Much of the original research on the use of the commonly known herbal medicine to treat stress, anxiety and depression was carried out in the last ten years. More recent research focuses on the potential of new herbal remedies, but there are fewer studies. Most of the studies use a combination of several herbs or compare different substances.
A naturopathy study in 2009 showed that 300mg of Ashwagandha twice a day combined with dietary counseling, breathing relaxation techniques and a standard general multivitamin showed reduced anxiety improved mental health, concentration, reduced fatigue, better vitality, social functioning and improved quality of life, compared to a control group.
Bacopa (Bacopa monnieri)
A Lab study carried out in 2010 compared the effects of Bacopa monnieri and Panax quniquefolium (American ginseng) on the symptoms of mixed anxiety-depressive disorder. Both substances were effective as an anti-anxiety as well as an anti-depressant.
Chamomile (Matricaria recutitatia)
Studies have shown the anxiolytic effects of chamomile and a recent publication has shown that it is also effective in patients with an overlap of anxiety and depression. A study of the data from a 2009 trial revealed that chamomile proved to have clinically meaningful antidepressant activity with its observed anxiolytic activity.
Hawthorn (Crataegus monogyna Jacq)
A lab study carried out in 2010 investigated the effects of hawthorn fruit extracts on the central nervous system. Hawthorn is traditionally used for its sedative and pain killer action. Results showed a reduction of stress and nervousness and confirmed the traditional use to treat stress, nervousness, sleep disorders, and pain control.
Kava (Piper methysticum)
Kava is a traditional remedy that has been used in the Polynesian islands of the Pacific as a sedative. However, Kava remains a controversial remedy due to its potential liver toxicity. The EU banned the import of Kava based medicines and remedies in 2002 and sale of kava plants is regulated in Switzerland, France and Holland. Poland has a total ban on kava products and in the UK it is a criminal offence to sell, supply or import kava medicinal products. Patient QI looked at the most recent Cochrane review on Kava, which concluded the following: Systematic literature searches were conducted to assess the evidence for or against the effectiveness of kava extract for treating anxiety. Twenty-two potentially relevant double-blind, placebo-controlled RCTs were identified. Twelve trials met the inclusion criteria. The meta-analysis of seven trials suggests a significant treatment effect for the total score on the Hamilton Anxiety Scale in favour of kava extract. Few adverse events were reported in the reviewed trials, which were all mild, transient and infrequent. These data imply that, compared with placebo, kava extract might be an effective symptomatic treatment for anxiety although, at present, the size of the effect seems to be small. Rigorous trials with large sample sizes are needed to clarify the existing uncertainties. Particularly long-term safety studies of kava are needed.
Lemon Balm (Melissa officinalis)
A study carried out in 2006, looked at the effect of a combination of Melissa officinalis (lemon balm) and Valeriana officinalis (valerian) on people who were placed under stress in a lab situation. Results showed a 600 mg dose of the combination reduced anxiety but that the highest dose (1800 mg) showed a very slight increase in anxiety.
Another study carried out in Germany used the monitoring of electrical activity in the brain to measure the state of relaxation in volunteers. One group of volunteers were given a lozenge containing lavender oil, extracts from hops, lemon balm and oats; a second group were given placebo. The changes in electrical activity that were observed in the treatment group showed a clear picture of a state of relaxation and regeneration.
Magnolia (Magnolia officinalis) and Phellodendron (Phellodendron amurense)
Patient QI found a recent study published in Aug 2013 that assessed the effects of Magnolia and Phellodendron bark supplements on psychological mood state and salivary cortisol levels in women with moderate stress. After 4 weeks of supplements the treatment group had 18 per cent lower salivary cortisol, 11% overall lower stress, 13% reduced tension, 20% reduction in depression, 42% reduction in anger, 31% reduction in fatigue and 27% reduction in confusion compared to a placebo control group. The treatment group also had high overall scores of mood state and vigor.
Passion flower (Passiflora incanata)
Passion flower has a long traditional use as a sedative in Europe and is a component of many combination herbal remedies. The most recent study that Patient QI found using Passion flower as a single remedy was published in Feb 2012. The study looked at the effects of a preoperative oral dose of Passion flower before patients had a spinal anesthesia and results were compared with a placebo group. Results showed that the treated group had a much lower increase in state anxiety before the operation than the placebo control group.
Skullcap (Scutellaria lateriflora)
Skullcap is a traditional remedy for stress and anxiety. A study published in 2013 tested the effects of 350mg of skullcap three times a day for two weeks in a test group of mildly anxious people and compared results to a placebo group. Results showed a significant decrease in mood disturbance and enhanced overall mood with no reduction to energy levels in the test group compared to the placebo group.
Patient QI found an excellent study published in Dec 2012 by a Spanish group that investigated the use of Valerian as a supportive treatment for patients on a Benzodiazepine withdrawal program. Patients who had been daily users of benzodiazepines for more than 6 months had their dosage reduced by 25% every 2-4 weeks and were given the option of supportive therapy of Hydroxyzine or Valerian. At the end of the six month program 80.4% had discontinued benzodiazepines completely.
A study published in 2011 evaluated the use of Valeriana Officinalis for the treatment of Obsessive-Compulsive disorder (OCD). The group of patients that were given 765mg of Valerian extract per day for 8 weeks showed significant improvement compared to the placebo treated group.
A lab study carried out in Korea investigated the effects of herbal extracts of Gynostemma pentaphyllum on stress-induced anxiety disorders. Treatment with the herbal extract reduced the symptoms of stress and protected the dopamine and serotonin levels as well as reducing levels of corticosterone.
A laboratory based study carried out in Korea evaluated whether wild ginseng (WG) could reduce anxiety and depression following morphine withdrawal. Results showed that the Ginseng reduced anxiety and depression and also suppressed Corticoid Releasing hormone.