Is It Just Fluid?

Is It Just Fluid… or Could It Be Lymphoedema?

After cancer treatment, it’s not unusual to notice changes in how your arm feels.

It might feel:

• heavy

• tight

• slightly full

• or just… different

Sometimes this comes and goes.

Sometimes it settles overnight.

Sometimes it doesn’t.

And that’s usually when people start to wonder:

Is this just fluid… or could this be lymphoedema?

• Not all swelling (or heaviness) is lymphoedema

Our bodies are constantly moving fluid in and out of tissues.

After activity, flying, gardening, heat, illness or even disrupted sleep, it’s possible for fluid to build up temporarily.

This is sometimes described as a temporary overload — where the lymphatic system is simply dealing with more fluid than usual for a short time.

In these cases:

• symptoms may improve with rest

• settle overnight

• reduce with gentle movement

You might find it helpful to read:
 [Why Does My Arm Feel Heavy After Cancer Treatment?]

But sometimes… the system’s capacity has changed

Treatments such as:

• lymph node removal

• radiotherapy to the chest or underarm

can reduce how easily fluid drains from the arm.

In simple terms:

Your lymphatic system may still be working —
but it may not have the same drainage capacity it had before treatment.

This means even normal amounts of fluid may begin to collect in the tissues.

Over time this can lead to:

• heaviness

• tightness

• swelling

• aching

• reduced movement

This is how lymphoedema can develop.

According to Cancer Research UK, lymphoedema can develop months or even years after cancer treatment and may begin with subtle symptoms such as heaviness or tightness before visible swelling appears.

You can find more information at Cancer UK

Early signs can be very subtle

Many people expect lymphoedema to be obvious — but early changes may include:

• jewellery feeling tighter

• sleeves leaving marks

• skin feeling less stretchy

• fingers feeling stiff

• a reduced sense of ease when moving your arm

The NHS also highlights that symptoms may come and go in the early stages.

At this stage:

There may be no visible swelling at all.

You might simply notice:

“It doesn’t feel like my other arm.”

• Why early support matters

When fluid begins to collect in the tissues, it’s not just water.

It also contains proteins and other substances which, if left unmanaged, may:

• trigger inflammation

• activate fibroblasts

• contribute to tissue changes over time

Over time, persistent fluid build-up may increase the risk of:

• tissue hardening

• reduced movement

• longer-term swelling

Which is why noticing changes early is often helpful — not because you’ve done something wrong, but because it gives you more options for support.

What can early support look like?

Depending on what’s happening, support might include:

• gentle, appropriate exercise

• building strength gradually

• supporting tissue glide with Scar Therapy

• or specialist treatments such as
   [Manual Lymphatic Drainage]

The aim is usually to:

• support fluid movement

• reduce build-up

• and prevent longer-term tissue changes where possible

This is often part of preparing your system before returning to more demanding activity — something many people don’t realise is even an option.

Sometimes heaviness is temporary.

Sometimes it’s a sign your lymphatic system needs a little more support following treatment.

Knowing the difference isn’t always straightforward — and it’s okay to ask questions if something doesn’t feel right.

Early advice may help you:

• feel more confident

• move more safely

• and reduce the risk of longer-term changes

If you’ve noticed:

• heaviness

• tightness

• or changes in how your arm feels

after cancer treatment — and would like to understand what support might be appropriate for you — you’re welcome to get in touch to discuss whether movement, self-care strategies, or specialist lymphatic support may be helpful.