The products I've seen with the Menthol Crystals usually had this type of a warning... Caution: Not for use if you are pregnant or nursing a baby. Keep away from eyes and sensitive tissue. Consult a physician before using on children. Keep product away from wounds, damaged, broken or irritated skin. Keep out of reach of children.This product is not intended to diagnose, treat, cure or prevent any disease." There has been some problems with use of menthol, eucalyptus and some other essential oils around pets(especially birds). Some labels mention this simply by stating "Not for use on or near pets. Remove pets from room before use. Ventilate well before returning."