Understanding Osteoarthritis: Part 1

There are about 100 different types of arthritis. Osteoarthritis, also known as degenerative joint disease, is the most common form of arthritis. It affects more than 20 million people in the United States and is the leading cause of disability in older adults. Osteoarthritis is a chronic disease, which means that it often lasts a lifetime. There are a number of ways to effectively treat osteoarthritis, however, allowing most people with the disease to live a comfortable and fulfilling life.

What Is Osteoarthritis?

Osteoarthritis is a disease that gradually damages the cartilage of the joints. Joints are places in the body where two bones come together. Cartilage is the slippery material that covers the ends of bones, providing a smooth surface for ease of movement and a cushion to absorb impact

during physical movement, such as walking. In osteoarthritis, the cartilage breaks down, allowing bones to rub against one another (Figure 1). The joints that are usually affected by osteoarthritis include the knees, hips, feet, and back. It can cause pain and stiffness in the joints and limit movement. Inflammation in the joint is not a major part of osteoarthritis. Rheumatoid arthritis, often confused with osteoarthritis, is an inflammatory disease affecting the lining of the joints, making them tender, warm, and red. Patients with rheumatoid arthritis can develop severe deformities. Also unlike osteoarthritis, rheumatoid arthritis is a systemic disease, meaning it can affect the whole body and cause damage to organs.

What Causes Osteoarthritis?

In the past, osteoarthritis was considered to be a normal part of aging. Although older people are at higher risk for osteoarthritis, there are many factors that can work together to cause osteoarthritis:

• Genetics
• Obesity
• Work-related joint injuries
• Sports-related joint injuries

What Are the Symptoms of Osteoarthritis?

Pain is the main reason that patients with this disease see their doctor or pharmacist. The pain associated with osteoarthritis is not usually caused by inflammation in the joints. Instead,

pain is caused by multiple sources, including bones rubbing against one another due to cartilage damage (Figure 2). Some people with osteoarthritis may have occasional inflammation or ?flare-ups? as the condition becomes more severe. This differentiation is important in deciding the appropriate treatment for osteoarthritis. In addition, joint aches and pains may come from other causes besides osteoarthritis, so it is important that you see your doctor before treating yourself with medications.

How Is Osteoarthritis Diagnosed?

Physicians diagnose osteoarthritis based on the patient?s history of symptoms and physical examination. X-rays may be used to confirm the diagnosis. Some patients show signs of osteoarthritis on an X-ray but may not experience symptoms such as pain.

Treating Osteoarthritis with Nonprescription Drugs

Acetaminophen Guidelines from the American College of Rheuma-tology recommend acetaminophen (such as Tylenol) as first-line drug treatment for pain associated with osteoarthritis. It has efficacy similar to nonprescription nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen, yet it is much safer than NSAIDs. For maximum relief of pain, experts recommend taking up to 4 g (4,000 mg) over 24 hours on an as-needed basis. The dose of acetaminophen in Tylenol? Arthritis Pain, used as directed, provides the appropriate amount of medication for maximum efficacy. Although aceta-minophen is very safe at recommended doses, it has a potential to cause liver problems in certain patients when they take more than the recommended dose. Therefore, as with all of your medications, it is important to read all warning labels before taking this medication.

NSAIDs

NSAIDs are generally recommended as a second-line therapy?when pain relief with acetaminophen is inadequate. Many prescription NSAIDs, such as Celebrex and Naprosyn, and nonprescription NSAIDs are available on the market. Aspirin (eg, Bayer, St. Joseph), ibuprofen (Advil, Motrin), naproxen (Aleve), and keto-profen (Orudis KT) are just some of the nonprescription drugs available. Prescription NSAIDs, most commonly used to treat inflammatory conditions, are also effective in alleviating pain associated with osteoarthritis. Nonpre-scription doses of NSAIDs have weak and sometimes no anti-inflammatory effect, so they are often used to reduce pain. However, both prescription and nonpre-scription NSAIDs carry a higher risk for side effects, such as stomach irritation. More severe side effects, such as ulcers and bleeding in the stomach and esophagus, can occur in certain at-risk patients, including:

• Elderly patients
• Patients with a history of ulcers
• Patients who smoke
• Patients taking a corticosteroid

It is important to know that more than one NSAID should not be taken at the same time, because this will increase the risk of side effects without providing additional pain relief. You may ask your doctor or pharmacist, however, about using acetaminophen and an NSAID together for additional pain relief.

What Do I Need to Know Before Taking Nonprescription Medications?

Several drugs are effective in treating pain associated with osteoarthritis, but a number of factors need to be considered before taking medications. Ask your doctor or pharmacist the following questions before taking a nonprescription medication for pain:

• Does the pain medication interact with any other drug(s) (nonprescription or prescription) that I am taking?
• Do I have a medical condition that might make taking this medication inadvisable?
• What are the side effects of the drug?

Conclusion

Osteoarthritis is a degenerative joint disorder characterized primarily by pain, but it also causes stiffness and crackling in the affected joints. Inflammation, a major component of rheumatoid arthritis, is not usually associated with osteoarthritis. Acetaminophen (Tylenol) is recommended as first-line treatment for pain associated with osteoarthritis, but ask your pharmacist whether this or any regimen is right for you. Nondrug approaches can also help patients with osteoarthritis. These will be discussed in-depth in next month?s issue of Pharmacy Times.