Interaction between warfarin and astaxanthin: A case report.

This report explains the potential interaction between warfarin and astaxanthin in a 69-year-old Thai woman with history of ischemic stroke. Before taking astaxanthin, the patient used constant doses of warfarin, atenolol, digoxin, aspirin, omeprazole, and simvastatin concomitantly for 17 days without any signs and symptoms of adverse events. One day after astaxanthin was supplemented to her treatment regimen, ecchymosis was found on the right side of her groin and thigh. On the next day, area of ecchymosis was larger. International normalized ratio (INR) values increased from 1.4 to 10.38. Warfarin and astaxanthin were withheld and vitamin K was given. Two days later, INR reduced to 1.43 and symptoms of ecchymosis were better. Causality assessment of adverse drug reaction indicated a probable relationship between bleeding symptoms and astaxanthin supplementation. Counseling the patients and caregivers as well as monitoring for potential interactions with dietary supplements should be considered as an active process in order to prevent negative outcomes to patients undergoing warfarin therapy. .

Efficacy and safety of mirtazapine in fibromyalgia syndrome patients: a randomized placebo-controlled pilot study.

BACKGROUND: Data from an open-label trial suggest that mirtazapine might prove useful in treatment of fibromyalgia syndrome (FMS). OBJECTIVE: To obtain preliminary efficacy data of mirtazapine for estimation of sample size requirements for a Phase 2 clinical trial in FMS. METHODS: This 13-week randomized controlled trial compared the effects of mirtazapine 15 mg/day, mirtazapine 30 mg/day, and placebo in 40 patients with FMS. The primary outcomes were change in Pain Visual Analog Scale (PVAS) and proportion of pain responders (≥30% PVAS reduction). Secondary outcomes included scores from the Jenkins Sleep Scale (JSS), Patient Global Impression of Change (PGIC), Fibromyalgia Impact Questionnaire (FIQ), Hamilton Depression Rating Scale (HAM-D), Patient Global Assessment, and self-reported adverse events. RESULTS: Significant within-group PVAS reductions from baseline were observed in all 3 groups, with the greatest improvement in the mirtazapine 30-mg group (p < 0.005); between-group difference was not significant. The proportion of pain responders did not meet significance criteria (66.67% for mirtazapine 30 mg, 50% for mirtazapine 15 mg, 41.67% for placebo). Significant within-group improvement in JSS scores was seen for mirtazapine 30 mg (p < 0.01) and mirtazapine 15 mg (p < 0.05). Between-group comparison achieved significance for JSS item 3, waking several times per night (p < 0.05). On the PGIC, 72.73% felt better with both mirtazapine dosages compared with 50% for placebo. Within-group FIQ responses indicated improvement in only mirtazapine-treated groups, whereas within-group improvement for HAM-D and Patient Global Assessment was observed in all groups. Based on our findings, the sample size requirement (80% power, 5% type I error) should be 83 per group to detect PVAS change difference between mirtazapine 30 mg and placebo. Common mirtazapine-related adverse events were increased appetite and weight gain. CONCLUSIONS: Patients with FMS taking mirtazapine exhibited within-group significant improvement in most of the measured outcomes. Between-group analysis was predictably compromised by the small sample size. Mirtazapine was well tolerated. Further study with a larger sample size is likely to be useful.