Find Information About:

Drugs & Supplements

Get information and reviews on prescription drugs, over-the-counter medications, vitamins, and supplements. Search by name or medical condition.

Pill Identifier

Pill Identifier

Having trouble identifying your pills?

Enter the shape, color, or imprint of your prescription or OTC drug. Our pill identification tool will display pictures that you can compare to your pill.

Get Started

My Medicine

Save your medicine, check interactions, sign up for FDA alerts, create family profiles and more.

Get Started

WebMD Health Experts and Community

Talk to health experts and other people like you in WebMD's Communities. It's a safe forum where you can create or participate in support groups and discussions about health topics that interest you.

  • Second Opinion

    Second Opinion

    Read expert perspectives on popular health topics.

  • Community


    Connect with people like you, and get expert guidance on living a healthy life.

Got a health question? Get answers provided by leading organizations, doctors, and experts.

Get Answers

Sign up to receive WebMD's award-winning content delivered to your inbox.

Sign Up

Osteoarthritis Health Center

Font Size

Injectable Medications for Knee Osteoarthritis

Hyaluronic Acid

Most of the fluid in a healthy knee is hyaluronic acid, Altman says. But when you have knee OA, the hyaluronic acid in your knee thins. Your doctor can inject more hyaluronic acid into your knee to boost the supply.

Studies have shown that hyaluronic acid injections may help more than pain-relief medications for some people with OA. Other studies have shown they may improve symptoms as well as corticosteroid injections do. If you're considering hyaluronic acid injections, keep these in mind:

It’s often not the first approach. Your doctor may suggest hyaluronic acid if:

  • Your symptoms aren't improved by pain-relief medications or non-drug treatments such as heat or ice.
  • You can't take pain relievers such as Advil or Motrin (ibuprofen), Aleve (naproxen sodium), or Tylenol (acetaminophen).
  • A steroid shot doesn’t help enough, or you or your doctor are concerned about its side-effects.

It may work in different ways. After an injection, hyaluronic acid helps cushion and lubricate the moving parts within your knee, Altman says. This effect is fairly short-lived. But the treatment seems to also provide more long-term benefit by relieving pain and inflammation.

You may need more than one injection. Five versions of hyaluronic acid injections are available in the U.S. Some types require only one injection. Others require up to five injections, usually within a five-week period. If needed, you can get another shot after six months, Altman says.

Platelet-Rich Plasma: Can It Help OA?

Another treatment getting attention is platelet-rich plasma (PRP). This requires drawing a sample of your blood and processing it to create a fluid that contains a higher-than-normal amount of platelets, tiny disks that help clot the blood. The doctor then injects the fluid back into your injured area.

The platelets in your blood contain natural chemicals that help heal injuries. Doctors have been treating other problems – like tendon damage – for more than a decade with PRP.

However, experts still know little about whether it works for knee osteoarthritis. 

1 | 2
Reviewed on April 17, 2014

Today on WebMD

elderly hands
Even with arthritis pain.
woman exercising
Here are 7 easy tips.
acupuncture needles in woman's back
How it helps arthritis, migraines, and dental pain.
chronic pain
Get personalized tips to reduce discomfort.
Keep Joints Healthy
Chronic Pain Healthcheck
close up of man with gut
man knee support
woman with cold compress
Man doing tai chi
hand gripping green rubber ball
person walking with assistance