The dose is soooo small that she should be ok. Dr Yen is lactose intolerant and has no problems. A quick internet search shows no one has had problems. If she has problems she can try taking the pill intravaginally because lactose intolerance is not an allergy but a lack of enzyme to digest it. Without the enzyme then the lactose in the gut causes side effects bc bacteria then digest it causing gas diarrhea etc. If she has milk allergy, she should be fine with medical grade lactose bc the allergy is to a protein and not the lactose.