Rosemary is likely safe when consumed in amounts found in foods. Rosemary is possibly safe for most people when used as a medicine when taken by mouth, applied to the skin or inhaled as aromatherapy.
However, the undiluted oil is likely unsafe to take by mouth. Taking large amounts of rosemary can cause vomiting, uterine bleeding, kidney irritation, increased sun sensitivity, skin redness and allergic reactions.
Special Precautions & Warnings:
Pregnancy and breast-feeding: Rosemary is possibly unsafe when taken by mouth in medicinal amounts. Rosemary might stimulate menstruation or affect the uterus, causing a miscarriage. Not enough is known about the safety of applying rosemary to the skin during pregnancy. If you are pregnant, it is best to avoid rosemary in amounts larger than food amounts.
If you are breast-feeding, also steer clear of rosemary in medicinal amounts. Not enough is known about what effects it might have on the nursing infant.
Aspirin allergy: Rosemary contains a chemical that is very similar to aspirin. This chemical, known as salicylate, may cause a reaction in people who are allergic to aspirin.
Bleeding disorders: Rosemary might increase the risk of bleeding and bruising in people with bleeding disorders. Use cautiously.
Seizure disorders: Rosemary might make seizure disorders worse. Do not use it.