Cyclosporine: What It Is, How It Works, and What You Need to Know

When your body starts attacking its own tissues—or worse, rejects a new organ—you need something to calm it down. That’s where cyclosporine, a potent immunosuppressant drug that blocks T-cell activation to prevent organ rejection and autoimmune flare-ups. Also known as CsA, it’s been a lifeline for transplant patients since the 1980s and remains a cornerstone in treating conditions like psoriasis, rheumatoid arthritis, and severe eczema. Unlike broad-spectrum steroids, cyclosporine targets specific immune cells, making it more precise—but not without serious trade-offs.

What makes cyclosporine tricky is how it interacts with your body. It doesn’t just suppress the immune system—it can also strain your kidneys, raise blood pressure, and increase your risk of infections and even certain cancers. Many people take it for years after a transplant, but that long-term use means regular blood tests, strict dosing schedules, and watching for signs like swelling in the hands or feet, which can signal toxicity. It’s not a drug you start and forget. You need to know how it fits with other meds—like antibiotics or antifungals—that can spike its levels dangerously. And if you’re on it for an autoimmune condition, you’re likely weighing the relief it brings against the daily risk of catching a cold that turns into pneumonia.

It’s not the only option anymore. Newer biologics and JAK inhibitors are replacing cyclosporine in some cases because they’re safer long-term. But for many, especially in places where newer drugs are too expensive or hard to get, cyclosporine is still the go-to. That’s why knowing how to talk to your doctor about side effects, when to test your blood levels, and how to avoid dangerous interactions matters more than ever. The posts below cover exactly that: how to manage cyclosporine safely, what to do if you notice swelling or unusual fatigue, how to handle missed doses, and how it stacks up against other immunosuppressants. You’ll also find real advice on sharing your full medication list with your care team—because mixing cyclosporine with the wrong supplement or OTC painkiller can be life-threatening. This isn’t theoretical. It’s what people are living with every day.