Thanks for asking at Healthcare Magic. I read your question and I understand your concern. Chalk contains lead and arsenic. Both are toxic to humans especially pregnant ladies, nursing mothers and also these have effects on fetuses. It causes impaired growth and neurodevelopmental abnormalities. Besides these inhibits absorption of iron and zinc and lead to iron deficiency anemia. Also these can cause mechanical blockage of intestines. Chalk is mostly used by diabetic people for reducing nausea and vomiting due to diabetes and by pregnant women to decrease morning sickness. All that she need is to bring diabetes in control. Take prokinetic like itopride or domeperidone. Do regular aerobic excersize. Also have mental relaxation excersizes. Hope it helps best. Don t forget to rate this answer and close the discussion at Healthcare Magic. Take your best care and of your friend. Regards Dr Ejaz