This story represents a composite of common IBD experiences and is presented to help readers feel less alone in their journey.

The Moment Everything Changed

The IV line was already in my arm, the familiar pre-medication cocktail of Benadryl and Tylenol coursing through my veins, when I felt it start. First came the tightness in my chest—subtle at first, like someone had wrapped a gentle band around my ribs. Then my skin began to flush, a creeping warmth that spread from my neck down my arms. By the time the nurse noticed my blood pressure dropping on the monitor, I was struggling to breathe.

“Stop the infusion,” she called out, her voice cutting through the fog of my panic. The infliximab—my miracle drug, the medication that had given me my life back after two years of devastating Crohn’s disease—was trying to kill me.

As medical staff rushed around me, administering epinephrine and steroids to reverse what was clearly an anaphylactic reaction, one thought kept running through my mind: What happens now? This wasn’t just any medication I was allergic to. This was the only treatment that had ever worked for my severe Crohn’s disease.

When Your Miracle Drug Betrays You

Six months earlier, infliximab had been my salvation. After trying mesalamine, prednisone, azathioprine, and methotrexate with little success, my gastroenterologist had recommended the TNF-alpha inhibitor as our next step. The results were nothing short of miraculous. Within weeks, my debilitating abdominal pain subsided, my energy returned, and for the first time in years, I could eat without fear.

The first few infusions went smoothly. I’d arrive at the infusion center, chat with the nurses I’d grown to know, and spend three hours reading or working on my laptop while the medication dripped into my system. It became routine—almost boring, which felt like a blessing after the chaos Crohn’s had brought to my life.

But bodies change, and immune systems can develop new sensitivities. My allergist later explained that what happened to me occurs in about 10-15% of people receiving infliximab. My immune system had developed antibodies against the medication, essentially treating this life-saving drug as a foreign invader that needed to be eliminated.

The scariest part wasn’t just the physical reaction—it was the realization that I might lose the only treatment that had ever controlled my Crohn’s disease. My gastroenterologist was honest: we could try switching to a different biologic, but there was no guarantee it would work as well. The thought of returning to the constant pain, the unpredictable flares, and the bathroom urgency that had defined my life before infliximab filled me with dread.

Navigating the Impossible Choice

The weeks following my allergic reaction were some of the most challenging of my IBD journey. Without infliximab, my symptoms began creeping back. The familiar cramping returned, along with the fatigue and joint pain that had become my unwelcome companions. My gastroenterologist started me on a high dose of prednisone to buy us time while we figured out our next steps, but we both knew this wasn’t a sustainable solution.

That’s when she mentioned something I’d never heard of: drug desensitization protocols. “There’s a procedure,” she explained during one of our urgent follow-up appointments, “where we can potentially help your body tolerate infliximab again. It’s not simple, and it’s not without risks, but for patients like you who’ve had such a good response to a particular medication, it might be worth exploring.”

She referred me to an allergist who specialized in drug desensitization procedures. Dr. Martinez explained that desensitization is different from simply treating allergic reactions. “We’re essentially retraining your immune system,” she said. “By exposing you to very small, gradually increasing doses of infliximab in a controlled hospital setting, we can often help your body develop tolerance to the medication again.”

The process sounded both promising and terrifying. I’d need to be admitted to the hospital for the procedure, which could take anywhere from 4-6 hours. I’d be connected to continuous monitoring equipment, with emergency medications at the ready in case I had another severe reaction. There was no guarantee it would work, and there was always the risk that I could have an even worse allergic reaction during the process.

But the alternative—losing the medication that had given me my life back—felt worse than the risk.

The Day That Changed Everything

Three weeks later, I found myself in a hospital bed, connected to more monitors than I could count. The desensitization protocol Dr. Martinez had designed for me involved twelve different steps, starting with an incredibly diluted dose of infliximab—about 1/10,000th of my normal dose—and gradually increasing the concentration and volume every 15-20 minutes.

The first few steps were nerve-wracking but uneventful. I felt nothing as the tiny amounts of medication entered my system. Dr. Martinez and the specialized nursing team monitored my vital signs, watching for any signs of reaction: changes in blood pressure, heart rate, oxygen saturation, or skin flushing.

Around step six, when we’d reached about 1/100th of my normal dose, I started to feel that familiar tightness in my chest. My heart rate increased slightly, and I felt a wave of anxiety wash over me. “This is normal,” Dr. Martinez reassured me, adjusting my pre-medications and slowing down the infusion rate. “Your body is recognizing the medication, but we’re giving it time to adapt.”

The next few hours were a careful dance between pushing forward and pulling back. At step nine, my blood pressure dropped slightly, so we paused the infusion for thirty minutes and gave me additional antihistamines. At step eleven, I developed mild hives on my arms, which responded quickly to additional Benadryl.

But we made it through. By the end of the day, I had successfully received my full dose of infliximab—the same dose that had sent me into anaphylaxis just a month earlier. More importantly, I had tolerated it. The desensitization protocol had worked.

Learning to Live with Vigilance

Successfully completing the desensitization procedure was just the beginning of a new chapter in my IBD management. Dr. Martinez explained that maintaining tolerance to infliximab would require ongoing vigilance and some significant changes to my treatment routine.

First, I could never miss an infusion. The tolerance we’d built up during desensitization could be lost if there were gaps in treatment longer than the normal 8-week interval. This meant planning vacations, work trips, and family events around my infusion schedule became more critical than ever.

Second, every infusion now required enhanced monitoring. Instead of the relaxed atmosphere I’d grown accustomed to in the regular infusion center, I now received my treatments in a specialized unit equipped for immediate emergency response. The nursing staff was trained in managing allergic reactions, and emergency medications were always within reach.

My pre-medication protocol also became more intensive. In addition to the standard Benadryl and Tylenol, I now receive a higher dose of corticosteroids before each infusion, and the infusion itself runs more slowly—taking about four hours instead of the previous three.

The psychological adjustment was perhaps the most challenging part. Every infusion brought back memories of that terrifying allergic reaction. I found myself hyperaware of every sensation in my body during treatments—was that chest tightness normal, or was it starting again? The anxiety was real and persistent, and I eventually started working with a therapist who specialized in medical trauma to help me develop coping strategies.

But the results speak for themselves. Eighteen months after my desensitization procedure, I’m still in remission. My Crohn’s disease remains well-controlled, and I’ve been able to maintain the quality of life that infliximab originally gave me. The enhanced monitoring and slower infusions are small prices to pay for keeping my miracle drug.

Hope for Others Walking This Path

If you’re facing a similar situation—if your body has turned against a medication that’s been working for your IBD—please know that you’re not alone, and you may have more options than you realize. Drug desensitization protocols aren’t available everywhere, and they’re not appropriate for every type of allergic reaction, but for the right candidates, they can be genuinely life-changing.

The key is working with specialists who understand both IBD and drug allergies. Not every allergist is familiar with desensitization procedures, and not every gastroenterologist knows when to refer patients for these specialized treatments. Don’t be afraid to seek out second opinions or ask for referrals to academic medical centers where these procedures are more commonly performed.

It’s also important to understand the difference between true allergic reactions and infusion reactions. Many people experience mild symptoms during biologic infusions—things like headaches, fatigue, or mild nausea—that aren’t true allergies and don’t require desensitization. A qualified allergist can help determine whether your reactions warrant this more intensive approach.

Most importantly, don’t lose hope. The field of drug desensitization is advancing rapidly, with new protocols being developed for different medications and different types of reactions. What seemed impossible just a few years ago is becoming routine care at many medical centers.

Living with IBD means constantly adapting to new challenges, and developing drug allergies is certainly one of the more frightening complications we can face. But as I’ve learned, even when our bodies seem to be working against us, there are often solutions we haven’t considered yet. Sometimes the path forward requires more courage, more monitoring, and more complexity than we’d like, but the destination—a life well-lived despite IBD—remains within reach.