WBC spike after Nuelasta/Fulphila

Your RBC and platelets will be unaffected by the Neulasta and falling is expected because they are negatively impacted by the chemotherapeutic agents. You may see a kind of up and then down result like a drop, then a bit of recovery before the next infusion, then another drop ultimately trending in a continually lower net result. This is pretty normal and not super alarming, but watch your hemoglobin and be aware of the signs that it is too low - lethargy, dizziness, shortness of breath. That threshold is different for everybody so don't get too attached to a number, rather check how you feel. Be sure to report any of those to your MO asap if you feel them. Make sure you are ingesting enough protein - even though I didn't like the texture I did try to eat more red meat and other sources of protein in the two weeks prior to the next infusion after the GI distress calmed down immediately after chemo and Herceptin. I did experience spikes from Neulasta, above the range, and that is also not unusual. These meds create a stimulated manufacture of WBC in order to protect you from opportunistic infection, but you may just be a super responder with a more robust than usual reaction. Sometimes you can also have an infection whose WBC response is masked by the drug, so also pay attention to any other symptoms like congestion, coughing, etc., and let your MO know if you have those. Sometimes administering an antibiotic is necessary to potentially treat infection that is simultaneous. If that is the case I would not expect for you to see this after each infusion. Wishing you the best.