Treatment of Coughs With Herbal Remedies

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
fluid extract 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 fluid extract 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.

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