Synovetin OA: Using Radioisotopes to Manage Arthritis

Osteoarthritis (OA) is one of the most common causes of chronic pain in both dogs and cats. It affects the joints, causing inflammation, stiffness, and reduced mobility. Many pets suffer in silence as they age, and while traditional treatments like anti-inflammatories and joint supplements can help, they often fall short in controlling long-term pain and disease progression. Enter Synovetin® OA, a therapy that targets the source of joint inflammation, not just the symptoms.

What Is Synovetin OA?

Synovetin OA is a radiotherapeutic joint injection designed to provide long-lasting relief from osteoarthritis. It works by delivering a small amount of Sn-117m, a radioisotope of tin, directly into the affected joint. The treatment stays localized, emitting low-energy radiation that selectively deactivates overactive synovial macrophages, the inflammatory cells at the root of OA.

Unlike oral medications or systemic injections, Synovetin OA is:

• Targeted: Stays in the joint where it’s injected.
• Long-Lasting: Provides up to one year of relief from a single treatment.
• Minimally Invasive: No ongoing medication schedule; just one outpatient procedure.

How It Works

The lining of an arthritic joint, known as the synovium, becomes inflamed and overproduces substances that degrade cartilage and cause pain. Synovetin OA quiets this process by delivering targeted radioisotopes to:

• Neutralize inflammatory macrophages
• Preserve healthy joint tissue
• Interrupt the cycle of pain and degeneration

This process is known as radiosynoviorthesis (RSO) and has been used safely in human medicine for decades. Synovetin OA adapts this proven concept for veterinary use in dogs and, in select cases, cats, too.

Who Is a Good Candidate?

Synovetin OA is approved for elbow OA in dogs but is used off-label by many veterinarians in hips, knees, and shoulders, and even in cats with chronic joint pain.

Ideal candidates include pets who:

• Have mild to severe OA, especially in one or two joints
• Are not responding well to daily medications or can’t tolerate them
• Need long-term pain relief without the hassle of daily pills
• Show early signs of OA, like lameness, stiffness, or reduced activity

Real Results, Backed by Research

Published studies on this therapy (the first of their kind to track results out to one year) showed

• 92% of dogs with mild to moderate OA showed clinical improvement
• 71% of dogs with severe OA also improved
• Many pets resumed activity within 2-4 weeks post-injection
• Relief lasted 6 to 12 months or more with just one injection

What Is the Treatment Like?

• Your pet receives the injection under sedation or anesthesia.
• There is no hospital stay, and most pets go home the same day.
• A short rest period is recommended, but most pets return to regular activity quickly.
• The treatment is safe and contained within the joint, with minimal radiation exposure to people or other pets.

Part of a Multimodal Approach

At VRA, I use Synovetin OA as part of a comprehensive OA management strategy. It pairs well with:

• Rehabilitation therapy (e.g., underwater treadmill, other exercises)
• Weight management

What About Cost?

Synovetin OA is often comparable in cost to a year’s worth of daily pain medications. Better yet, many pet insurance plans now cover the treatment. And since it may reduce the need for other medications or frequent vet visits, it can be a cost-effective solution over time.

Is It Right for Your Pet?

If your dog or cat has been diagnosed with arthritis or is showing signs like stiffness, limping, difficulty rising, or reduced play, talk to your veterinarian about whether this long-lasting, targeted treatment is an option.

You can also visit ActiveDogNow.com to learn more and find a provider near you.