Pathogenesis of Amavata
By Todd Caldecott
The Madhava Nidanam states that when the digestive fire is weak and ama
is allowed to accumulate, it moves to the different locations of Kapha
in the body (Srikantha Murthy 1995, 95). Kapha is derived from the
Sanskrit root word 'shlesh,' which means 'to embrace.' Thus, Kapha
binds the joints together, nourishing and protecting the articular
surfaces (Srikantha Murthy 1994, 169).
Like ama, Kapha is heavy (guru),
moist (snigdha) and cold (shita) in nature. For this reason, ama
typically associates with Kapha before the other two doshas. According
to the Madhava Nidanam, when ama is allowed to accumulate in the joints
they become congested with a "…hard, waxy material" (i.e. Kapha). Soon
the circulatory channels (dhamanis) that supply these regions become
congested as well. Eventually this blockage affects the heart (hrdaya),
which then becomes the "…seat of the disease" (Srikantha Murthy 1995,
Once Kapha has become vitiated the other doshas eventually become
involved. To restore homeostasis the body will initiate local
inflammatory processes (i.e. Pitta) in the joint in order to 'cook' the
accumulated ama. Despite the inflammatory component of this condition
however, the hallmark of amavata is the progressive pathological
influence of Vata in the synovial joints, and the resultant joint
The pathogenesis of amavata bears some similarity to the recently
described intestinal permeability syndrome (IPS). The impetus for IPS
is a process by which some agent or combination of agents initiates an
inflammatory response in the digestive tract. Persistent
gastrointestinal inflammation eventually disrupts the integrity of the
mucosal lining of the gut, and tiny perforations allow for molecules
larger than usual to pass across this barrier, including molecules from
dietary protein and fats, bacteria, parasites and fungi.
In response to
this infiltration, an immune response is initiated and the body begins
to manufacture specific antibodies to these antigens. Unfortunately,
many tissues have antigenic sites almost identical to those substances
that pass across a permeable intestinal wall. Once activated, these
antibodies then circulate and 'look' for more antigens. When an antigen
is found, such as a tissue that has similar markers to an exogenous
antigen, the antibody initiates an immune response and the tissue
begins to be destroyed (Galland 1993).
The differences between IPS and
amavata are obviously significant, with each using an entirely
different physiological model. Nonetheless if we can translate the
antigens described in IPS into the ama identified in Ayurvedic
medicine, the two models become strikingly congruent (Kumar 1997, 94).
Although amavata is primarily a disease of Vata, it is differentiated
into three basic subtypes, namely, Vata, Pitta, and Kapha. This
differentiation allows the practitioner to identify a greater range of
subtlety within the diagnosis and treatment of amavata.
Where Pitta is
involved the joints appear red and feel hot, and the patient complains
of a burning, searing pain. With Vata the pain is severe, and migrates
from place to place. With Kapha the pain is less, but there is more
stiffness and immobility, often combined with sensations of itching.
There may also be a combination of any two or three of the doshas. If
one dosha is involved the condition is said to be easy to cure. With
two doshas the situation is more difficult, and with all three doshas
in a state of vitiation the condition is said to be incurable.
Similarly, when there is migrating pain and severe inflammation in the
joints of the hands, feet, head, heels, waist, knees and thighs,
amavata is said to be incurable (Srikantha Murthy 1995, 95-96)."
Todd Caldecott is a clinical herbalist, and known for his crisp and informative articles on Ayurveda. You can write to him at email@example.com, and visit him at ToddCaldecott.com.