Comparison of Silybum marianum (L.) Gaertn. with fluoxetine in the treatment of Obsessive-Compulsive Disorder Mehdi Sayyah ⁎, Hatam Boostani, Siroos Pakseresht, Alireza Malayeri Jundishapoor University of Medical Sciences, Ahwaz, Iran abstract article info Article history: Received 5 September 2009 Received in revised form 17 December 2009 Accepted 17 December 2009 Available online 24 December 2009 Keywords: Obsessive–Compulsive Disorder Silybum marianum Yale–Brown Scale Obsessive-Compulsive Disorder (OCD) is a common neuropsychiatric condition. Although a variety of pharmaceutical agents is available for the treatment of OCD, psychiatrists often find that many patients cannot tolerate the side effects of these medications; do not respond properly to the treatment; or the medications lose their effectiveness after a period of treatment. Herbal medicine can be a solution to some of these problems. In fact many herbs with psychotropic effects exist which can have fewer side effects. They can provide an alternative treatment or be used to enhance the effectiveness of conventional anti-obsessive and compulsive symptoms. Silybum marianum (L.) Gaertn. is a well-known medicinal plant with a long history of usage in Iran. This plant is reported to be safe on humans. Our objective in this study was to compare the efficacy of the extract of S. marianum (L.) with fluoxetine in the treatment of OCD. The study was an 8-week pilot double-blind randomized trial. Thirty five adult outpatients who met the DSM-IV-TR criteria for OCD based on the structured clinical interview participated in the trial. The minimum score of Yale–Brown Scale for OCD was 21 for all patients. In this double-blind and randomized trial, patients were randomly assigned to receive either capsule of the extract (600 mg/day) or fluoxetine (30 mg/day) for 8 weeks. The results showed no significant difference between the extract and fluoxetine in the treatment of OCD. There was also no significant difference between the two groups in terms of observed side effects. © 2009 Elsevier Inc. All rights reserved. 1. Introduction Silybum marianum (L.) Gaertn. is a medicinal plant which belongs to the Compositae family, commonly known as Milk Thistle, or St. Mary's Thistle. The plant and its extract are reported to possess hepatoprotective, antioxidant (Morazzoni and Bombardelli, 1995), anticancer (Zi et al., 1997), anti-inflammatory (De La Puerta, 1996), and anti-diabetic (Maghrani et al., 2004) properties. It contains flavonolignan Silymarin, which is an important bioactive substance having anticancer, anti-inflammatory, antioxidant, immune modula- tor (Katiyar, 2005), sedative and anti-depressant (Anjaneyulu et al., 2003; Sayyah et al., 2009) effects. It is native to the Mediterranean regions and is grown in southern Europe (Karen et al., 2005), North Africa and in the Alborz Mountains, and Khuzestan and Azerbaijan provinces of Iran (Ramezani et al., 2008). Silymarin, a mixture of flavanolignans extracted from the seeds of S. marianum, is composed primarily of silibin, silidianin, and silichristin and is considered the major active constituent of S. marianum (Karen et al., 2005). Other components include tyramine, histamine, essential oils, lipids, carbohydrates, alkaloids, saponins, mucilages, organic acid, vitamins C, E, and K, and other flavonoids such as quercetin, taxifolin, and dehydrokaempferol 2, and 3. In addition, Milk Thistle seeds contain betaine (a precursor of S-adenosylmethionine and a potential hepatoprotective substance) and essential fatty acids (Karen et al., 2005). The medicinal usages of Milk Thistle have long been recorded in the history. Theophrastus (c. 371–287 BC), a Greek philosopher and successor to Aristotle, frequently referred to Milk Thistle as Pternix and considered medicinal values for it (Morazzoni and Bombardelli, 1995). Pliny the Elder (23–79 C.E.) and Dioscorides (40–90 C.E.) described this plant and its medicinal uses (Luper, 1998). By the 16th century, Milk Thistle had become a favored medication for hepato- biliary diseases (Schuppan et al., 1999). In 1652, Nicholas Culpeper, a preeminent English herbalist, wrote the book “The English Physician” in which he described Milk Thistle as an excellent remedy for obstructions of the liver and the spleen (Saller et al., 2001). Milk Thistle was brought to the Americas by early European colonists. Since late 20th century, the Eclectics, a group of herbalists, have been using Milk Thistle extracts for treatment of liver, spleen, kidney, and menstrual disorders (Zuber et al., 2002). OCD is a heterogeneous disorder of unknown etiology, character- ized by the presence of upsetting and persistent worries and images or impulses which are experienced as intrusive and senseless (obsessions) and/or excessive repetitive behaviors (compulsions) performed in response to these obsessions, or according to rigid rules (American Psychiatric Association, 2000). Progress in Neuro-Psychopharmacology & Biological Psychiatry 34 (2010) 362–365 Abbreviations: OCD, Obsessive–Compulsive Disorder; Y-BOCS, Yale–Brown Scale. ⁎ Corresponding author. Imam General Hospital, Azadegan Avenue, Ahwaz, Iran. Tel.: +98 611 2222114; fax: +98 611 3367571. E-mail address: sayah_bargard@Hotmail.com (M. Sayyah). 0278-5846/$ – see front matter © 2009 Elsevier Inc. All rights reserved. doi:10.1016/j.pnpbp.2009.12.016 Contents lists available at ScienceDirect Progress in Neuro-Psychopharmacology & Biological Psychiatry journal homepage: www.elsevier.com/locate/pnp