Cochrane investigators published their findings on the efficiency of the most commonly used painkillers in their latest edition of The Cochrane Library, which will enable doctors and patients to decide which analgesics to use. Approximately 350 individual studies were conducted on ca. 45,000 patients to evaluate the potential efficacy of commonly used painkillers at specific doses.

Acute pain arises following damage to the tissue caused either by an injury or as a result of surgery. After surgery the pain felt occurs due to tissues becoming inflamed and giving analgesics is a key factor of good patient care. Controlling pain well assists in keeping patients as comfortable as possible and helps in their recovery.

The discoveries of 35 Cochrane Reviews of randomized trials investigating how effective various pain killers are when used against postoperative pain were examined by Dr Andrew Moore and colleagues working at the Oxford Pain Research Unit at Oxford University.

Moore explains:

“Our aim was to bring all this information together, and to report the results for those drugs with reliable evidence about how well they work or any harm they may do in single oral doses.”

A crucial discovery was that not one drug produced high levels of pain relief in all patients. “If the first pain killer a person tries doesn’t seem to be working, then a doctor should look to find an alternative reliable drug and see if it is more effective in that individual patient. There are plenty of options that have a solid evidence base,” says Moore.

Between different pain killers, the range of results varies significantly. In some cases, such as taking 120mg etoricoxib, or the combination of 500mg paracetamol in conjunction with 200mg ibuprofen, more than 70% of patients who took a single-dose for moderate or severe acute pain achieved good pain relief. With other drugs, such as 100mg aspirin and 600mg paracetamol taken on their own, only 35% of patients had good pain relief. The worst pain killer was codeine, with only 14% getting significant pain relief. The time in which the pain was relieved also varied significantly, from approximately 2 hours to around 20 hours.

Moore states:

“Pain relief doesn’t have to be a mystery. There is a body of reliable evidence about how well 46 different drug/dose combinations work against acute pain, but the review also shows there are many examples of drugs for which there is insufficient evidence, and the drugs in question should probably not be used to treat acute pain.”

Written by Grace Rattue