The Activate warning is not listed anywhere on the website or the product fact sheet, only on the outside of the box.
NOTICE: This product contains Rheum palmatum L. (turkey rhubarb root). Read and follow directions carefully. Do not use if you have or develop diarrhea, loose stools, or abdominal pain because turkey rhubarb may worsen these conditions and be harmful to your health. Consult your physician if you have frequent diarrhea or if you are pregnant, nursing, taking medication, or have a medical condition.
CAUTION: Do not exceed recommended dose. This product should be consumed with at least a full glass of liquid. Drinking this product without enough liquid may cause choking. Do not take this product if you have difficulty swallowing. May cause allergic reaction in persons sensitive to inhaled or ingested psyllium.