Treatment of Coughs With Herbal Remedies
Francis Brinker N.D.




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Coughing is a common symptom and one of the main signs of respiratory tract
diseases. Roughly half of people who seek medical care during the winter
suffer from inflammatory conditions of the respiratory tract. Acute
respiratory disease accounts for about half of short-term absences from
work. There are many types and causes of coughing which call for a variety
of remedies. The treatment of coughs is one area where the use of certain
herbal remedies remains common today. A number of medical texts from early
in this century help shed light on the specific uses of other herbs which
have been largely forgotten over time.

The Cough Reflex
Coughing is a complex protective reflex which is the normal means of
cleansing the bronchi, the airway tubes to the lungs, of excessive fluids or
unwanted matter. It is associated with other protective processes such as
mucus secretion and narrowing of these tubes. Coughs are usually initiated
by a irritation in the bronchi. However, coughs can also result from
irritation in the ear canal or to the pleural membrane around the lungs.
Causes of coughing include inhaled irritants, inflammation, infections,
fibrosis, blood clots, tumors, or lung congestion from heart insufficiency.
Infections are by far the most common cause of acute coughs.

In the absence of a coughing, material is normally expelled from the
respiratory tract by the action of small hairs on the inner surface of the
respiratory tubes which continually move the coating of mucus at rates of up
to one centimeter per minute. This mucus coating is an important defense
mechanism, since it collects and moves waste matter and inhaled particles
away from the lungs. Respiratory fluids are normally produced by small
glands and goblet cells in the bronchi. These fluids prevent irritation of
the cells lining the respiratory airways.

A number of factors can interfere with the function of the airway lining and
produce the need for coughing. Inflammation from irritants or infection can
increase respiratory fluid production and the number of immune defense
cells, and leading to excessive sputum production. The number of goblet
cells in the bronchial membrane increases in chronic bronchitis or after
chronic exposure to mild irritants. In people exposed to tobacco smoke or
other inhaled irritants the movement of the small hairs is reduced, mucus
production increases, lung cleansing is diminished, and the airways narrow.
Viral infections can interfere with the motion of the small hairs and make
the respiratory fluid thicker.

Reducing exposure to irritants, especially by stopping smoking, is an
important means to avoid arousing the cough reflex. Adequate hydration is
essential to avoid drying of the membranes. Simple steam inhalation can be
adequate for reducing coughs due to irritation of the respiratory airway
below the throat. For infections a number of different types of remedies can
be of benefit.

Dry and Productive Coughs
Most acute infections of the respiratory tract are viral and recovery can be
rapid and spontaneous. The coughs of viral infections are at first dry and
spasmodic, but small amounts of white, thick sputum are usually produced as
they progress. This type of cough can either be relieved with cough
suppressants or made productive by using expectorants. Acute dry coughs may
also be due to inhaled irritants or from a blood clot passing into the
lungs. Chronic dry coughs are noninfective, usually due to either fibrosis
or congestive heart failure which needs to be specifically treated.

As the sputum from respiratory infections becomes thick and more abundant,
the cough becomes productive. Productive coughs usually occur after several
days with a bacterial infection of the bronchi and last about a week. These
coughs become persistent and reoccur periodically in cases of chronic
bronchitis (inflammation of the airway tubes in the lungs). Chronic coughs
with clear or dirty sputum are most likely due to a long-standing irritation
such as from smoking. Sputum colored with pus is indicative of a secondary
bacterial infection, although a yellowish sputum may be caused by an
allergic response. Bacterial respiratory infections should be treated with
antiseptic compounds or, in the case of pneumonia, antibiotics.

Cough Suppressants
Since productive coughs are a necessary means of removing the infectious and
obstructive material, cough suppressants called antitussives should only be
used for dry coughs. The exception would be when the cough is completely
exhausting the patient or preventing sleep. Codeine is the most popular and
frequently prescribed cough suppressant. Since it also dries the respiratory
mucosa, narrows the respiratory tubes, and is a mild respiratory depressant,
it can also aggravate some respiratory conditions. It may also cause nausea,
vomiting, and constipation as well as produce sedation, physical dependance,
or tolerance. The effective suppression of coughs by codeine should not
prevent a more specific treatment of the cause which will give permanent
results instead of only temporary relief.

Coughs originating above the voice box can be appropriately treated with
soothing demulcents. Licorice (Glycyrrhiza) extract is usually thought of as
simply a demulcent with a pleasant flavor, but its derivatives have been
shown to have a central antitussive effect similar to codeine. Licorice is
also considered to be a sedative expectorant. In addition its constituents
have shown antiviral and immune-stimulating effects. About 30 drops of the
fluidextract is used per dose. (Every 15 drops of any fluid extract is
equivalent to 1 gram of the powdered herbal remedy.) However, long-term use
of large amounts of licorice is hazardous since this can lead to potassium
loss and high blood pressure.

An antitussive that works by reducing irritation of the respiratory membrane
at or below the voice box is wild cherry bark (Prunus). Wild cherry bark is
effective for nervous coughs and is often used in short-term infectious
cases or when convalescing. The compound prunasin in wild cherry bark can be
toxic in large amounts but in smaller quantities relieves the irritation of
the mucosa and thereby alleviates coughing. From 20-40 drops of the
fluidextract is normally taken. About 1 1/3 ounce of good quality bark must
be used and extracted by 1 quart of room temperature water (not by boiling)
to make the tea which is taken in 2 ounce doses. A wild cherry bark syrup
preparation is used in 1-2 teaspoon doses but must be carefully preserved to
be of maximum value.
Demulcents and Expectorants

Demulcents contain mucilaginous components that are used for their soothing
effect on irritations of the membrane lining the throat. For this purpose
cough syrups are commonly employed, in addition to acting as a vehicle for
other antitussives or expectorants. Besides sugar in syrups and lozenges,
other commonly used demulcents are honey, glycerin, licorice, and gum arabic
(Acacia), since they also sweeten medicinal preparations. Coughs due to
acute inflammation or from phases of increased irritability in chronic
bronchitis can be treated with mucilaginous herbs in the dose necessary to
gain relief. The soothing effects of these herbs are only present when
prepared as extracts by soaking in water at room temperature. Coltsfoot leaf
(Tussilago) is effective in these cases. Its low content of toxic alkaloids
is safe when taken for short-term use. Marshmallow root (Althea) and
slippery elm bark (Ulmus) are other sources of mucilage for allaying
inflammation and alleviating coughs. Water extracts of mullein flowers
(Verbascum), besides providing demulcent and expectorant effects, inhibit
influenza viruses. Mullein leaf extract is also used for its demulcent
mucilage in irritation from persistent coughs, whether dry or productive.
The juice of plantain (Plantago) has a demulcent mucilage as well as
antibacterial components. Another of its components enhances resistance to
infection.
Expectorants, cough remedies that increase the amount of respiratory fluid
secretions, can be used for both dry and productive coughs. Those known as
sedative expectorants are used for dry coughs to increase respiratory fluid
which produces a demulcent effect on the respiratory membranes. Stimulant
expectorants help decrease the thickness of the secretions in productive
coughs, thus aiding their expulsion, and inhibit bacterial growth by their
antiseptic effects. Some sedative expectorants can also be use for
productive coughs, but stimulant expectorants are considered too irritant
for most dry coughs. Expectorants provide no direct benefit for coughs
arising from irritation in the throat or to the pleural membrane outside of
the lungs.
Sedative Expectorants
Sedative expectorants are used when the membrane is dry, sensitive,
reddened, and swollen or when there is thick, scanty, adherent mucus in the
airway tubes. These remedies have an antitussive action by increasing the
amount of respiratory fluid, thereby producing a soothing effect on the
bronchial membranes, and by decreasing the thickness of membrane secretions,
thus facilitating their removal. The term sedative applies to their effect
on the bronchial membrane irritation which causes coughing, not to their
effect on the body or the mind. Some are called nauseant or irritant
expectorants since they produce vomiting in large doses and they work by a
reflex action due to irritation of the stomach lining. This gastric
irritation causes an increase in membrane secretions in the bronchi. The
nauseant expectorants ipecac (Cephalis), bloodroot (Sanguinaria), and
lobelia (Lobelia) contain active alkaloids that can be toxic in large doses.

Ipecac is used both to liquify thick, tenacious mucus from the airways and
to relieve spasms of the respiratory tubes, particularly spasms from croup.
It reduces bronchial swelling and distress, and the coughing becomes easier.
The main application for ipecac is in bronchial congestion with a dry,
irritable cough. Ipecac is especially indicated when there is irritation
with a continued effort to clear the larynx. It may be the best expectorant
for acute conditions when taken in small, frequent doses insufficient to
cause nausea. An appropriate dose for the syrup of ipecac used as an
expectorant would be 4-8 drops given every two hours. This is much less than
the single 1-2 tablespoon dose taken as an emetic.

Bloodroot is used for harsh, dry coughs with constriction or constant
irritation or tickling in the throat. Its alkaloids produce a direct
antitussive effect on the CNS cough center. Bloodroot is stimulant to the
bronchial membranes, overcoming congestion and increasing membrane
secretions. Considered too harsh a remedy for young children, it is used for
acute or chronic bronchitis or laryngitis (inflammation of the voice box)
when membranes are atonic after active inflammation has subsided. In these
cases bloodroot is used even when there is abundant secretions. The
expectorant dose of the tincture is 5-30 drops, while 1-3 teaspoons will
cause vomiting. Bloodroot and lobelia have both been found useful for the
persistent, harassing cough following influenza.

Lobelia is used in cases of respiratory spasm such as croup, as well as
coughs due to irritation. It is specific for bronchial asthma. It promotes
expectoration and improves respiration in acute bronchitis with coughing,
especially where there is thick mucus with tightness and difficulty
breathing. The potent antispasmodic action of lobelia helps avoid trapping
of the sputum and assists in its expulsion. The expectorant dose of the
tincture is from 5-20 drops, whereas the dose causing vomiting is from 1/2-2
teaspoons. Lobelia is often combined with cayenne when used as an
antispasmodic.

Cayenne (Capsicum) acts as a gastric irritant because of its local action
and stimulates contractions and secretions in the respiratory tract as well.
The initial narrowing of the airways produced by its short-term use requires
that it be used together with an antispasmodic. It inhibits the cough reflex
and has been used internally as an antitussive. Small doses (5 drops of the
tincture) are combined with other remedies and diluted with water.

Bronchial Relaxants
Respiratory tract irritation that causes coughing also causes the bronchi to
narrow. Some sedative expectorants used for dry, spasmodic coughs help
reduce the tightness while not producing gastric irritation. Pleurisy root
(Asclepias) is used for acute bronchitis or influenza with a tight, painful
cough and difficult respiration. When there is a general reduction in
respiratory secretions and the chest is sore from coughing, it is most
beneficial, especially in children. Taken hot, it acts as a diaphoretic to
help control fevers where there is hot, dry skin. One ounce of the powdered
root is extracted with one quart of hot water and a teacupful is taken every
2-3 hours. In pleurisy the cough is short, due to the pain, and hacking.
This type of cough provides no benefit and should be ameliorated with an
appropriate combination containing pleurisy root.

Sundew (Drosera) is called for in similar acute or chronic cases where the
cough is dry, irritable, and persistent, particularly if it is hoarse,
resonant, or explosive. Nervous coughs or spasmodic coughs such as during
measles or after whooping cough are treated with small doses to advantage.
The dose of the fluidextract is from 5-20 drops. Sundew and pleurisy root
are also useful for the persistent cough following influenza.

Lungwort (Sticta) is used in dry, persistent, irritative coughs with rasping
and wheezing. Where there is asthmatic tightness or spasms such as in croup,
it is useful. The exhaustive cough of acute bronchitis or laryngitis with
short, sharp hacking and darting pains or muscular soreness in the chest
indicates its usefulness. Pain in the back of the neck and shoulders or
shoulder blades from coughing is another indication for lungwort. Red clover
flowers (Trifolium) are used for dry, irritable coughs due to irritation of
the larynx or bronchi and for spasmodic coughs such as occur with measles.

Where coughing is associated with asthma or emphysema, more potent remedies
for opening the air tubes in the lungs should be used along with
expectorants to provide relief for either dry or productive coughs. Ephedra
(Ephedra) is a potent antispasmodic like lobelia which, unlike lobelia, is
not an expectorant. However, ephedra is useful for coughs associated with
airway spasms. In these cases it is always combined with other remedies.
Unfortunately, ephedra is likely to cause rapid heart rate and raise the
blood pressure.

Treating Productive Coughs
In cases of bacterial pneumonia the appropriate antibiotic is indicated by
culturing the sputum. Antibiotics are not necessary for acute bacterial
bronchitis unless there are large quantities of pus in the mucus, persistent
high fever, asthma or emphysema, or underlying systemic conditions
compromising immunity. In all types of pneumonia, whether viral or
bacterial, herbs that enhance immunity are useful to stimulate the body's
response to overcome the infection. Such herbs should also be taken for
viral colds, influenza, and all forms of bronchitis. The most important of
these herbs are the echinacea species (Echinacea). Echinacea should be used
in combination not only with other remedies that help resolve infections but
also those that relieve conditions which lead to coughing. Coughing should
not be suppressed in cases of pneumonia, but the pulmonary congestion should
be relieved.

In treating productive coughs demulcents and antiseptics should be used to
soothe the irritation in the throat from coughing and reduce sputum
production, respectively. Where there is irritation in the voice box
demulcents such as licorice or syrups can also help ease discomfort, even
though local contact is limited to the throat. Peppermint oil (Mentha) and
its component menthol act as a local anesthetic to relieve irritation and is
therefore useful in throat lozenges, as well as being mildly antiseptic.
Antiseptic gargles can be used if there is a bacterial infection in the
throat associated with the cough. Volatile aromatic antiseptics are also
taken internally as expectorants.

Stimulant Expectorants
Volatile antiseptics taken internally are generally as stimulant
expectorants. They do not act as nervous system stimulants, but rather their
tonic and antiseptic actions help to stimulate repair and diminish fluid
secretions due to inflammation. They are eliminated by the lungs when taken
orally. These volatile increase sputum expulsion by stimulating normal
respiratory fluid secretions through their mild irritant effects directly on
the bronchial glands. Besides peppermint oil, commonly used stimulant
expectorants containing aromatic oils include eucalyptus (Eucalyptus),
garlic (Allium), and thyme (Thymus).

Eucalyptus oil and its component eucalyptol are common antiseptic flavoring
ingredients in throat lozenges for coughs. The expectorant vapors are
thereby inhaled to affect associated bronchitis as well. Taken internally
eucalyptus reduces inflammatory respiratory secretions by its antiseptic
action and facilitates expulsion of the sputum.
Garlic releases aromatics which are among the most potent and broad-range
antibiotics from higher plants. Since these aromatics are readily excreted
by the lungs, the use of garlic in the second stage of bronchitis
concentrates its active aromatics where they can be most effective. For
colds that are frequently repeated or become chronic, garlic is often
useful.

Thyme and its oil are antispasmodic, especially for the small airway tubules
in paroxysmal coughs such as whooping cough. Like garlic, its antiseptic
volatiles are expelled through the lungs when taken internally and produce
expectorant activity. Its active aromatic component thymol is used as an
antiseptic in gargles.

Thymol and eucalyptol are also eliminated in the urine and act as an
antiseptic there, but in too large of dosage can produce congestion in the
kidneys. Thyme and eucalyptus oils should not be taken internally in high
doses (less than 4 drops of thyme oil and less than 10 drops of eucalyptus
oil for adults) and should be administered in a vehicle such as honey.
Volatile irritants like these should never be used in any case of acute
kidney inflammation. Garlic is relatively nontoxic but can cause stomach
irritation.

Oral balsamic stimulant expectorants include storax (Liquidamber), Tolu
balsam (Myroxylon), and benzoin (Styrax). Balsams are resinous mixtures with
large proportions of benzoates and cinnamates. These compounds are
expectorant and bacteriostatic. These stimulant expectorants are used
internally for chronic bronchitis. Tolu balsam in particular is combined as
an antiseptic tonic with other stimulant expectorants in cough syrups and
taken for bronchial irritation in persistent and chronic cases and for
laryngitis and sore throat as well. Tolu balsam is used where mucous
membranes are relaxed and atonic with excessive secretions. The usual dose
is 20-40 drops of the tincture.

Aromatic Relaxants
Several stimulant expectorant herbs contain a combination of volatiles with
resinous components. In addition to having these antiseptic expectorant
components, these herbs are also antispasmodic to the bronchial airways.
Elecampane root (Inula) is used in short-term and persistent coughs where
there is abundant expectoration, for chronic bronchitis, or after protracted
colds or influenza. The dose for fluidextract of elecampane is 10-60 drops.

Gum plant (Grindelia) has mild expectorant activity. Gum plant is used
mostly in persistent and chronic bronchitis with spasmodic coughs at a dose
ranging from 30-60 drops of the fluidextract. It is often combined with
other expectorants for rattling coughs with profuse secretion, especially
with yerba santa (Eriodictyon) because of gum plant's bitter taste. An
extract of yerba santa leaves is a useful flavoring vehicle for bitters as
well as acting as a respiratory sedative for debilitating coughs of chronic
bronchitis when there is excessive catarrhal discharge. The dosage of
fluidextract of yerba santa is about 30 drops.

Inhalation Therapy
In treating bacterial infections below the voice box inhaling volatile
antiseptics in steam is the most common method of using many stimulant
expectorants. To achieve the best mucus-dissolving and antiseptic effects,
volatile compounds should be inhaled and not just taken orally. The steam
also helps liquify the sputum so that it can be more easily expelled.
Volatile antiseptics include both essential oils and balsams. The aromatic
vapors of the major volatile constituents have shown antiseptic activity.
Volatile antiseptic expectorants derived from conifers are often used as
inhalants. These include dwarf pine needle or Scotch pine needle oils
(Pinus) and cedar leaf oil (Thuja).

Put in boiling water or a steam humidifier for inhalation the balsams are
used as antiseptics for short-term and persistent laryngitis. The balsams
are combined together in the frequently used Compound Tincture of Benzoin
include 5 parts benzoin, 4 parts storax, 2 parts Tolu balsam, and 1 part
aloe (Aloe). This combination is more expectorant when taken orally in a
syrup base and more antiseptic when used with steam inhalation.

Besides the Compound Tincture of Benzoin other volatile combinations are
commonly inhaled in steam. Pouring boiling water on chamomile (Matricaria)
alone for its antibacterial, anti-inflammatory, and antispasmodic effects or
together with thyme makes another useful steam inhalant. Eucalyptus or
eucalyptol and peppermint oil or menthol are another effective combination.

Topical Treatments
Applied topically to the chest, neck and upper back and covered with a
flannel binder, the combination of eucalyptol, menthol, thymol, and camphor
act as counterirritants in a dry chest pack to relieve pulmonary congestion.

Black mustard seed (Brassica) powder can also be used topically as a
rubefacient and counterirritant. The counterirritant effect is a reflex
action affecting the circulation. Usually 1 part mustard seed powder to 6
parts flour (or 1 to 12 for children, fair-skinned, or sensitive
individuals) is combined and mixed with tepid water to make a paste. The
paste is spread on muslin which is folded to enclose the moist paste. Olive
oil is rubbed on the skin, then the moist plaster is applied until the skin
reddens (from 5 to 20 minutes maximum).wh It is placed over the chest for
acute bronchitis to help relieve congestion. After removal the skin is
washed and oil is again applied. Blistering can occur if the mustard paste
is too strong or the plaster is left on too long.

A topical remedy that used to be quite popular for acute bronchial
infections and cough was compound powder of lobelia (emetic powder). It
consisted of 6 parts lobelia, 4 parts ipecac, 3 parts bloodroot, 3 parts
skunk cabbage (Dracontium), and 1 part cayenne pepper. Cayenne is an
effective rubefacient that does not cause blistering, while skunk cabbage is
an antispasmodic. This combination was sprinkled on a cloth coated with an
absorbable ointment base and then warmed and applied to the chest. This
plaster was used for short-term bronchitis, pleurisy, and soreness of the
chest walls to relieve the pain and inflammation.
Pharmaceutical Combinations for Coughs

Combination cough remedies are commonly available in pharmacies and
groceries stores and often used. In the United States as many as 600
formulations of cough remedies are on sale, and they rank as the fifth most
prescribed class of drugs. In addition to a central antitussive in a
demulcent syrup they typically contain an expectorant, a decongestant, an
antihistamine, an anesthetic. Sometimes they also include an agent for
relaxing airway tubes, an analgesic, an anti-inflammatory, or a medicine for
fever. These medicines often appear to be put together without any logical
rationale for the combination. They are frequently combined to alleviate the
totality of symptoms associated with an upper respiratory infection. Most of
these ingredients are not necessary if the cough alone is all that requires
treatment. For example, the decongestants act on the nose and sinuses,
analgesics are intended for headaches and muscle aches, and antipyretics
reduce fevers. Some have opposing actions, such as antihistamines which dry
the respiratory mucous membranes and the expectorants which increase
respiratory fluid secretion. It is better to use only those agents that are
necessary to avoid side effects.

Though appropriate in selected cases, cough syrup combinations should not be
used routinely. Different cases, and even the same case at different stages,
requires different treatment. The addition of appropriate remedies to a
standard cough syrup base is an appropriate means of using the syrup as a
vehicle without becoming unduly reliant on a particular preformulated
remedy.

ACTIVITIES OF HERBS USED INTERNALLY TO TREAT DRY COUGHS
Antitussive Demulcent Sedative
Expectorant Antispasmodic Antiseptic Immune Stimulant Potentially
Toxic marshmallow x pleurisy root x x cayenne * x x x ipecac x x x sundew x
x ephedra * x x licorice * x x x x lobelia * x x x plantain x x x wild
cherry * x x bloodroot * x x x x lungwort x x red clover x x coltsfoot x x
slippery elm x mullein * x x * These remedies may also be used for some
productive coughs.

ACTIVITIES OF HERBS USED INTERNALLY TO TREAT PRODUCTIVE COUGHS
Antispasmodic Stimulant
Expectorant Antiseptic Immune
Stimulant Potentially
Toxic garlic x x echinacea * x x yerba santa * x x x eucalyptus x x x gum
plant * x x x elecampane x x x storax x x peppermint x x Tolu balsam x x
benzoin x x thyme x x x x * These remedies may also be used for some dry
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