Is paracetamol effective for low back pain?

The results of the trial showed that taking paracetamol made no difference to the amount of pain, ability to function, sleep or quality of life for people with acute low back pain, when compared with taking a placebo (a dummy pill).

The results were the same whether paracetamol was taken regularly or just as needed. Read more about how the trial was done.

The findings were surprising, because paracetamol is recommended by Australian and International guidelines as the first medicine to try for acute low back pain.^4,5

Should we believe the results?

Yes — it was a large, well designed randomised controlled trial.⁶

Because the trial was done in Australia, we can also be more confident that the results apply to our population.³

However, many researchers will likely want to see the study repeated in a different group of people with acute low back pain before dismissing paracetamol as an effective treatment.⁶

Could paracetamol still help some people?

The people in this trial had all sought help from a health professional for their back pain, so it is not possible to say that paracetamol is not effective for people who manage their back pain themselves.

Acute low back pain usually gets better on its own, and no treatment has been shown to improve the outcome much beyond its natural course.³

However, other medicines for pain relief include anti-inflammatory medicines (NSAIDs) such as ibuprofen (eg, Nurofen Tablets), aspirin (eg, Aspro Tablets) and diclofenac (eg, Voltaren Tablets). These may give a small amount of relief, but they are more likely to cause side effects than is paracetamol.⁸

Some people, including those with high blood pressure, asthma or stomach ulcers, or who take other medicines (eg, warfarin) have a higher risk of side effects from NSAIDs. Before taking any NSAIDs, including those bought over the counter, ask your doctor or pharmacist about the benefits and potential risks.

There are non-medicine treatments available for back pain, but many have not been studied in detail and so it is not known how helpful they are.⁸ However, this does not necessarily mean they will not help you to manage the pain. Ask your health professional about other treatments that might be right for you.

Acute low back pain can be severe and you may need to reduce your activities for a couple of days. However, resting longer than this in bed or on the couch is not going to help you recover more quickly.⁸

Keep moving

The sooner you start moving naturally again, the sooner your back is likely to start feeling better. Start with gentle activity and keep moving. Move about and stretch regularly. Avoid staying in one position — for example sitting at your computer, watching TV or lying down — for more than 20–30 minutes at a time.

Start slowly

With each day, try to move a little further or faster; slowly build up your level of activity within your normal day-to-day routine. Experiencing some pain when moving is normal, just take it slowly.

Return to work

Most people who experience acute low back pain do better if they return to work fairly quickly. This may mean returning to your job before your back feels completely better. You may need to modify the way you normally work until you feel better. Speak to your employer or doctor before your return.

Acute low back pain is rarely due to any serious injury, disease or damage to the spine and does not cause lasting damage. But you should see your doctor if the pain doesn’t improve over time or if you have any other unusual symptoms that worry you. Some examples are fever, difficulty passing urine, weakness, numbness or pins and needles in your legs.

Scans are unlikely to help

For most cases of acute low back pain, X-rays and other scans won’t show the cause of your pain and won’t help your recovery.⁹

The trial included over 1600 adults from Sydney, Australia, who had low back pain for less than 6 weeks, preceded by one month with no pain.³ They had at least moderate intensity pain, with or without leg pain.

Compared with placebo, neither regular, nor as-needed, paracetamol had a significant effect on pain, function, sleep or quality of life in people with acute low back pain.

People were not included in the trial if they had suspected serious spinal damage or currently used a regular, full-dose pain reliever.

The trial was designed to assess both regular and as-needed paracetamol. Participants were randomised to four weeks of either:

• regular doses of paracetamol, three times a day, totalling 3990 mg per day, plus a box of placebo tablets to take as needed
  
• as-needed paracetamol, to a maximum of 4000 mg per day, plus regular placebo tablets
  
• or placebo tablets taken regularly and as needed.