Indigo is a flowering plant that has been used as a dye. The root has been used as an oil or cream to ease swelling from skin and joint problems like psoriasis. It can also be taken as a pill, powder, or extract. Indigo can also be made into a tea.Dosages
There are no advised doses for indigo.
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Certain species of indigo are not safe. Only use indigo that is from a reliable source. It is likely safe for most adults to use indigo on the skin. It may be safe to take indigo orally for a short time, but it may raise blood pressure. Not enough studies have been done to say whether it is safe to use for a long period.B1-B3
Talk to your doctor about any supplements or therapy you would like to use. Some can interfere with treatment or make conditions worse, such as:
A1. Deng S, May BH, et al. Plant extracts for the topical management of psoriasis: a systematic review and meta-analysis. Br J Dermatol. 2013 Oct;169(4):769-782.
A2. Lin YK, Chang YC, et al. A Chinese herb, indigo naturalis, extracted in oil (Lindioil) used topically to treat psoriatic nails: a randomized clinical trial. JAMA Dermatol. 2015 Jun;151(6):672-674.
A3. Farahnik B, Sharma D, et al. Topical botanical agents for the treatment of psoriasis: a systematic review. Am J Clin Dermatol. 2017 Aug;18(4):451-468.
A4. Cheng HM, Wu YC, et al. Clinical efficacy and IL-17 targeting mechanism of Indigo naturalis as a topical agent in moderate psoriasis. BMC Complement Altern Med. 2017 Sep 2;17(1):439.
B1. Matsuno Y, Hirano A, et al. Possible association of phlebitis-induced colitis with indigo naturalis. Gastroenterology. 2018 Aug;155(2):576-577.
B2. Nishio M, Hirooka K, et al. Pulmonary arterial hypertension associated with the chinese herb indigo naturalis for ulcerative colitis: it may be reversible. Gastroenterology. 2018 Aug;155(2):577-578.
B3. Kondo S, Araki T, et al. Colitis with wall thickening and edematous changes during oral administration of the powdered form of Qing-dai in patients with ulcerative colitis: a report of two cases. Clin J Gastroenterol. 2018 Aug;11(4):268-272.
C. Ulcerative Colitis
C1. Naganuma M, Sugimoto S, et al. Efficacy of indigo naturalis in a multicenter randomized controlled trial of patients with ulcerative colitis. Gastroenterology. 2018;154(4):935-947.
Last reviewed February 2020 by EBSCO NAT Review Board
Eric Hurwitz, DC
Last Updated: 5/27/2020