Side Effects of Chamomile

Roman chamomile seems safe for most people when taken by mouth as medicine and in foods. In large amounts, it can cause vomiting. It can also cause an allergic reaction in people sensitive to ragweed, marigolds, daisies or similar herbs.
The essential oil of Roman chamomile also seems to be safe when inhaled or applied to the skin.

Special Precautions & Warnings:

Pregnancy and breast-feeding: Roman chamomile is likely unsafe when taken by mouth in medicinal amounts during pregnancy. Roman chamomile is believed to cause miscarriages. Not enough is known about the safety of applying it to the skin during pregnancy. Avoid using Roman chamomile if you are pregnant.

It is also best to avoid Roman chamomile if you are breast-feeding. Not enough is known about how it might affect the nursing infant.

Allergy to ragweed and related plants: Roman chamomile may cause an allergic reaction in people who are sensitive to the Asteraceae/Compositae family. Members of this family include ragweed, chrysanthemums, marigolds, daisies, and many others. If you have allergies, be sure to check with your healthcare provider before taking Roman chamomile.

(Source: www.webmd.com)