Most Tepezza side effects resolve within a few weeks after the final infusion, but some, particularly hearing-related problems, can persist for months or potentially become permanent. Because Tepezza has a long half-life of about 20 days, the drug stays active in your body for several weeks after your last dose, which means side effects don’t necessarily stop the moment treatment ends.
How Long Tepezza Stays in Your Body
Tepezza is cleared slowly, with a half-life of 20 days. In practical terms, that means it takes roughly three to four months after your last infusion for the drug to be almost entirely eliminated. Side effects tied directly to the drug’s activity can linger during this washout period, gradually fading as levels drop. This timeline is important context for everything below: even after your eighth and final infusion, the medication is still working (and still capable of causing effects) for weeks.
Side Effects That Typically Resolve Quickly
Infusion Reactions
Reactions during or shortly after an infusion, such as flushing, headache, or nausea, are usually mild to moderate and occur within 1.5 hours of the infusion ending. These are treated on the spot with antihistamines or corticosteroids and generally don’t carry over to the next day. Once you’re done with infusions, this category of side effect is behind you entirely.
Mild Digestive Symptoms
Mild diarrhea and nausea are among the more common side effects during the treatment course. For most people, these symptoms ease as the body adjusts to the medication and resolve once treatment is complete. However, Tepezza can in rare cases trigger inflammatory bowel disease, which causes bloody diarrhea, severe stomach pain, or rectal bleeding. That’s a different situation from ordinary GI discomfort and requires immediate medical attention, as it may not resolve on its own.
Muscle Spasms
About half of patients in one observational study reported new or worsening muscle spasms in their arms and legs during treatment. The good news is that roughly 74% of patients who completed therapy reported their symptoms had resolved by the time they were interviewed, on average about four weeks after the last infusion. The range was one to 12 weeks. So for most people, muscle cramps are a temporary nuisance that clears up within the first couple of months after finishing treatment.
Hearing Problems: The Major Concern
Hearing loss and tinnitus are the side effects that worry patients most, and for good reason. The original clinical trials reported subjective hearing loss in about 10% of patients and described it as reversible. But that reassuring number hasn’t held up well under scrutiny. Subsequent research using actual hearing tests (audiometry) has found ear-related side effects in up to 30% of patients. More importantly, multiple published cases have documented persistent sensorineural hearing loss, typically in the mild to moderate-severe range, with no improvement on hearing tests several months after stopping the drug.
This is the side effect most likely to become permanent. The hearing loss is caused by damage to the inner ear’s sensory structures, and once those cells are harmed, they don’t regenerate easily. Not everyone who experiences hearing changes during Tepezza will have lasting problems, but the earlier claim that hearing loss “resolves without intervention” was not backed by objective audiometric testing, and the real-world picture is less optimistic.
The FDA recommends hearing assessments before, during, and after treatment. If you notice muffled hearing, difficulty following conversations, or ringing in your ears during or after Tepezza, getting a formal hearing test gives you a baseline to track whether things are improving or stable. There is no established timeline for when hearing loss from Tepezza “should” recover. Some patients see partial improvement over months; others do not.
What Long-Term Follow-Up Shows
In the OPTIC trial’s 48-week off-treatment follow-up period, no new safety concerns emerged, including among patients who received additional Tepezza infusions. This is somewhat reassuring: it suggests that for the majority of patients, side effects don’t worsen or appear for the first time long after treatment ends. The main risk window is during the treatment course and the few months immediately following it, as the drug clears your system.
A Realistic Timeline to Expect
Here’s a practical summary of what to expect after your final infusion:
- First 1 to 2 weeks: Infusion-related symptoms (headache, flushing, fatigue) stop entirely. Mild nausea and diarrhea begin to improve.
- Weeks 1 to 12: Muscle spasms fade for most patients, with the majority resolving by about four weeks out.
- Months 1 to 4: The drug is still being cleared from your body. Lingering side effects should continue to gradually improve during this period.
- Beyond 4 months: Any side effect still present at this point, especially hearing loss, is less likely to resolve on its own. This is when a conversation with your doctor about next steps becomes important.
The overall pattern is encouraging for most side effects. Three quarters of patients in post-treatment surveys reported their symptoms had resolved within weeks. Hearing changes are the clear exception, and the one area where you should be proactive about monitoring rather than assuming things will get better with time.