thought to be complex and multi factorial, a multi modal analgesic approach is ideal for management. Acetaminophen is typically considered first-line therapy for chronic pain conditions, including osteoarthritis (OA) and chronic pain associated with total knee arthroplasty. However, many times patients are treated inappropriately with opioids instead.
Acetaminophen is considered first-line treatment for many pain conditions because of its safety advantages. Compared with other analgesics available, acetaminophen is associated with very few adverse events and is considered safe to use chronically. Healthcare providers strive to “first do no harm. Therefore, for most chronic pain conditions, a trial of acetaminophen should be used and monitored for effect before initiating other analgesics, including opioids. However, acetaminophen is not without risks. Safety concerns associated with acetaminophen include serious liver damage if ingestion is greater than the recommended total daily dose of 4,000 mg. Long-term high doses of acetaminophen and accidental overdose from inadvertently consuming multiple acetaminophen products are the leading causes of acute liver failure in the U. S. For this reason it is important that the patients who are utilizing acetaminophen chronically for pain are educated on proper dosing and administration, and are aware of any other acetaminophen-containing products they may use. The disadvantage of acetaminophen is that it often cannot provide a sufficient analgesic effect and does not exert a specific anti-inflammatory effect, causing many patients to discontinue or switch therapies.
Dowell D, Haegerich TM, Chou R. CDC guideline for prescribing opioids for chronic pain United States, 2016. MMWR Recomm Rep. 2016; 65(1):1-49.