Side Effects of Gugulipid

Does gugulipid have any side effects, such as changing the color of the stool? My father is taking it and his stool color changed. What other effects does it have?

Prominent herbalist Kerry Bone, in his book "Clinical Applications of Ayurvedic and Chinese Herbs" (Phytotherapy Press, Australia), states that Guggul (Commiphora mukul) are: anti-cholesterol, anti-platelet, anti-inflammatory and anti-obesity. In studies to try to understand how guggul lowers, cholesterol, it was found to have a thyroid stimulating effect. Therefore, this herb should not be taken in hyperthyroid situations or with blood thinning medication, unless advised by a medical practitioner. It is also contraindicated in pregnancy and breastfeeding.
Bone notes one study where side effects were observed in a few patients: headache, mild nausea, hiccup and burping.
I have no reports or information on change of stool colour with gugulipids.
For more information on guggul, please go to our web site at www.richters.com, and choose "Q&A". Then enter "guggul" for the search.