Several studies have found this is effective against many of the over-growths of bacteria families seen in CFS, unfortunately it also impacts E.Coli which CFSers are low in. This herb was found to be as potent as ciprofloxacin, gentamycin, kanamycin, ofloxacin and cephalexin. This superior performance was reported in another study of 66 herbs.  It has no adverse effects on the growth of the lactic acid-producing bacteria.

Personally, I found that it caused a significant cognitive improvement within days. I was doing a capsule of Mutaflor with it daily.

According to Wikipedia[Wikipedia]:

Haritaki is a rejuvenative, laxative (unripe), astringent (ripe), anthelmintic, nervine, expectorant, tonic, carminative, and appetite stimulant. It is used in people who have leprosy (including skin disorders), anemia, narcosis, piles, chronic, intermittent fever,heart disease, diarrhea, anorexia, cough and excessive secretion of mucus, and a range of other complaints and symptoms. According to the Bhavaprakasha, Haritaki was derived from a drop of nectar from Indra’s cup. Haritaki is used to mitigate Vata and eliminate ama (toxins), indicated by constipation, a thick greyish tongue coating, abdominal pain and distension, foul feces and breath, flatulence, weakness, and a slow pulse. The fresh fruit is dipana and the powdered dried fruit made into a paste and taken with jaggery is malashodhana, removing impurities and wastes from the body. Haritaki is an effective purgative when taken as a powder, but when the whole dried fruit is boiled the resulting decoction is grahi, useful in the treatment of diarrhea and dysentery. The fresh or reconstituted fruit taken before meals stimulates digestion, whereas if taken with meals it increases intelligence, nourishes the senses and purifies the digestive and genitourinary tract. Taken after meals Haritaki treats diseases caused by the aggravation of Vayu, Pitta and Kapha as a result of unwholesome food and drinks. Haritaki is a rasayana to Vata, increasing awareness, and has a nourishing, restorative effect on the central nervous system. Haritaki improves digestion, promotes the absorption of nutrients, and regulates colon function.

Drug interactions are known[Online Herbal].