By Mr Ahmed-Ramadan Sadek, Neurosurgeon · Last reviewed October 2026 · 6 min read

What do we mean by acute back pain?

Doctors use the term acute low back pain for pain felt anywhere from the bottom of the ribcage down to the crease of the buttocks, where the episode has lasted for less than six weeks. “Acute” refers only to how long it has been going on, not to how severe it is.

According to the British Association of Spine Surgeons (BASS), around 80% of people have back pain at some stage in their lives, and up to half of the population will experience an episode in any given year.

The reassuring news is that the great majority of attacks improve on their own. What most people really want to know is how to recover faster, and how to lower the chance of it coming back. That is what this guide focuses on.

What does it feel like?

Acute back pain varies a great deal. Some people have a nagging ache now and again, take the odd painkiller and carry on with their day. Others have a sudden, severe attack in which the back muscles go into spasm and they feel “locked” or stuck in one position, unable to straighten up.

A locked back can be alarming, but the muscles always release in time. The aim is to help them let go sooner, so that you can get back to your normal routine. The two things that make the biggest difference are good pain control and getting moving early.

What causes it?

Usually no single cause can be pinned down, and that is normal. The pain generally comes from the muscles, ligaments, small joints and discs of the lower back, which can all hurt without being seriously damaged. This is called non-specific back pain: real pain, but not from a dangerous condition.

Less commonly, leg pain travelling below the knee suggests that a nerve is being irritated, for example by a slipped disc causing sciatica. Serious causes such as infection, cancer or severe nerve compression are uncommon, and your doctor will check for clues that point to them.

How can I ease the pain?

Taking pain relief regularly, rather than waiting until the pain is unbearable, makes it much easier to stay mobile. Many people find that ordinary over-the-counter medicines work well, especially when two types are combined, because they act in different ways.

• Paracetamol works both in the brain and where the pain arises. Being cheap and widely sold does not make it weak; studies suggest it can be genuinely effective for back pain.
• Ibuprofen is an anti-inflammatory that also relieves pain. For most adults, BASS suggests 400 mg three times a day alongside paracetamol 1 g, taken fairly regularly until the pain has clearly eased.
• If these are not enough, a short course of a stronger painkiller containing codeine may help. Some are available from a pharmacist; anything stronger needs a prescription.

Many people worry that painkillers will “hide” the pain and let them injure themselves. This is not the case. Your body has powerful protective reflexes, and simple pain relief does not switch them off. In the same way that a paracetamol would never let you keep your hand in hot water, it will not let you harm your back by moving about.

Why keeping active matters

For many years people were told to rest in bed. We now know this is unhelpful. Controlled trials comparing a couple of days of bed rest with simply carrying on as normally as possible found that resting does not speed recovery, and current advice is to avoid it.

You do not need to wait until you are completely pain-free before going back to your usual activities or to work. Building up gradually, even while you still have some discomfort, tends to shorten the episode. A helpful phrase to remember is: it may hurt, but you will not harm it.

• Change position often and avoid sitting still for long stretches.
• Take short, frequent walks and increase the distance as you feel able.

Do I need physiotherapy, a chiropractor or an osteopath?

BASS notes that hands-on treatments do not appear to make a large difference during the first four weeks or so, largely because most episodes are already getting better by themselves in that time. The most valuable thing a health professional can usually offer early on is a careful assessment, reassurance that nothing serious is going on, and clear, consistent advice. Stick to trustworthy, non-commercial sources of information.

Do I need a scan?

Usually not. A scan cannot show where ordinary back pain comes from and often reveals harmless age-related changes. Imaging is kept for people with warning signs, or when surgery is being considered. Our guide to MRI scans of the spine explains more.

Warning signs doctors look out for

Doctors use a short list of “red flags” that suggest a more detailed assessment or tests might be sensible. Having one does not mean something serious is wrong, but you should see your GP promptly if any of the following apply:

• You have had cancer in the past, or have previously had surgery for cancer.
• You are losing weight without trying.
• The pain keeps getting worse despite taking good pain relief.
• You are at higher risk of infection, for example after recent high-dose steroids, while taking anti-rejection medicines, if you inject drugs, or if your immune system is weakened (such as by HIV).
• This is your first episode of severe back pain and you are over 55.
• The pain wakes you at night and stops you getting back to sleep.

What can slow recovery?

Alongside red flags, clinicians talk about “yellow flags”. These are not signs of disease but obstacles that can get in the way of recovery. Most can be overcome, though some people need extra support, and tackling them early can prevent long-term disability if pain continues beyond about four weeks.

Many yellow flags are fears about pain: worrying about ending up in a wheelchair, or avoiding everyday activities in case they make things worse. Frightening stories from well-meaning friends can feed these fears. Much of what was once believed about back pain has turned out to be wrong, and modern approaches get people back to normal life far sooner.

Outlook

Most episodes of acute back pain improve, often within days to a few weeks. Keeping your pain under control, staying active and returning to normal life as soon as you can give you the best chance of a quick recovery. If your pain is not settling after several weeks, or it keeps coming back, it is worth seeing your GP or a spinal specialist for a fuller assessment.

• BASS patient information: Acute back pain
• BASS patient information: Cauda equina syndrome
• NHS: Back pain
• Spinemathema guide: Cauda equina syndrome
• Spinemathema guide: MRI scans of the spine

This guide is general information and is not a substitute for advice about your own situation. Please speak to your GP or specialist.