Nwobodo N.N. and Offiah R.O. The use of medicinal plants in the treatment of mental disorders: an overview. International j phytopharmacy, 2017. 7(3): 18-22.

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Nwobodo N.N. and Offiah R.O. / International Journal of Phytopharmacy May-Jun 2017; Vol. 7 (3): pp. 18-22. 18
IJPP | Volume 7 | Issue 3 | 2017 www.ssjournals.com
International Journal of Phytopharmacy Review Article
ISSN: 2277-2928 (Online)
Journal DOI: https://doi.org/10.7439/ijpp
The use of medicinal plants in the treatment of mental
disorders: An overview
Nwobodo N.N.*1 and Offiah R.O.2
1Division of Clinical Pharmacology and Translational Medicine, Faculty of Clinical Medicine, Enugu State University of
Science and Technology (ESUT), Enugu, Nigeria.
2Department of Pharmacology and Therapeutics, College of Medicine, Enugu State University of Science and Technology
(ESUT), Enugu, Nigeria.
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*Correspondence Info:
Nwobodo N.N.
Division of Clinical Pharmacology and Translational Medicine,
Faculty of Clinical Medicine, Enugu State University of Science and
Technology (ESUT), Enugu, Nigeria.
*Article History:
Received: 04/07/2017
Revised: 09/07/2017
Accepted: 09/07/2017
DOI: https://doi.org/10.7439/ijpp.v7i3.4264
Abstract
It has been known from the ancient times, spanning hundreds of years of recorded and unrecorded history, that
people have used different methods and procedures in treatment of different psychiatric disorders and very often these were
medicinal preparations from plants. Numerous scientific discoveries and advent of industrial age gave a big boost to drug
development and significantly improved quality of life for psychiatric patients during the last century. Nevertheless, after
huge success, joy and relief, evidence has shown that quest for natural medicines faced a lot of disappointment, leading to a
poor attitude that resulted to some natural drugs unnecessarily thrown out. On the other hand, there are a huge number of
patients that use natural medicinal plants in self-treatment of different psychiatric disorders. It is reported that herbal
medicines are used in treating a broad range of psychiatric disorders including anxiety, depression, obsessive-compulsive,
affective, bipolar maniac-depressive, psychotic, phobic and somatoform disorders. Currently, there is insufficient clinical
evidence for the use of many herbal medicines in psychiatric disorders. Significant and urgent research are required to
address current issues in herbal psychotherapy such as herbal safety, future areas of application, the relationship of herbal
medicine with pharmaceuticals and the potential prescriptive integration of phytomedicines with synthetic psychotropic
medicines.
Keywords: Drug-herb interaction, herbal medicine, medicinal plants, mental disorder, phytomedicine and phytotherapy.
1. Introduction
According to the World Health Organization[1],
mental health is „a state of well-being in which the
individual realizes his or her own abilities, can cope with
the normal stresses of life, can work productively and
fruitfully, and is able to make meaningful contribution to
his or her community‟. Mental health can also be defined as
a state of mind in which an individual can effectively utilize
his or her capacities by displaying psychological resilience
in making personal and social adjustments to fit the
dynamic environment within which he or she co-exists with
other persons [2]. It also represents one‟s ability to adapt to
internal and external environmental stressors. Successful
adaptation to a range of demands is manifested in thoughts,
emotions and behaviours that are in congruence with age,
local and cultural norms or expectations [3]. To be mentally
unhealthy signifies a psychological state that results in
behavioural anomalies that affect daily functioning. Mental
health problems may be associated with genetics,
environmental stressors, psychological factors, brain
defects, substance abuse, amongst other factors [4]. The
prevalence of mental illness is linked to the many socio-
economic problems which may be regarded as precipitating
factors [5].
Persons with mental health problems have been
perceived with a sense of suspicion for many decades[6],
just as mental health problems have been associated with
several misconceptions. The most common misconceptions

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about mental health illness are damaging and pervasive.
Some of these misconceptions are that people with mental
illness are dangerous and violent; that mental illness is the
same as mental retardation; that mental health problems are
as a result of poor parenting; that it is impossible to recover
from mental illness; that persons with mental health
problems cannot work; that lack of personal hygiene and
physical unattractiveness are indicators of mental illness
and unintelligent persons are prone to mental illness. Most
of these misconceptions have however been disproved as
being unfounded [7-9] and can thus be regarded as largely
being unscientific or unverifiable. Societies across the
world have different explanatory perspectives as it relates to
the nature, causes and interventions for mental health
problems [10]. In this light, cultural misconceptions
significantly affect the level of stigma that is attached to
mental illness as well as the social support likely to be
received [11]. A country like Nigeria in West Africa, for
instance, is a multi-ethnic state with a myriad of cultures,
traditions, customs and beliefs at the center of its
worldview. All of these aspects or dimensions of the
Nigerian State influence, amongst many matters, the
perception of mental health problems. Specifically, the
belief in the supernatural is reinforced in the daily
cosmology of many Nigerians. Health is viewed by many as
being underpinned by supernatural dimensions [12,13].
Supernatural beings or powers (God, gods, good and evil
spirits, witches) coupled with their activities [14] are
believed to be sources of mental health problems as well as
part of the cultural asset that is usually mobilized to cure
mental health problems. Many Nigerian cultures attribute
mental illness to angered ancestors and spirit possession or
a punishment meted by a retributive god [15].
2. Prospects of Medicinal Plants in the
Treatment of Mental Disorders
Medicinal plants have great prospects in healthcare
delivery worldwide. These prospects have more impact in
developing countries where 70-80% of the population rely
on traditional medicine for primary healthcare [16]. It is
reported that 25% of prescribed drugs in conventional
healthcare were derived from their ethnomedicinal use in
traditional medicine [16]. Medicinal plants still provide
hope for discovery of new drugs for the resistant diseases
and those that were not treated by conventional prescription
drugs. The symptoms of mental illness often are effectively
controlled through herbal medication and/or psychotherapy,
and may even go into remission. For some people, the
illness continues to cause periodic episodes that require
treatment. Consequently, some people with mental illness
will need no support, others may need only occasional
support and still others may require more substantial,
ongoing support to maintain their productivity [17].
3. Nature of Mental Disorders
Mental illness is a term that describes a broad
range of mental and emotional conditions, and is different
from other covered mental impairments such as mental
retardation, organic brain damage and learning disabilities.
The term „psychiatric disability‟ is used when mental illness
significantly interferes with the performance of major life
activities, such as learning, working and communicating,
among others [17]. The most common forms of mental
illness are anxiety disorders, mood disorders and
schizophreniac disorders.
3.1 Anxiety Disorders
The most common group of mental illnesses are
anxiety disorders which is often characterized by severe
fear or anxiety associated with particular objects and
situations. Anxiety disorders may occur in any of the
following ways:
 Panic disorder – the sudden onset of paralyzing terror or
impending doom with symptoms that closely resemble a
heart attack.
 Phobias – excessive fear of particular objects (simple
phobias), situations that expose a person to the possible
judgment of others (social phobias), or situations where
escape might be difficult (agoraphobia).
 Obsessive-compulsive disorder – persistent distressing
thoughts (obsessions) that a person attempts to alleviate
by performing repetitive, intentional acts (compulsions)
such as hand washing.
 Post-traumatic stress disorder (PTSD) – a psychological
syndrome characterized by specific symptoms that result
from exposure to terrifying, life-threatening trauma such
as an act of violence, war or a natural disaster[17].
3.2 Mood Disorders
These involve changes in mood, usually involving
either depression or mania (elation). Mood disorders are
also known as affective disorders.
 Major depression – an extreme or prolonged episode of
sadness in which a person loses interest or pleasure in
previously enjoyed activities.
 Bipolar disorder (also referred to as maniac-depressive
illness) – alternating episodes of mania (“highs”) and
depression (“lows”).
 Dysthymia – continuous low-grade symptoms of major
depression and anxiety.
 Seasonal affective disorder (SAD) – a form of major
depression that occurs in the fall or winter and may be
related to shortened periods of daylight [17].

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3.3 Schizophreniac Disorders
Research has not yet determined whether
schizophrenia is a single disorder or a group of related
illnesses. The illness is highly complex, and few
generalizations hold true for all people diagnosed with
schizophreniac disorders. However, most people initially
develop the symptoms between the ages of 15 and 25.
Typically, the illness is characterized by thoughts that seem
fragmented and difficulty in processing information.
Symptoms of schizophreniac disorders are categorized as
either “negative” or “positive”. Negative symptoms include
social isolation or withdrawal, loss of motivation and a flat
or inappropriate affect (mood or disposition). Positive
symptoms include hallucinations, delusions and thought
disorders [17].
4. Commonly Used Medicinal Plants for the
Treatment of Mental Disorders
The following herbs are known to have a
traditional history of promoting mental health:
4.1 Mulungu Bark (Erythrina mulungu)
The indigenous people of South and Central
America have used mulungu for centuries to calm nerves,
improve mood and aid sleep. Erythravine, one of mulungu‟s
active alkaloids, may also help reduce anxiety and protect
brain function [18]. Flavonoids present in this herb are
known antioxidants and have been shown to support
cardiovascular health and a healthier brain [19].
4.2 Bacopa (Bacopa monnieri)
Commonly known as Brahmi, Ayurvedic medicine
uses bacopa to improve memory, reduce stress and support
cognitive function. Researchers observed that cortisol, the
body‟s stress hormone, decreased in study participants who
took bacopa compared with those taking a placebo [20].
Additional research indicates it may support the physical
health of brain cells and offer some protection against brain
aging and age-related diseases such as Alzheimer‟s disease
[21].
4.3 Mucuna pruriens
Mucuna contains L-dopa, a biochemical precursor
to several neurotransmitters. One of those neurotransmitters
is dopamine, and increasing dopamine levels may improve
brain function and support memory. This effect probably
contributes to Mucuna‟s popularity as an anti-aging herb.
Antioxidant properties linked to Mucuna also discourage
inflammation and suggest protective effects for neurons
[22].
4.4 Rhodiola Rosea
This traditional medicinal herb contains two
powerful natural compounds that have been proven to play
a role in brain health. Salidroside is one of these
compounds and is known as a potent antioxidant. Rosin is
the other, and this compound appears to reduce
inflammation of neural cells, possibly protecting against
neurotoxicity [23]. The results of one Swedish study
showed that both of these compounds reduced fatigue,
improved mood and lowered stress hormones [24]. This
may lead to better mental performance and a more positive
response to stress and anxiety.
4.5 Ziziphus jujube
Also known as “sour date” Ziziphus jujube is one
of the many herbs that may support mental health while
encouraging a good night‟s rest. Day-to-day activities can
be draining on energy levels, not to mention mental
strength. The plant‟s saponins have demonstrated sedative
effects on animal models, possibly supporting relaxation
[25].
4.6 Passiflora incarnata (Passionflower)
This traditional herbal sedative has been used as a
sleep aid for years. Passionflower also appears to help
relieve anxiety, a major cause of sleep disturbance for many
individuals. Without a good night‟s sleep, mental acuity
becomes compromised and memory also degrades. Initial
studies indicate consuming low doses of passionflower in a
tea helps healthy adults achieve better sleep [26].
4.7 Scutellaria lateriflora (Skullcap)
Native to North America, this plant has a history
of use for calming nerves, easing stress, lifting the mood
and aiding sleep. Research suggests it possesses mood
enhancing effects and its antioxidant properties may
provide significant protection for the brain against the
damaging effects of inflammation [27,28].
4.8 Kava
Kava is used traditionally to relieve stress, anxiety
and insomnia. Kava contains compounds known as
kavalactones. These compounds offer non-opiate
alternatives against anxiety. Some studies indicate
kavalactones is as effective as certain orthodox drugs [29].
4.9 Saffron
Saffron, also known as Crocus sativus, does more
than add color and flavor to food. It has a long history of
use for mood disorders, stress and anxiety. Studies have
also found it as effective as antidepressants for lifting mood
and relieving anxiety, significantly out performing placebo
in clinical trials [30].
4.10 Ficus ingens (Miquel) Miquel
Ficus ingens which belongs to the Moraceae
family, is one of the many medicinal plants with long
historical use in traditional medical practices [31,32]. A
research reported that the methanolic stem bark extracts of
Ficus ingens (Miquel) Miquel prolonged the duration of
diazepam induced sleep time in mice, which is suggestive
of sedative property of the methanolic stem bark extracts of

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Ficus ingens (Miquel) Miquel using animal model[31,32].
The prolongation of diazepam-induced sleeping time may
be attributed to an action on the central mechanism
involved in the regulation of sleep [31].
5. Drug-Herb Interactions Particularly with
Orthodox Drugs for Treating Mental
Disorders
The use of herbal supplements has a long history,
dating back thousands of years. Examples of important
orthodox medicines extracted from botanicals include
reserpine, morphine, penicillin and vinca alkaloids[33].
Herbal products can frequently have drug interactions with
prescription medications. Herbal interactions with
prescriptions can interfere with how the drug may be
broken down in the body, enhance side effects of
prescription medications or block the intended therapeutic
effect of a drug [34].
Ginkgo biloba extract, advertised as improving
cognitive functioning, has been reported to cause
spontaneous bleeding, and it may interact with
anticoagulants and antiplatelet agents. St. John's wort,
promoted as a treatment for depression, may have
monoamine oxidase–inhibiting effects or may cause
increased levels of serotonin, dopamine and norepinephrine.
Ephedrine-containing herbal products have been associated
with adverse cardiovascular events, seizures and even
death. Ginseng, widely used for its purported physical and
mental effects, is generally well tolerated, but it has been
implicated as a cause of decreased response to warfarin[35].
6. Conclusion
In conclusion, the preference and utilisation of
natural medicine derived from plant sources in the
treatment of mental disorders over orthodox medicine can
never be over-emphasized. A significant number of herbal
extracts derived from medicinal plants have been shown to
be effective in treating mental disorders in the traditional
setting. There is, therefore, a dire need to encourage the
recommendation and use of these medicinal plants as they
are relatively safe, efficacious and readily available;
particularly in the depressed economic and poor resource
setting prevalent in developing countries.
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