Sir my father has oral cancer. His surgery was done by Dr sultan Pradhan in Mumbai. He is undergoing chemo radiation treatment in Dharamshala hospital, Delhi. His WBC count is 4010, so in order to boost immunity and wbc count can we give him Astragalus. Also, what should be the dose, form in which it should be given and where can we find the herb in its natural form. He does not have any allergies, he only has hyper tension problem and no other issues. Or else what should be done to increase his wbc count. Thank you