Understanding Potential BTK Inhibitor Side Effects
- BTK inhibitors are effective oral treatments for CLL but commonly cause early digestive issues, easier bruising/bleeding, and occasional heart rhythm changes.
- High blood pressure can develop months into therapy, making ongoing monitoring essential, as this side effect is often overlooked.
- Most side effects are manageable or improve over time, and patients who struggle with one BTK inhibitor may be able to switch to another.
- “That’s the beauty of having more than one drug available,” Dr. Jacqueline Barrientos, a blood cancer experts at Mount Sinai Medical Center in Miami Beach, tells SurvivorNet.
Dr. Jacqueline Barrientos, Chief of Hematologic Malignancies at Mount Sinai Medical Center in Miami Beach, tells SurvivorNet that many of these common side effects, while important to monitor for, are manageable.
Read More- Stomach issues (nausea, vomiting, diarrhea)
- Easier bruising and bleeding
- High blood pressure
- Joint pain
GI-related effects that are worse at the start of treatment are a recognized feature of BTK inhibitors like ibrutinib and its newer counterparts, acalabrutinib and zanubrutinib.
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Managing Side Effects
There are interventions your medical team may try if you’re experiencing uncomfortable or potentially dangerous side effects. Keeping your doctors informed is key.
BTK inhibitors interfere with normal platelet function, which can make patients bruise or bleed more easily. Something as small as a cut finger may take longer to stop bleeding.
The drugs have been linked to abnormal heart rhythms, most often atrial fibrillation. This is uncommon, but doctors take it seriously.
If you begin to experience side effects, it’s important to stick to your treatment plan and never stop your BTK inhibitor on your own. Always call your oncologist first if you have any procedure scheduled that you worry may interfere with your treatment plan, even a routine one like a dental extraction or skin biopsy.
An immediate call to your doctor is warranted if you experience potentially serious side effects, like:
- A rapid or irregular heartbeat
- Shortness of breath
- Chest pain
WATCH: Looking at Blood Counts for CLL Prognosis
Long-Term Side Effects
One of the trickier side effects is high blood pressure, which often doesn’t appear right away.
“After six months or seven months on the drug, they need to make sure that the blood pressure doesn’t go higher, because these drugs can cause it,” Dr. Barrientos tells SurvivorNet. “That’s not usually well recognized. It took us many years to recognize that side effect.”
Doctors generally aim to keep blood pressure under 130 (systolic) to reduce the risk of complications.
If blood pressure is hard to control even with two or three medications, an oncologist may consider switching to a different BTK inhibitor with a lower risk of this side effect.
Some patients also develop joint pain that can flare up periodically. Since there are now multiple BTK inhibitors on the market, patients who don’t tolerate one drug well may be able to switch to another in the same class that causes less of this particular side effect.
Most side effects of BTK inhibitors are manageable, and many improve with time. Bruising, bleeding risk, blood pressure changes, and heart rhythm issues are the ones to watch for and report promptly. Never adjust or stop your medication without talking to your care team first.
Questions To Ask Your Doctor
- What is the best way to contact you if I am experiencing side effects?
- How will I be monitored during treatment?
- What happens if my cancer continues to progress?
- What are the next steps if my side effects become too much to manage?
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