December 2, 2022

Review raises questions about paracetamol as common pain reliever


Paracetamol is sold as the world’s leading brand name drug for the relief of mild to moderate pain, but a close review of existing studies conducted by the University of Sydney shows that it is not known to what extent. Over the counter pain reliever works for the majority. of the conditions for which it is taken.

Most reviews to date (22 of 36 in this systematic review) have evaluated only single doses of the pain reliever, while it is common for consumers to take many doses during self-treatment. .

“This means that there is a gap in our knowledge about the effectiveness of the pain reliever commonly used for a range of painful conditions,” said co-lead author Dr Christina Abdel Shaheed.

This new systematic review found evidence of effectiveness for only four conditions – including general headaches – but found it to be ineffective for lower back pain despite its popularity for common musculoskeletal conditions.

The review also points out that the widely held opinion that paracetamol is safe can be based on short-term use at the recommended dose and suggests that pain is best treated holistically.

The journal was published today in the Australian Medical Journal in addition to an accompaniment function in MJA Insight +.

Main conclusions:

  • Paracetamol has only been shown to be effective as an analgesic for four conditions studied: osteoarthritis of the knee or hip; tension headache (general, no migraine); perineal pain after childbirth (between the anus and the genital area); and craniotomy (removal of part of the skull); the effect for these conditions was modest.
  • The evidence for low back pain is that it does not provide better results than placebo; however, the healing effect of time could be confused with the effectiveness of a drug.
  • For other conditions, for example abdominal pain, pain during dental procedures, migraines and middle ear infections, it was not clear whether paracetamol relieved the pain.
  • Most of the studies to date have only looked at a single dose (taken all at once, i.e. 1 to 2 tablets), while paracetamol is usually taken more than once to treat a condition. symptom.

Paracetamol is listed in the 2017 ranking of the World Health Organization List of essential drugs and is considered “essential to meet the world’s most important public health needs”. It is commonly used to treat muscle or joint pain, pain caused by injury or surgery, headaches, general body aches, or cancer pain and is a very common treatment for chronic or persistent pain.

The study did not examine the use of paracetamol to lower the temperature.

Lead authors Dr Christina Abdel Shaheed and Dr Giovanni Ferreira of the Institute for Musculoskeletal Health at the School of Medicine and Health, University of Sydney, said that given the widespread use of pain relief pain, Australian researchers looked at all the reviews of clinical trials testing the ability of paracetamol to relieve pain. This systematic review consisted of 36 reviews (over 19,000 participants) covering 44 painful conditions.

“This review brings together for the first time all existing evidence on the effectiveness of paracetamol for treating pain in one document,” said Dr Abdel Shaheed, School of Public Health.

“For tension headaches, we know paracetamol works better than placebo – but for most other conditions, we just lack the evidence to be able to make strong or definitive claims about the effectiveness of paracetamol,” he said. she declared.

Doctor Giovanni Ferreira added: “What is clear is that paracetamol does not effectively relieve back pain or most types of osteoarthritis, which calls for research into strategies that will help people with musculoskeletal pain. . “

Lead author and Institute director Professor Chris Maher said it was easy to mistakenly attribute pain relief to the use of paracetamol.

“From research, we know that the biggest contributor to improving low back pain is probably natural history; in other words, back pain often gets better on its own. Even with a chronic disease like osteoarthritis it fluctuates and if you seek care when it is bad it will likely improve anyway; this is precisely why we need controlled trials, ”he said.

Co-author Professor Andrew McLachlan, Dean of the Sydney Pharmacy School, said the review highlighted the limitations of focusing on single-dose trials, to explore efficacy in reducing the intensity of different types of short-term painful conditions.

“The single-dose study designs provide little help in understanding the possible effects of paracetamol in people with persistent painful conditions and regularly using paracetamol for pain control,” he said.

Dr Abdel Shaheed concluded that people should not rely on pain relievers as a stand-alone treatment for pain relief.

“Any pain medication should be seen as part of a holistic plan of care, along with strategies like exercise, physiotherapy or other lifestyle changes. A conversation with the doctor or pharmacist can be a good way to help people know what alternatives, subsidized or not, are available to them, ”said Dr Abdel Shaheed.

About paracetamol:

  • Observe the safety limits for the use of paracetamol (maximum 4 g per day for adults, which will vary depending on the formulation used).
  • Keep in mind that there are different types of paracetamol products (long acting which is usually higher dose versus short acting i.e. standard 500mg tablets in Australia ); and cold and flu preparations (including decongestants) and popular over-the-counter pain relief products (including ibuprofen) may also contain paracetamol.
  • Do not use paracetamol for more than a few days in a row, unless directed otherwise by a doctor or pharmacist.
  • Consider combining the medication with other non-drug strategies to optimize pain relief.