Sleep disorders are common among the general population and can generate health problems such as insomnia and anxiety. In addition to standard drugs and psychological interventions, there are different complementary plant-based therapies used to treat insomnia and anxiety. This review aimed to find and examine the most recent research on the use of herbal medicines for treating anxiety and insomnia as compiled from clinical trials, as well as to assess the safety and efficacy of these medicines and to elucidate their possible mechanisms of action. The process entailed a search of PubMed, Scopus, and the Cochrane Library databases from 2010 to 2020. The search terms included “sleep disorder”, “insomnia”, “sedative”, “hypnotic”, “anxiety”, “anxiolytic”, and “clinical trial”, combined with the search terms “herbs” and “medicinal plants”, in addition to individual herbal medicines by both their common and scientific names. This updated review, which focuses mainly on clinical trials, includes research on 23 medicinal plants and their combinations. Essential oils and their associations have also been reviewed. The efficacy of medicinal plants depends on treatment duration, types of study subjects, administration route, and treatment method. More clinical trials with an adequate, standardized design are necessary, as are more preclinical studies to continue studying the mechanisms of action. As a result of our work, we can conclude that the 3 plants with the most potential are valerian, passionflower, and ashwagandha, with the combination of valerian with hops and passionflower giving the best results in the clinical tests.
A number of medicinal plants are traditionally endowed with anxiolytic or sedative properties and, in the context of this revue, both indications are considered since the former may induce a mood conducive to the latter. For any sleep-inducing drug to be effective, a tranquil ambience needs to be established a priori. Thus, physical ailments (i.e. pain), factors interfering with sleep (i.e. noise), psychological conditions causing stress, psychiatric illnesses (i.e. depression) and other drugs that interfere with sleep (i.e. caffeine) need to be controlled, if possible. Kava-kava is a well-established hypnotic drug, with a rapid onset of effect, adequate duration of action and minimal morning after-effects. However, reports of serious hepatotoxicity with this preparation have led to it being banned in most countries worldwide. On the other hand, side-effects with valerian would appear to be bland indeed. However, it’s slow onset of effect (2-3 weeks) renders it unsuitable for short-term use (i.e. ‘jet-lag’), but it does have profound beneficial effects on sleep architecture (augments deep sleep) that may make it particularly suitable for long-term use and for the elderly. In a personal trial (not double-blind) in stress-induced insomnia, both kava and valerian improved sleep and the ill-effects of stress, and the combination of the two was even more effective for the control of insomnia. Aromatherapy (lavender, chamomile, Ylang-Ylang) would appear to improve sleep, but how practical a form of treatment this may be remains to be determined. The only other plant drug that may have some effect on sleep is melissa, but reports are too scanty to form any opinion about this. Based on animal experiments, passion flower (passiflora) may have a sedative action, but the sedative action of hops has not been investigated in any detail.
Research in the area of herbal psychopharmacology has increased markedly over the past decades. To date however, a comprehensive review of herbal antidepressant, anxiolytic and hypnotic psychopharmacology and applications in depression, anxiety and insomnia has been absent. A search of MEDLINE (PubMed), CINAHL, PsycINFO, and the Cochrane Library databases was conducted (up to February 21st 2011) on commonly used psychotropic herbal medicines. A review of the literature was conducted to ascertain mechanisms of action of these botanicals, in addition to a systematic review of controlled clinical trials for treatment of mood, anxiety and sleep disorders, which are common comorbid psychiatric disorders. Specific emphasis was given to emerging phytomedicines. Analysis of evidence levels was conducted, as were effect sizes (Cohen’s d) where data were available. Results provided evidence of a range of neurochemical, endocrinological, and epigenetic effects for 21 individual phytomedicines, which are detailed in this paper. Sixty six controlled studies were located involving eleven phytomedicines. Several of these provide a high level of evidence, such as Hypericum perforatum for major depression, and Piper methysticum for anxiety disorders. Several human clinical trials provide preliminary positive evidence of antidepressant effects (Echium amoenum, Crocus sativus, and Rhodiola rosea) and anxiolytic activity (Matricaria recutita, Ginkgo biloba, Passiflora incanata, E. amoenum, and Scutellaria lateriflora).
Herbs for Anxiety
Chamomile (Matricaria recutita)
Plant Part Used: Flowers, dried. These flowers are white and yellow and look like beautiful little daisies. Native to Europe and Asia.
Therapeutic Activity for Mood: Improves relaxation and relieves stress, reduces anxiety, promotes sleep and relieves insomnia.
Indicated for: Anxiety, restlessness, mild sleep concerns, GI upset, stress headaches.
Research Shows: Chamomile interacts with the GABA-system, decreases the stress hormone Cortisol.
Potential Allergy: Though very rare, allergic reactions have been reported to Chamomile. Since it’s in the Daisy (Asteracea) family, people with severe allergies to ragweed, asters, and chrysanthemums should avoid Chamomile (1-5).
Most people have tried Chamomile as a tea and enjoy its sweet and floral smell and relaxing effects. A favorite herb around the world, Chamomile is especially known to be gentle and safe for very young children, even babies. On the Greek Isle of Crete, right after a baby is born, Mom’s breasts are washed with Chamomile before the baby first nurses. When visitors come, they ask if the baby has drunk the Chamomile yet, as it’s a sign that she is healthy and ready to be a part of the community. In Central and South America, Chamomile is traditionally given to babies for a range of ailments, including colic, teething, and sleep concerns – all of which tend to show up as irritation and restlessness (ie anxiety). I usually recommend breastmilk only for a baby under 6 months old, but a breastfeeding mom looking to soothe a fussy baby can take Chamomile and the baby will get some benefit along with mom. In older kids, Chamomile is great for an upset stomach or diarrhea from nervousness, stress headaches, and trouble calming down for bedtime (1-5).
Passionflower (Passiflora incarnata)
Plant Part Used: A flowering vine sporting gorgeous purple flowers. Dried or fresh leaves and flowers used. Native to the Southeastern United States.
Therapeutic Activity for Mood: Improves relaxation and relieves stress, reduces anxiety, promotes sleep and relieves insomnia, anti-depressant.
Indicated for: Anxiety, insomnia, depression, nervous headaches, ADHD, palpitations, exhaustion with muscle pain.
Research Shows: Interacts with the GABA-system, MAO activity (1-4, 6).
Passionflower is commonly used to treat anxiety and mild-moderate sleep concerns, as well as depression. It is especially useful for sleeplessness associated with stress where circular thinking prevents the brain from shutting off (1). It can be used in kids who have restlessness or hyperactivity, stress headaches, and a racing heart. It is commonly used in teenagers with these concerns.
Uses of Passionflower:
Tea: Brew 1-4 cups in the morning and sip throughout the day. Mix with other nervine herbs, such as Chamomile, Lemon Balm, and Milky Oats, adding a natural sweetener if needed. Drink before bedtime for a sedative benefit, also for stress-related headaches and restlessness.
Passionflower tincture: Can be dosed 1-3 times per day or as needed.
Proven Health Benefits of Ashwagandha
Ashwagandha is one of the most important herbs in Ayurveda, which is a traditional form of alternative medicine based on Indian principles of natural healing.
People have used ashwagandha for thousands of years to relieve stress, increase energy levels, and improve concentration .
“Ashwagandha” is Sanskrit for “smell of the horse,” which refers to both the herb’s scent and its potential ability to increase strength (.
Its botanical name is Withania somnifera, and it’s also known by several other names, including “Indian ginseng” and “winter cherry.”
The ashwagandha plant is a small shrub with yellow flowers that’s native to India and Southeast Asia. Extracts or powder from the plant’s root or leaves are used to treat a variety of conditions, including anxiety and fertility issues.
May reduce blood sugar levels
Limited evidence suggests that ashwagandha may have some benefits for people with diabetes or high blood sugar levels.
A review of 24 studies, including 5 clinical studies in people with diabetes, found that treatment with ashwagandha significantly reduced blood sugar, hemoglobin A1c (HbA1c), insulin, blood lipids, and oxidative stress markers .
It’s believed that certain compounds within ashwagandha, including one called withaferin A (WA), have powerful antidiabetic activity and may help stimulate your cells to take in glucose from your bloodstream .
However, research is limited at this time, and more well-designed studies are needed.
Limited evidence suggests that ashwagandha may reduce blood sugar levels through its effects on insulin secretion and cells’ ability to absorb glucose from the bloodstream.
Researchers have found that WA targets inflammatory pathways in the body, including signal molecules called nuclear factor kappa B (NF-κB) and nuclear factor erythroid 2-related factor 2 (Nrf2).
Animal studies have shown that WA may also help reduce levels of inflammatory proteins such as interleukin-10 (IL-10).
There’s some evidence that ashwagandha may help reduce inflammatory markers in humans too.
In one study from 2008, adults experiencing stress took ashwagandha extract for 60 days. As a result, they had significant reductions in C-reactive protein — an inflammatory marker — compared with those who consumed a placebo .
In another study, researchers gave people with COVID-19 an Ayurvedic drug containing 0.5 grams of ashwagandha and other herbs twice per day for 7 days. This reduced participants’ levels of inflammatory markers CRP, IL-6, and TNF-α compared with a placebo .
The treatment formulation also contained:
1 gram of giloy ghanvati (Tinospora cordifolia)
2 grams of swasari ras (a traditional herbo-mineral formulation)
0.5 grams of tulsi ghanvati (Ocimum sanctum)
Even though these findings are promising, research on ashwagandha’s potential effects on inflammation is limited at this time.
Valerian root is the most well-known herb for insomnia. It sedates the higher nerve centers of the cerebrospinal system, promoting sleep without any of the after-effects of narcotics. It can even help people come off of habit-forming sleeping pills. Yet, in rare cases, valerian root can be counterproductive and actually create insomnia and anxiety. Luckily, there are other herbs we can turn to.
When sleepless, try a pinch of nutmeg. Nutmeg has a volatile oil that helps us feel drowsy. While it has been used in small doses by grandmothers since the 1500s, larger doses can be toxic, hallucinogenic, and even deadly. To take nutmeg safely, put 1/8 – ¼ TEASPOON in warm milk before bed.