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 This product received an effectiveness score of three and an amber safety classifaction

FLEXISEQ is a gel containing very small particles but no drug. It's used for osteoarthritis, particularly of the knee.

We asked an independent panel of experts in rheumatology, complementary medicines and nutrition to search and evaluate evidence on the safety and effectiveness of FLEXISEQ. Their assessment showed that from the scientific studies available we don’t yet understand how it works or whether it’s more effective than a completely inactive gel rubbed on to the knee.

We also don’t yet have enough information to say whether there any important safety issues, given the fairly small number of patients studied in the published clinical trials of FLEXISEQ to date.

What is it?

FLEXISEQ was first developed to carry drugs directly into the knee in order to ease the symptoms of osteoarthritis. It was then used as a comparator for studies in which some preparations were carrying active drug to the knee joint. Trial results have suggested that the particles may have positive effects when they don’t contain any drug.

You can buy FLEXISEQ from our online shop.

How does it work?

The manufacturers of FLEXISEQ claim that as the gel begins to dry, the very small particles seek out water and move through the skin into the knee joint. They claim that these particles attach themselves to cartilage, which helps to ‘lubricate’ the joint, reducing joint stiffness and helping with pain.

Other possible ways that it might work are that the particles absorb inflammatory chemicals or break down into chemicals which reduce inflammation and pain.

There haven’t been any scientific studies reported which have directly examined these theories, so at the moment we don’t understand how it might work.

Is it safe?

In the trials of FLEXISEQ, only a small proportion of participants using the gel reported side-effects. These were nearly always affecting the skin such as:

  • irritation
  • redness
  • a rash.

Only a fairly small number of participants have used FLEXISEQ in randomised controlled trials. Treatment during these trials lasted for just a few weeks, so we don’t know whether longer-term use is linked with safety issues.

We’ll have a better understanding of any safety issues when we have data from longer-term studies with more participants.

As FLEXISEQ doesn’t include any drug, it’s not expected that it would interact with other drugs. However, we don’t have enough data at the moment to be confident of this.


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