Chamomile
German chamomile: Chamomilla recutita.  Roman chamomile:Chamaemelum nobile 

Chamomile has been used as a medicinal herb for thousands of years, dating back to the ancient Egyptians, Romans and Greeks. It is used to treat to chest colds, sore throats, abscesses, mouth sores, gum inflammation, anxiety, insomnia, psoriasis, acne, eczema, hay fever, inflammation, muscle spasms, menstrual disorders, rheumatic pain, hemorrhoids, minor first-degree burns, stomach cramps, irritable bowel syndrome, indigestion, diarrhea, gas, inflammatory bowel disease, stomach ulcers, chickenpox, diaper rash, and colic. It is available as dried flower heads, tea, liquid extract, essential oil, capsules and topical ointment.

Researchers at the University of Pennsylvania School of Medicine studied the antidepressant properties of chamomile versus a placebo. They noted that anti-anxiety properties had already been observed. Using the Hamilton Depression Rating questionnaire, the researchers observed a significant reduction over time of depression in the participants of the chamomile group vs the placebo group. They concluded that chamomile may provide clinically meaningful antidepressant activity that occurs in addition to the anti-anxiety properties. 

Dosage

Children:

Adults:

References:

Amsterdam, JD., Shults, J., Soeller, I., Mao, JJ., Rockwell, K., Newberg, AB. Chamomile (Matricaria recutita) may provide antidepressant activity in anxious, depressed humans: an exploraty study. Altern Ther Health Med. Sep-Oct 2012;18(5):44-9. Retrieved from: http://www.ncbi.nlm.nih.gov/pubmed/22894890

Ehrlich,  SD. German chamomile. (March 17, 2013). University of Maryland Medical Center.   http://umm.edu/health/medical/altmed/herb/german-chamomile