Medical Astrology is a branch of Astrology that utilizes the horoscope to identify weak areas of the body that may be predisposed to illness as well as potential treatment options.
A good way to begin understanding medical astrology is to gain an understanding of how the astrological signs of the zodiac relate to the various parts of the body. In medical astrology each sign of the zodiac is associated with an anatomical location in the body. The specific indications of each sign in terms of parts of the body are derived from the sign's position within the wheel of the zodiac.
Health issues are largely governed by the sixth house and its planetary ruler, along with the ascendant and its planetary ruler in a nativity (personal birth chart). The situation of the Sun and Moon are also significant, as are the placement of Saturn (chronic conditions) and Mars (acute conditions). Naturally the nativity must be viewed as a whole and these factors seen in context, especially with regard to the Decumbiture chart, the horary tool for astrological diagnosis.