Disease-modifying antirheumatic drugs (DMARDs) are a type of immunomodulatory or immunosuppressive therapy. It is used to treat arthritis (joint inflammation and discomfort) in conditions such as rheumatoid arthritis (RA), psoriatic arthritis (PsA), and ankylosing spondylitis. It is also used in other connective tissue disorders such as systemic lupus erythematosus (SLE), systemic sclerosis (SSc), Sjogren syndrome (SS), inflammatory bowel disease, and several kinds of malignancies.
Types of DMARDs
DMARDs are classified as conventional DMARDS and biologic DMARDS.
i. Conventional DMARDs:Â These are older medications like methotrexate, leflunomide, hydroxychloroquine, azathioprine and sulfasalazine. They are often used as first-line treatments.
ii. Biologic DMARDs:Â These newer medications are typically prescribed if conventional DMARDs don't work well enough. They are highly specific and target particular immune pathways. Examples include infliximab, adalimumab, etanercept, rituximab, abatacept, tocilizumab, and tofacitinib. They belong to various groups, such as monoclonal antibodies, receptor fusions, or small molecule inhibitors like Janus kinase (JAK) inhibitors.
For example, Olumiant 4mg tablet contains an active component such as Baricitinib. They are Janus kinase (JAK) inhibitors. This medicine usually blocks JAK1 and JAK2 enzymes. These enzymes are important for sending signals that lead to inflammation in the body. By blocking them, Olumiant reduces inflammation and helps control conditions like rheumatoid arthritis.
DMARDs in RA
DMARDs are the best-known treatment for Rheumatoid arthritis. Though many medications can be used in treating rheumatoid arthritis (RA), methotrexate is commonly used as the initial treatment. RA treatment is very complex. Several factors influence decision-making, including disease activity and severity, the presence of other health conditions, and patient preferences such as cost, method of administration, and monitoring frequency.
RA treatment may involve either a single medication (monotherapy) or a combination of medications (combination therapy). Research has revealed that combination therapy, such as pairing a biologic DMARD with a conventional DMARD like methotrexate, is often more effective than either medication alone, as shown in various randomised controlled trials.
Treatment objectives typically aim to achieve either remission or low disease activity while halting joint damage progression. Initiating therapy early after diagnosis is beneficial in preventing radiographic progression, much of which tends to occur within the initial months of the disease.
Mechanism of action of DMARDs
DMARDs in RA ensure the proper functioning of the body's immune system.
In autoimmune diseases like RA, the body's immune system works badly, attacking the body's cells instead of foreign cells that invade.
1. They target specific pathways in the body's immune system.
2. They act on individual proteins within the immune system.
3. They inhibit inflammation through various mechanismsÂ
Therapeutic effect DMARDs bring in RA patients
1. Decrease joint pain and inflammation.
2. Help reduce joint damage and prevent bone erosion.
3. Slow the speed and progression of disease.
4. Preserve joint function.
Side effects of DMARD
Hydroxychloroquine:
Common: Rash, diarrhea.
Rare but Significant: Retinopathy/maculopathy (higher with cumulative dose), anemia, leukopenia, myopathy, cardiomyopathy.
Methotrexate, Leflunomide, Sulfasalazine:
Common side effects are Gastrointestinal distress (nausea, abdominal pain, diarrhea), rash/allergic reaction, bone marrow suppression, hepatotoxicity, and a higher risk of infections.
Biologic DMARDs:
Serious side effects include increased risk of common and serious infections (bacterial, fungal, viral).
Pros and ConsÂ
DMARDs are widely used, with about 83% of people worldwide using them. The withdrawal of COX-2 inhibitors due to heart-related side effects and the short-term relief provided by steroids pushed the development of newer DMARDs. Currently, non-biological DMARDs like methotrexate, sulfasalazine, hydroxychloroquine, and azathioprine help with pain relief and slowing down disease progression. Biological DMARDs such as tocilizumab, adalimumab, infliximab, golimumab, and abatacept are even more effective and have fewer side effects than non-biological DMARDs. Still, they are less accessible to patients due to their higher cost.
Conclusion
It is important to understand that DMARDs are complex drugs with potential side effects, so it's best to have them prescribed by a specialist such as a rheumatologist, gastroenterologist, or dermatologist. Regular follow-ups will help assess the effectiveness of the DMARDs and detect any side effects. As a team, including you, your healthcare provider, pharmacist, and nurse, we can ensure the best possible outcomes for your treatment while minimizing any risks or complications.