However, many people get lumps where the vein used to be and these can be quite tender. When the stocking comes off these lumps can either be seen or felt depending how deep they are.

These lumps are due to blood seeping back into the vein and being acted on by the foam sclerotherapy. This means that blood forms a small clot in the areas where the living vein used to be. We call this “trapped blood”.

As the blood breaks down it does two things. Firstly it pulls water in making it much more tense and tender. The second is, that if it is near the surface it can start to cause blue or brown stains on the surface.

Sometimes there is a red reaction on the skin and many nurses and GP’s think this is infection and give antibiotics. This is not the right thing to do as this is inflammation due to the trapped blood. The correct thing to do, is firstly, to take anti-inflammatory painkillers (Aspirin or similar) and secondly, at the correct time to release the trapped blood.

How is the trapped blood released?

The blood that is trapped just underneath the skin following the procedure is released using a needle. As this trapped blood has been pulling water into the area, it is under quite a lot of pressure. The trapped blood makes its way to the surface quite quickly. This is often helped by squeezing around the area such as when squeezing a spot.

You should note that it may be necessary to make quite a few pinpricks to make sure enough of the blood is released particularly if there are lots of lumps. This can be very tender and some people even feel that this is painful. However it is a lot less painful than leaving the trapped blood inside to cause further inflammation and staining!

The releasing of trapped blood is usually done 3 - 5 weeks after the injections, and if there is a lot of trapped blood, this might need to be repeated another 2 weeks after that time.

Occasionally the trapped blood is deep and an ultrasound is needed to make sure that the release is done adequately.