Some people use black seed or black seed oil for treating disorders of the digestive tract, including constipation, diarrhea, hemorrhoids and colic, according to WebMD. Other uses include treatment of respiratory conditions such as flu, bronchitis, cough, allergies and asthma.
Proponents of black seed use it for lowering cholesterol and blood pressure, boosting the immune system, and treating cancer, reports WebMD. Women sometimes use it for increasing milk flow when breastfeeding or to cause menstruation to start. Cancer patients taking cisplatin, a chemotherapy drug, sometimes take black seed oil to relieve side effects caused by the drug. In this instance, patients take it with a combination of saffron, vitamin E and cysteine.