Rheumatoid arthritis (RA) and Lyme disease are different conditions but share some similar symptoms, which can lead to confusion. RA is a chronic disease that causes inflammation in the joints and can affect other organs. It often appears in middle-aged individuals and is more common in women. Symptoms include joint pain, stiffness, and swelling. Lyme disease, on the other hand, is caused by a bacterial infection from tick bites. It is most common in children, older adults, and people who spend a lot of time outdoors. Symptoms of Lyme disease include fever, headache, fatigue, and a characteristic bull's-eye rash. If left untreated, it can lead to more severe health issues. To differentiate between the two, consult your doctor. They may perform blood tests and refer you to a specialist. Early diagnosis and treatment are crucial for both conditions to prevent complications.