American skullcap (Scutellaria lateriflora): a study of its effects on mood in healthy volunteers

INTERVENTION: Intervention: organic freeze‐dried Scutellaria lateriflora capsules 350 mg three times daily Placebo control: organic freeze‐dried stinging nettle leaf (Urtica dioica folia) capsules 300 mg three times daily The study will last for 38 days including a 7‐day washout period. Participants will be randomly assigned to receive either freeze‐dried Scutellaria lateriflora test or freeze‐dried Urtica dioica folia placebo three times daily for half of the intervention study duration and then, following a washout period of 1 week, will cross over to receive the other for comparison. In other words, participants will be acting as their own controls. Clinical reporting scales and salivary cortisol measurements will be used to compare anxiety symptoms and quality of life at the beginning, before the end of the first half prior to crossover, and at the end of the clinical study. There have been no reports of toxicity associated with S. lateriflora. To confirm its safety profile, all participants will undergo fingerpick blood extraction for liver function analysis pre‐, intermediate and post‐intervention. CONDITION: Moderate anxiety ; Mental and Behavioural Disorders ; Other anxiety disorders PRIMARY OUTCOME: Reduction in anxiety following 2 weeks' intervention in comparison to placebo control, indicated by a significantly reduced score on the Beck Anxiety Inventory, projected to be at least 10 points (0 ‐ 7 = no anxiety‐minimal anxiety; 8 ‐ 15 = mild anxiety; 16 ‐ 25 = moderate anxiety; 26 ‐ 63 = severe anxiety). SECONDARY OUTCOME: 1. Self‐reported changes in quality of life; 2. Changes in salivary cortisol measurements to indicate a reduction in stress levels; 3. Live blood analysis of liver function by fingerprick blood extraction; ; Sampling and testing for secondary outcome measures will be conducted prior to commencement of the interventional stage of the study in order to take baseline measurements for comparison with subsequent measurements, during the last 2 days of the first half of the intervention prior to a 7‐day washout period and during the last 2 days of the second half of the intervention study following crossover. Pulse and blood pressure will also be assessed at these time‐points as a matter of interest. INCLUSION CRITERIA: Current inclusion criteria as of 24/03/2011: 1. Aged 18 ‐ 75 years, either sex 2. Good general health 3. Males and females 4. Participants will be volunteers and will have given informed consent 5. Agree to undergo a fingerprick blood test for analysis of liver function pre‐, intermediate‐ and post‐intervention Previous INCLUSION CRITERIA: 1. Symptoms of moderate anxiety, indicated by a cut‐off score point for anxiety on the Beck Anxiety Inventory (BAI) between 16 ‐ 25 2. Aged 18 ‐ 75 years, either sex 3. Good general health 4. Males and females 5. Participants will be volunteers and will have given informed consent 6. Agree to undergo a fingerprick blood test for analysis of liver function pre‐, intermediate‐ and post‐intervention