Some amount of fluid around your knee is necessary — it helps cushion your bones and keeps the joint limber. But if too much fluid accumulates, it can lead to an effusion and cause pain, swelling and stiffness. Luckily, knowing how to get rid of fluid on the knee can help relieve this discomfort.
Here's everything you need to know about fluid on the knee, including why it happens and how to remove fluid from your knee.
Video of the Day
What Is a Knee Effusion?
A knee effusion occurs when the joint swells with fluid, according to the Cleveland Clinic. It can cause symptoms like:
- Trouble moving the joint
- A feeling of heaviness in the joint
- Warm skin
What Causes Fluid Buildup in the Knees?
There are a number of reasons you can develop fluid in your knee. Per the Cleveland Clinic, the most common causes are:
Is Fluid on the Knee Serious?
Well, it depends on the cause of the effusion. For instance, sometimes resting, heating and icing the area is all that's needed to take care of fluid that accumulates as the result of overuse, per the Cleveland Clinic.
That said, you should visit your doctor if you experience severe pain, an obvious injury or any of the following issues:
- Inability to move your joint
- Inability to bear weight on your joint
- Loss of feeling in your joint
If you have a chronic underlying condition like arthritis or gout, you might not be able to get rid of effusions for good. Fortunately, though, there are treatments to help ease or prevent excess water in the knee if you regularly deal with this issue (more on that later).
Will Fluid on the Knee Go Away?
Again, how long water on the knee lasts depends on the cause of the buildup.
In some cases, fluid on the knee does go away by itself. For instance, if the cause of the effusion is temporary — like an injury — then the fluid should subside once you've healed, according to the Cleveland Clinic. How long that takes depends on the severity of your injury.
But if you have an underlying disease that contributes to the effusion, then you may not be able to eliminate your symptoms entirely.
How Can You Tell the Difference Between Fluid in the Knee and Other Swelling or Inflammation?
It can be tricky to tell if your knee pain or swelling is the result of an effusion or something else, as many knee issues cause similar symptoms.
The best way to determine the cause of your discomfort (and how to treat it) is to visit your doctor, per the Cleveland Clinic.
How Do You Get Rid of Fluid on the Knee?
The best treatment for an effusion depends on the cause. Here are some of the most common solutions:
Rest and Elevate
One of the main ways to reduce fluid in the knee joint is to rest — especially if the cause of the effusion is overuse or injury, according to the Cleveland Clinic. That means holding off on activities and perhaps even using support while you walk, like a cane.
Apply Cold or Heat
Applying cold or heat to your knee may help reduce pain and fluid buildup, particularly if you have an injury or arthritis, per the Cleveland Clinic.
When using ice or freezer packs, don't place them directly on the skin — instead, wrap them in a towel before placing them on your knee.
What Happens if Water on the Knee Is Left Untreated?
What happens to your knee depends on the underlying cause of the effusion. But in general, neglecting to rest and treat your joint likely won’t contribute to any healing, according to the Cleveland Clinic.
Whether the cause of your pain is an injury, arthritis or something else, it’s crucial that you address the root issue in order to ease your symptoms.
Wear a Knee Brace
In some cases, a knee brace can help stabilize and heal your joint. For instance, if you have an effusion due to a ligament injury, you may benefit from a wrap, according to a January 2022 StatPearls article.
Talk to your doctor before trying a brace or wrap, though, to make sure it's the right approach for how to get fluid off your knee.
Consider Over-the-Counter Medications
Over-the-counter nonsteroidal anti-inflammatory drugs like ibuprofen (Advil, Motrin) or naproxen (Aleve) may also help relieve the pain in your knee, especially if it's the result of an injury or arthritis, according to the Cleveland Clinic.
If over-the-counter medications are ineffective, ask your doctor about prescription medications. If your knee effusion is due to rheumatoid arthritis or gout, your doctor may prescribe medicine specific to these conditions, per the Cleveland Clinic. Similarly, an effusion caused by septic arthritis or an infection may require antibiotics.
Drain the Fluid
In certain cases, your doctor may recommend removing the excess fluid in your knee.
So, what is the best way to drain fluid from your knee? Through a needle inserted into the joint (a procedure called arthrocentesis), according to the Mayo Clinic. This can help reduce swelling and may also help determine the cause of the effusion, as your doctor will likely send a sample of the fluid to the lab for analysis.
Is It Safe to Try and Drain Fluid Off Your Knee Yourself?
Short answer: No, it is not safe to try draining water on the knee yourself. That's because using unsterilized or used needles can potentially transmit infections, per the FDA.
Indeed, a joint arthrocentesis should only be performed by a doctor.
Try Healing Exercises
Another potential method for how to get rid of fluid in your knee is through physical therapy exercises, according to the Mayo Clinic. Your doctor may recommend this treatment if your effusion is the result of an injury and you need to rebuild strength and mobility in the area.
So, what exercises can you do for water on the knee? Well, that ultimately depends on the type of injury you have. Talk to your physical therapist to get a customized set of knee exercises to reduce inflammation and fluid buildup.
Is Walking Good for Fluid on the Knee?
In general, no, according to the Cleveland Clinic. Typically, rest is best when it comes to healing a joint effusion, so try to avoid overusing or putting weight on the affected knee.
That said, exercising regularly — including activities like walking — can be a helpful way to manage arthritis once the effusion has healed, according to a September 2018 study in the Annals of the Rheumatic Diseases.
Massage Your Knee
Massage can be an effective way to relieve pain and inflammation from osteoarthritis-related knee trouble, according to an October 2020 review in Medicine. It may also help to get rid of fluid on the knee.
How to massage fluid out of your knee depends on the severity and cause of the effusion, so follow your doctor or physical therapist's instructions for the best, safest technique.
- Mayo Clinic: "Swollen Knee"
- Cleveland Clinic: "Joint Effusion (Swollen Joint)"
- StatPearls: "Knee Effusion"
- Annals of the Rheumatic Diseases: "2018 EULAR recommendations for physical activity in people with inflammatory arthritis and osteoarthritis"
- Medicine: "Effectiveness and safety of massage for knee osteoarthritis"
- FDA: "Safely Using Sharps (Needles and Syringes) at Home, at Work and on Travel"
Was this article helpful?
150 Characters Max
Thank you for sharing!
Thank you for your feedback!
Is this an emergency? If you are experiencing serious medical symptoms, please see the National Library of Medicine’s list of signs you need emergency medical attention or call 911.