Diuretics are agents (both herbs and drugs), that help the body to rid itself of excess fluids
by increasing the rate of urine production by the kidneys. The accumulation of excess fluids in tissues, known as
edema, is symptomatic of a wide range of heart, kidney, liver, and other disorders. Such disorders must be addressed,
but diuretics may be used in conjunction with other herbs. Many diuretics alter the excretion of electrolytes by the
kidneys; these electrolytes, such as sodium and potassium salts, are involved in many body processes including the
regulation of blood pressure, nerve impulse transmission and muscle contraction. An electrolyte is a chemical
that, when dissolved in a suitable solvent, forms a medium that conducts an electric current.
In Herbal Medicine, with its ancient traditions, the term diuretic has come to imply a herb that has some sort of beneficial action on the urinary system. Thus not only are diuretics as such included, but can also urinary demulcents and anti-inflammatory
remedies. This can, regrettably, lead to confusion when selecting remedies for a particular individual. Hopefully what
follows will clarify this situation to some degree.
How do Diuretics Work
If we limit ourselves to the strict
sense of the word, there appear to be two broad groups, those that increase kidney blood flow and those that reduce
the water reabsorption in the nephrons of the kidney.
The first group includes not only diuretics such as Broom
but all the herbs that are cardio-active and circulatory stimulants. These increase the blood flow in the kidney by effects
on the heart or elsewhere in the body. Because there is more blood passing through the kidney, more urine is
produced. Caffeine-containing herbs such as Kola, Guarana, Tea and Coffee also have this effect
* The second group work in a number of different ways, but they cause diuresis be cause some of their constituents are secreted
via the kidney. This may change the osmotic balance causing more water to be lost. This appears to be the case
with Dandelion Leaf, Couch grass and Corn silk. Others work by irritating there absorption mechanism in some way,
either through volatile oils, saponins or alkaloids.
Varieties of "Diuretic"
In addition to the herbs that
have a markedly diuretic impact, there are others called "diuretics" that have other than a primarily diuretic effect
upon the kidneys. The phytotherapist has the option to reduce inflammation through demulcents and
anti-inflammatories. Infection can be treated directly through "diuretics" that are anti-microbial. Similarly, if these
problems are associated with stone formation there are plants known as anti-lithics, discussed in the section on
Anti-inflammatory: Celery Seed, Cleavers, Corn Silk, Couch grass, Gravel Root
Gravel Root, Hydrangea, Stone Root
Anti-microbial: Bearberry, Buchu, Couch grass, Juniper,
Astringent: Agrimony, Bearberry, Broom, Horsetail, Kola, Yarrow
Corn Silk, Couch grass, Stone Root
Diuretics for Different Parts of the Body
The core of the model
used throughout this book is that each herb has a range of actions and that some have specific system and organ
affinities. The fundamental importance of both the urinary system and diuretics, emphasize the possibilities if secondary
actions and system affinity is taken into account. To clarify this consider the following: