If you think you have fibromyalgia, visit your GP. Diagnosing fibromyalgia can be difficult, as there is no specific test that can diagnose the condition.

The symptoms of fibromyalgia can vary and are similar to those of several other conditions. 

During diagnosis, you will be asked about how your symptoms are affecting your daily life. Your body will also be examined to check for visible signs of other conditions – for example, swollen joints may suggest arthritis, rather than fibromyalgia.

Ruling out other conditions

If your GP thinks you may have fibromyalgia, they will first have to rule out all other conditions that could be causing your symptoms. These conditions include:

• chronic fatigue syndrome (also known as myalgic encephalomyelitis, or ME) – a condition that causes long-term tiredness
• rheumatoid arthritis – a condition that causes pain and swelling in the joints
• multiple sclerosis (MS) – a condition of the central nervous system (the brain and spinal cord) that affects movement and balance

The main tests used to check for these conditions are urine and blood tests, although you may also have X-rays and other scans. If you are found to have another condition, you could still have fibromyalgia as well.

Criteria for diagnosing fibromyalgia

In order for fibromyalgia to be diagnosed, certain criteria usually have to be met. The most widely used criteria for diagnosis are:

• you either have severe pain in three to six different areas of your body, or you have milder pain in seven or more different areas  
• your symptoms have stayed at a similar level for at least three months
• no other reason for your symptoms has been found

The extent of the pain used to be assessed by applying gentle pressure to certain "tender points", where any pain is likely to be at its worst. However, this is less common nowadays.

Diagnosing additional conditions

It's also possible to have other conditions alongside your fibromyalgia, such as:

• depression
• anxiety
• irritable bowel syndrome (IBS) – a condition that affects the digestive system

If your symptoms suggest you have another condition as well as fibromyalgia, you may need further tests to diagnose these. Identifying all possible conditions will help to guide your treatment.