Transcript Medical herbalism

Medical herbalism
Definition
• Medical herbalism may
be defined as the
practice of using
products in which all
active ingredients are of
herbal origin to treat the
sick. In practice rather
more detail is required.
Definition
• According to the World Health Organization
(WHO) Guidelines, herbal medicines are
considered to be:
Plant-derived materials or products with
therapeutic or other human health benefits which
contain either raw or processed ingredients from
one or more plants.
• In some traditions materials of inorganic or animal
origin may also be present.
Definition
• The European Directive defines a herbal
medicine thus:
A substance or combination of substances
of herbal origin presented for treating or
preventing disease or with a view to making a
medical diagnosis or to restoring, correcting or
modifying physiological functions.
History
• The exact origins of
herbalism are unknown.
Probably it was several
different groups of
prehistoric peoples who
discovered that some
herbs were good to eat,
whereas others had
curative powers.
• Humans also discovered
plants with peculiar, reality
altering, stimulating and
inebriating effects. In
ancient cultures these were
considered to be ‘plants of
the gods’.
History
• The mechanism of action of herbs remained a
mystery for centuries – and in some cases still
remains a mystery. Only the development of
sophisticated techniques of chemical analysis in the
last century has begun to provide some of the
answers.
• The first medical records date from ancient Assyria,
China, Egypt and India.
History
• William Turner was the first person to study plants
scientifically in the sixteenth century. He travelled
widely throughout Europe and grew plants in his
gardens in south-west London (later the Royal
Botanical Gardens, Kew).
History
• At this time the Doctrine of Similars
determined how plants were used.
It was promoted by Paracelsus
(1493–1541). According to this
paradigm every plant acted in
effect as its own definition of its
medical application, resembling
either the part of the body afflicted
or the cause of the affliction.
• Nicholas Culpepper (1616–54) was
an influential proponent of the
Doctrine of Signatures as well as
various astrological theories, by
which herbs were set under the
domination of the sun, moon or
one of the five planets then known.
His herbal, published in 1652, was
extremely successful, being
reprinted many times.
History
• In America Samuel Thomson (1769–1843) used simple
herbs for bodily correction. He was so successful that
opposition from the medical profession was strong and
uncompromising. His fame spread to England where,
thanks to the promotion by a Mr George Lees, the
Thomsonian system was embraced byMr Jesse Boot
when he opened the first of what was to become the UK’s
biggest multiple pharmacy chain, in Goose Gate,
Nottingham in 1872.
• Renewed interest in ‘natural’ medicines has led to a
resurgence of demand for herbal medicines in the last 20
years.
Theory
• Traditionally, the herbalist has recognised four
clear stages when offering treatment for any
particular condition, individualising the
prescription according to holistic methodology to
take account of their patients’ particular needs:
1. Cleansing the body.
2. Mobilising the circulation.
3. Stimulating digestion.
4. Nourishment and repair.
Theory
1. Cleansing the body: removal of toxins and other
noxious influences – real or imagined – that
might cause a physical or mental barrier to
treatment. Diuretics, expectorants and laxatives
are involved here.
2. Mobilising the circulation: traditionally disease
was seen as a ‘cold’ influence on the body and
before any other treatment the body should be
comforted by ‘heating agents’. Hot spices and
pungent medicines (e.g. ginger) and more
gentle warming medicines are available for this
purpose.
Theory
3. Stimulating digestion: inappropriate or too much heat in
the body manifests itself as fevers and inflammatory
conditions. Thus, the so-called ‘cooling medicines’ are
those used to treat these circumstances, leading to
improved digestion. Anti-inflammatories, antiallergics
and sedatives are examples of therapeutic classes of
drugs that fall into this category.
4. Nourishment and repair: in this phase the herbalist
deals with the debility arising from disease in the body.
The term ‘tonic’ covers a wide range of medicines used
to support the body. Examples include hawthorn
(Crataegus oxycanthoides), milk thistle (Silybum
marianus) and St John’s wort (Hypericum perforatum).
Sources of reference
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Materia medica
Repertory
The British Herbal Pharmacopoeia
The American Herbal Pharmacopeia
Sources of reference
• Materia medica: a comprehensive list
detailing the main characteristics and uses
of medicines, e.g. Potter’s Cyclopaedia of
Botanic Drugs
• Repertory: a comprehensive list of medical
conditions with suggested medicines for
treatment, e.g. Herbal Medicine by Miller
and Murray
Sources of reference
• The British Herbal Pharmacopoeia gives
identification and usage information as well as
providing instructions on how medicines should be
prepared and the British Herbal Compendium
provides up-to-date summaries of the available
scientific knowledge on medicinal plants
• The American Herbal Pharmacopeia (www.herbalahp.org) began developing qualitative and
therapeutic monographs in 1994, and intends to
produce 300 monographs on botanicals, including
many of the ayurvedic, Chinese and western herbs
most frequently used in the USA.
General types of medicinal herbs
used
• Practitioners use medicinal plants with:
- powerful actions, e.g. liquid extracts of foxglove and
belladonna, with substantial toxic risk
- intermediate actions, e.g. tinctures of arnica and
khella, with some adverse drug reactions (ADRs)
- gentle actions, e.g. infusions of German camomile
and peppermint with less risk of ADRs.
• In many instances conditions can be treated by
drugs in each of the three groups, e.g. cardiac
disease responds to foxglove in the powerful group,
arnica in the intermediate group and hawthorn in
the gentle group.
Examples of the therapeutic use of
herbal remedies
Active constituents in herbal medicines
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Bitters
The ‘hot’ medicines
Resins
Saponins
Tannins
Volatile oils
Active constituents in herbal medicines
Bitters
• Traditionally these were used extensively to
stimulate appetite (i.e. in the final fourth stage of
the healing process outlined above).
• It is now thought that they will be effective only if a
malnourished state exists.
• The bitter constituents simulate the bitter receptors
in the taste buds at the back of the mouth and give
rise to an increase in the psychic secretion of
gastric juice.
• The most effective chemicals are the monoterpene
secoiridoid glycosides of gentian. Other extracts
that have been used as bitters include quassia,
quinine (Cinchona) and strychnine (Nux vomica).
The ‘hot’ medicines
• The three most commonly used ‘hot’
medicines include black pepper (Piper
nigrum), cayenne pepper (Capsicum) and
ginger (Zingiber).
• They are used as metabolic stimulants,
more specifically as a ‘facilitating agent’ to
accompany other herbs whose stimulatory
activity may be augmented.
Resins
• The term ‘resin’ is applied to the sticky waterinsoluble substance of complex chemical
nature often exuded by the plant, soon
hardening to protect an injury. Resins are
usually produced by the plant in ducts or
cavities, but may also be found in special
cells elsewhere, e.g. in elements of the
heartwood of guaiacum and the internal cells
of the male fern.
Resins
• The term may also be applied to that part of
a plant that is soluble in ether or alcohol (e.g.
guaiacum resin and kava resin). Resins are
used as astringents and antiseptics of the
mouth and throat and have also been applied
to inflammatory conditions of the upper
digestive tract.
Resins
• Propolis, a product collected by bees from
resinous plants, is used in herbal medicine,
although it is not strictly herbal in nature. The
product is also used in homeopathy.
• A ‘balsam’ (e.g. balsam of Peru and balsam
of Tolu) is an oleoresin containing a high
proportion of aromatic balsamic acid.
Saponins
• Saponins are glycosides that produce frothy
aqueous solutions. Plants containing these
compounds (e.g. Quillaia saponaria) have been
used for centuries as gentle detergents.
• Decoctions of soapwort (Saponaria) have been
used to wash and restore ancient fabrics. They
also have haemolytic properties and when
injected into the bloodstream are highly toxic.
When taken by mouth saponins appear to be
comparatively harmless.
• Sarsaparilla is rich in saponins but is widely
used in the preparation of non-alcoholic drinks.
Saponins
• Two distinct types of saponins may be
recognised.
• The steroidal saponins are of great
pharmaceutical importance because of
their relationship to compounds such as
the sex hormones, cortisone and the
cardiac glycosides.
• Some species of the yam (Dioscorea spp.)
and potato (Solanum spp.) contain
steroidal saponins.
Saponins
• The second group of saponins is known as
the pentacyclic triterpenoid saponins. This
includes quillaia bark and liquorice root
(Glycyrrhiza). The former is used as an
emulsifying agent, the latter as a
flavouring agent, demulcent and mild
expectorant.
Tannins
• This is not a specific phytochemical group
but a name for a group of chemicals that
have a particular characteristic.
• The term ‘tannin’ was first applied by
Seguin in 1796 to denote substances
present in plant extracts that were able to
combine with animal proteins in the hides,
preventing putrefaction and converting
them to leather. Most tannins have
molecular masses (Mr) of about 1000–
5000 and many are glycosides.
Tannins
• Tannin-producing drugs will precipitate
protein and have been used traditionally
externally as styptics, and for burns and
weeping eczema, and internally for the
protection of inflamed surfaces of the
mouth and throat.
• They are also claimed to be
antioxidants.Witch-hazel (Hamamelis
virginiana) is a tannin-containing drug
used principally for its astringent
properties.
Volatile oils
• Volatile oils are volatile in steam. They differ
widely in both chemical and physical properties
from fixed oils.
• They are secreted in oil cells, in secretion ducts
or cavities, or in glandular hairs, and are
frequently associated with gums and resins.
With the exception of oils derived from
glycosides (e.g. bitter almonds and mustard oil),
volatile oils are generally mixtures of
hydrocarbons and oxygenated derivatives
mainly responsible for odour and taste.
Volatile oils
• In some oils (e.g. oil of turpentine) the hydrocarbon
portion dominates whereas in others (e.g. oil of
cloves) the opposite is true. Volatile oils are used in
perfumery and cosmetics (e.g. oil of rose, oil of
bergamot), in food flavourings (e.g. oil of lemon) as
well as in medicine.
• Many oils with a high phenolic content (e.g. clove
and thyme) have antiseptic properties, whereas
others are used as carminatives.
• Oils showing antispasmodic activity include
peppermint (Mentha piperita) and camomile
(Matricaria chamomilla).
Phytochemical groups of
constituents
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Alkaloids
Coumarins
Flavonoids
Glycosides
Polysaccharides
Phytochemical groups of
constituents
• Alkaloids Typical alkaloids are basic, contain
one or more nitrogen atoms, and have a marked
physiological action on humans and animals.
• Coumarins Coumarins are benzo-a-pyrones
generally with a hydroxyl or methoxy group in
position 7.
• Flavonoids Flavonoids consist of a single
benzene ring joined to a benzo-c-pyrone
structure.
Phytochemical groups of
constituents
• Glycosides Glycoside is a term that covers
many different combinations comprising a
monosaccharide part (e.g. fructose or glucose)
and a non-sugar part, which may be a simple
phenol, flavonoid, anthraquinone, triterpenoid or
other structure, known as ‘aglycone’.
• Polysaccharides Polysaccharides are polymers
based on sugars and uronic acid.
The preparation and
presentation of herbal medicines
• The medicines are made according to
standards quoted in the appropriate
pharmacopoeias, e.g. British Herbal
Pharmacopoeia.
The preparation and
presentation of herbal medicines
• Herbal medicines may be administered as
crude drugs or extracts.
• The latter include infusions, decoctions and
cold aqueous macerates that can be freshly
prepared by the consumer.
• There are also liquid extracts, tinctures and
solid and dry extracts that are industrially
produced.
• Solid dose forms and topical preparations in
which herbal ingredients have been
incorporated are also available.
Crude drugs
• Crude drugs are extracted by the
consumer as an infusion if the herbs are of
a light fleshy nature or as a decoction if
fibrous and woody (roots and barks). The
advantages are that the extraction is
freshly prepared and is particularly
appropriate for herbs with active
constituents that need to be given hot.
Infusions
• This is the preferred method of extracting
fresh active ingredients from light leafy
herbs.
• The drug may be extracted alone or in the
form of a herbal tea, of which there are
simple (e.g. camomile, peppermint) and
more complex varieties with more than one
active principle and a number of excipients.
• They are convenient when the active
constituents are water soluble.
The herbal tea
• Commercially available medicinal teas are
ready formulated for the consumer and are
usually prepared freshly as an infusion
before taking.
• They contain the following constituents:
- The remedium cardinale
- The adjuvans
- The constituens, corrigens and colorants
The herbal tea
• The remedium cardinale: one or more basic
medicinal agents, e.g. a laxative tea may contain
senna leaves and frangula bark.
• The adjuvans: one or more auxiliary medicines
that enhance the action of the basic medicine or
reduce undesirable side effects. Thus, drugs
with carminative (anise, caraway or fennel)
and/or spasmolytic properties (camomile
flowers, silverweed) may reduce unwanted side
effects of senna.
The herbal tea
• The constituens, corrigens and colorants: fillers
and aesthetic agents to improve aroma,
appearance, colour or texture. Up to 20% of the
tea may be a filler (e.g. raspberry leaves) which
prevents it from separating into its components.
To ensure concordance, herbal teas must be
reasonably palatable; this is especially important
for children. Widely used excipients include bitter
orange peel, orange blossom, hibiscus flowers
and peppermint leaves. Colorants such as
cornflower, mallow and marigold are also used.
Decoctions
• Roots and barks may be extracted using a
decoction method.
Liquid extracts
• Liquid preparations weaker than 1:2 are
usually called ‘tinctures’, whereas 1:1 and
1:2 preparations are called ‘extracts’.
• Tinctures are usually made by maceration
and extracts by percolation.
Applications of herbalism
• Generalised conditions
- Autoimmune conditions
- Acute inflammation of muscles, joints and
connective tissues
- Psoriasis and other skin conditions
Applications of herbalism
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Debility
Chronic fatigue syndrome
Fatigue and debility after illness
Fatigue linked to depression
Support during terminal illness
Fevers
Fevers resulting from infectious causes
Febrile symptoms of non-infectious origin
Applications of herbalism
• Infectious disease
- Acute gastrointestinal, respiratory, and urinary
infections
- Topical bacterial infections
- Minor-to-moderate febrile infections
- Minor-to-moderate chronic bacterial, fungal and
viral infections
• Malignant diseases
- Cancers of varying types
- Symptoms resulting from cancer
- Problems with body systems
Applications of herbalism
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Cardiovascular system
Hypertension
Angina
Ongoing symptoms of cardiac disease
Patients with heart disease are
reported to benefit from treatment with
herbal medicine with fewer side effects
Applications of herbalism
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Gastrointestinal (GI) system
Dyspepsia
GI reflux
Food intolerance and allergies
Constipation and diarrhoea
Genitourinary system
Urinary tract infections
Benign prostate hypertrophy Impaired
lactation
Applications of herbalism
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Menopausal problems
Premenopausal syndrome (PMS)
Nervous system
Anxiety states
Insomnia
Nervous exhaustion
Pain control
Stress symptoms
Applications of herbalism
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Respiratory system
Upper respiratory tract infections
Allergic rhinitis
Bronchitis
Asthma
Skin diseases
Acne
Allergic reactions
Eczema.
Integrating of orthodox and herbal
pharmacy
When to consider
herbalism?
When to consider herbalism
• 1. Where a well-established herbal compound
is being used for a short, self-limiting condition
such as a cold or the flu; when other OTC
medicines would normally be appropriate, the
course of treatment is no more than a couple of
weeks, and no serious adverse effects have
been reported in the scientific literature.
An example of this would be the use of
Echinacea to ward off or reduce the effects of a
cold or ginger to prevent motion sickness.
When to consider herbalism
• 2. In the case of a more serious or ongoing illness,
where no effective orthodox treatment exists and
where there is some evidence from the scientific
literature that a particular herbal compound may help.
In this kind of situation, it is extremely important that
the person be under the close supervision of a
physician well versed in the disease in question and
who has reviewed the available studies on the herb to
be used.
An example of this latter situation would be the use
of milk thistle extract in the treatment of cirrhosis of the
liver.
Applications for topical
formulations
• Burns
• Infestations
• Minor wounds and skin
abrasions
• Oral inflammatory
conditions
• Rheumatic conditions
• Skin eruptions
• Soft tissue injuries –
muscular sprains and
strains.
Examples of the therapeutic
classes of topical medicines
• Demulcents:These are herbs with a
soothing effect to the skin (Aloe vera,
marshmallow (Althaea) and slippery elm
bark (Ulmus fulva).
• Anti-inflammatories: Marigold (Calendula
officinalis) and camomile (Matricaria
chamomilla)
Examples of the therapeutic
classes of topical medicines
• Antiseptics and disinfectants: (Bilberry
(Vaccinium myrtilus), Blackcurrant (Ribes
nigrum), Burnet saxifirage (Pimpinelia
saxifraga), Tea tree oil (Melaleuca alternifolia),
Thyme, garden (Thymus vulgaris)
• Astringents: Decoctions of high tannincontaining drugs suspended in gum tragacanth
are used to treat wounds. Examples are witchhazel (Hamamelis) and tormentil root
(Potentilla).
Examples of the therapeutic
classes of topical medicines
• Other formulations: These include bath
additives, inhalations (e.g. Chamomilla),
mucilages (e.g. slippery elm), plasters
(e.g. belladonna and cayenne), poultices
(e.g. comfrey and marshmallow) and
suppositories. Mullein oil (Verbascum) is
used as eardrops for deafness associated
with earwax, and eyebright (Euphrasia) for
the eyes.
Counselling patients
• Try to choose a medicine that is specific
for the condition being treated; if in doubt
seek advice from the pharmacist or health
shop assistant.
• If you are taking orthodox medicines seek
advice from the pharmacist as to the
likelihood of interactions.
Counselling patients
• Do not take several medicines
concurrently unless specifically directed to
do so by a qualified medical herbalist.
• Use the lowest dose appropriate for the
symptoms being treated; if a little works a
lot more will not necessarily work better
and may be dangerous.
Counselling patients
• Make sure that you understand the
dosage instructions.
• If symptoms do not improve significantly
within 7 days seek advice from your family
doctor.
• Do not self-treat for lengthy periods
without seeking professional help to
ensure that appropriate medication is
being used.
Reasons for negative
outcomes
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Reasons for negative outcomes
• They may be using old herbs (herbs lose
potency with age and the herbs on some
health food store shelves are literally
‘years’ old).
Reasons for negative outcomes
• They may be using powdered herbs in capsules
when really an extract is the only way to get a
concentrated enough dose for physiological
effect (gingko biloba is an example of an herb
best used in concentrate form).
• Even using fresh herbs, many people do not
brew medicinal teas correctly.
• Such a tea should be ‘quite’ concentrated and
the technique for making it is more elaborate
than just dumping a tea bag in water and letting
it sit for a couple of minutes.
Reasons for negative outcomes
• The person may also not be using the herb in
a manner that delivers the active agent.
In many herbs (e.g. valerian), the active
ingredient is an oil and so is not soluble in
water. Hence, steeping it in water and
brewing a tea is not going to get you very
much of the compound. In these cases,
extracts in oil or glycerine (or sometimes in
alcohol) or directly consuming the powdered
herb are the best way to deliver the agent.
Examples of adverse drug reactions
caused by certain herbal ingradients
An abbreviated repertory of
common conditions
An abbreviated repertory of
common conditions
• Anxiety, depression
- Anxiety: Asian ginseng (Panax ginseng)
- Depression: ginkgo (Ginkgo biloba), St John’s
wort (Hypericum perforatum)
• Sedatives: lemon balm (Melissa officinalis),
valerian (Valeriana officinalis), skullcap
(Scutellaria lateriflora)
• Stress: kava (Piper methysticum)
• Benign prostatic hyperplasia: Saw palmetto
(Serenoa serrulata), nettle (Urtica dioica),
African prune tree (Pygeum africanum)
An abbreviated repertory of
common conditions
• Coughs: Coltsfoot, ephedra (Ephedra
spp.), horehound (Marrubium vulgare),
liquorice, mullein (Verbascum thapsus),
thyme (Thymus vulgaris), wild cherry bark
(Prunus serotina)
• Ear and eye
- Ear infections: echinacea (E. purpurea)
- Ear wax: mullein (Verbascum thapsus)
- Eye: eyebright (Euphrasia officinalis)
An abbreviated repertory of
common conditions
• Gastrointestinal:
- Colic: camomile (Matricaria chamomilla)
- Constipation: aloe (A. barbadensis), senna
(Cassia senna), rhubarb (Rheum
palmatum), cascara (C. sagrada)
Dandelion (Taraxacum officinalis)
- Diarrhoea: barberry (Berberis vulgaris),
bilberry (Vaccinium myrtillus)
An abbreviated repertory of
common conditions
• Flatulence and dyspepsia: angelica (Angelica
archangelica), aniseed (Pimpinella anisum),
clove (Syzygium aromaticum), ginger (Zingiber
officinalis), lemon balm (Melissa officinalis),
parsley (Petroselenium crispum), rosemary
(Rosinarinus officinalis), sage (Salvia officinalis),
thyme (Thymus vulgaris)
• Haemorrhoids: horse chestnut (Aesculus
hippocastanumn)
• Motion sickness: ginger (Zingiber officinalis)
An abbreviated repertory of
common conditions
• Nausea and vomiting: ginger (Zingiber
officinalis)
• Heartburn and indigestion: devil’s claw
(Harpagophytum procumbens), gentian
(Gentiana lutea), liquorice (Glycyrrhiza spp.),
peppermint (Mentha piperita) Garlic (Allium
sativum), globe artichoke (Cymara scolymus)
Ispaghula (Plantago ovata)
An abbreviated repertory of
common conditions
• Influenza and colds, sore throat: Echinacea (E.
angustifolia, E. pallida, E. purpurea), elder
(Sambucus nigra), ephedra (Ephedra sinica and
other species), garlic (Allium sativum), golden
seal (Hydrastis), nettle (Urtica dioica), usnea
(Usnea barbata)
• Insomnia: Valerian (Valeriana officinalis), hops
(Humulus lupulus), passionflower (Passiflora
incarnata), lemon balm (Melissa officinalis),
lavender (Lavandula angustifolia)
• Rheumatics: Devil’s claw (Harpagophytum
procumbens), turmeric (Curcuma longa), yucca
(Yucca spp.)
An abbreviated repertory of
common conditions
• Athlete’s foot: myrrh (Commiphora molmol), tea
tree (Melaleuca alternifolia)
• Abrasions, superficial: marigold (Calendula
officinalis)
• Acne: burdock (Arctium lappa), tea tree
(Melaleuca alternifolia)
• Eczema: borage (Borago officinalis), sarsaparilla
(Smilax spp.)
• Psoriasis: cayenne (Capsicum spp.)
• Wound healing: comfrey (Symphytum)
An abbreviated repertory of
common conditions
• Urinary tract infection: cranberrry (Vaccinium
macrocarpen), uva ursi (Arctostaphylos uva-ursi)
• Morning sickness: ginger (Zingiber officinalis),
horehound (Marrubium vulgare)
An abbreviated repertory of
common conditions
• Menopause: alfalfa (Medicago sativa), black
cohosh (Cimicifuga racemosa), sage (Salvia
officinalis)
• Painful menstruation: black cohosh (Cimicifuga
racemosa), blue cohosh (Caulophyllum
thalictroides), cramp bark (Viburnum opulus)
• PMS: agnus castus (Vitex agnus castus), St
John’s wort (Hypericum perforatum)
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