Medical Astrology - An Introduction

So you're not lost during each astrology season summary...

Table of Contents

What is Medical Astrology?

Medical astrology is a system of association between celestial bodies (astrology) and body systems, disease, and treatment (medicine). In this system, natal birth charts and current astrological transits influence individual and societal health. This system has roots in African, Ancient European, Ayurvedic, Native American, and Traditional Chinese Medicine traditions. Just as the moon’s orbit pushes and pulls on the ocean, so does the movement of celestial bodies push and pull on every aspect of human existence. Medical astrology is one way we understand how the stars influence our physical, mental, and energetic health.

There are many ways to describe these connections between the cosmos and the human body. Here are the modalities I use most in my Astrology Summaries and my understanding of human constitutional types. 

Planetary Rulership and Body System Correspondence

If you’re familiar with Roman or Greek mythology, this section will be easier for you to understand. The planets are named after Greek or Roman Gods and embody their qualities in astrology. Each zodiac sign is ruled by at least one planet and each sign corresponds to a different human organ system based on their rulership.

Classical Planets and Luminaries

These planets and luminaries (the Sun and Moon) can be seen with the naked eye. They have been studied by astrologers since antiquity.

The Sun - Leo - Heart and Spine

The Sun itself was considered a God, called Helios in Greek. It corresponds with Fire, and represents our core identity and the Ego. The sun is associated with the heart and the spine. Sun ailments include heart disease and spinal disorders.

The Moon - Cancer - Body Fluids 

The Moon was also considered a God, personified by the Greek Goddess Selene. It corresponds with Water and represents our hidden emotions, intuition, and memory. It rules over fluid-releasing systems like the uterus, breasts, lymphatic system, and digestive system. Moon ailments include menstrual disorders, edema, and lactation complaints.

Mars - Aries (+ Scorpio in the Classics) - Arteries and Muscles

Mars is named after the Roman God of War. It corresponds with Fire and represents action, willpower, and energy. It rules over the body structures necessary for exertion like the arteries and the muscles. Since Mars is a planet of action, it rules over ailments related to mental or physical over-exertion like headaches, inflammation, and trauma wounds.

Venus - Taurus, Libra - Fluid Regulating Systems

Venus is named after the Roman Goddess of Love and Beauty. It corresponds with Water and represents our value systems, pleasure, romance, and art. It rules over body structures regulating fluids such as the kidneys and parathyroid glands. Ailments associated with Venus include urinary tract disorders.

Mercury - Gemini, Virgo - Nervous System

Mercury is named after the Roman God of Commerce, Communication, and Travel. It corresponds with Air and represents communication and intellect. Language and intelligence are produced by complex brain activity, so Mercury rules over the brain, nerves, and the respiratory system (your voice box is part of your respiratory system). Ailments related to Mercury include nerve disorders, anxiety, and breathing disorders.

Jupiter - Sagittarius ( + Pisces in the Classics) - Generative Systems 

Jupiter is named after the Roman God of the Gods, Sky, and Thunder. It corresponds with Air and Wood, and represents growth, luck, philosophy, and religion. It rules over generative body structures like the liver and the pituitary gland. Ailments related to Jupiter involve rapid or uncontrollable growth, like cancer.

Saturn - Capricorn ( + Aquarius in the Classics) - Skeleton

Saturn is named after the Roman God of Time, Wealth, and Harvest. It corresponds with Earth and represents ethics, structure, responsibility, and karma. While Jupiter encourages expansion, Saturn demands restraint (and often gets an undeserved bad rep for it). Saturn rules over our protective and foundational body structures like bone and skin. Saturn ailments include blockages, age-related decline, and bone disorders.

Modern Planets

These planets were discovered in the 18th century and aren’t included in ancient or medieval texts. Some astrologers only assign rulership to classical planets.

Uranus - Aquarius - Parasympathetic Nervous System

Uranus is named after the Greek God of the Sky and Heavens. It represents individuality, self-determination, invention, and revolution. It is considered the higher octave of Mercury (meaning Uranus expands on the ideals of Mercury). Uranus rules over the parasympathetic nervous system and the endocrine system. Uranus ailments include overexcitable nervous disorders, spasms, and seizures.

Neptune - Pisces - Consciousness

Neptune is named after the Roman God of the Sea. It represents collective consciousness, idealism, dreams, and artistry. It is the higher octave of Venus. Neptune rules over the thalamus and pineal gland. Neptune ailments include hallucinations, addiction, and confusion.

Pluto - Scorpio - Reproductive System

(Yes, Pluto is a planet in astrology no matter what the IAU says. )

Pluto is named after the God of the Underworld and Death. It represents transformation, systems of power, and unearthing forgotten or suppressed truth. It is the higher octave of Mars and rules over transformational bodily structures like the reproductive organs and destructive organs like the pancreas. Pluto ailments include sexual disorders, degenerative diseases, and genetic disorders.

Elements: Water, Fire, Earth, Air 

Elements are the building blocks of all life on Earth. In Hellenistic Astrology, the Four Elements also categorize each zodiac sign. The characteristics of each element are fairly intuitive! I don’t like relying on stereotypes, so I do my best to explain each characteristic in a way that speaks more to the neutral essence of the element and not the ways these elements manifest as behavior, whether that behavior is positive or negative. Basically, I won’t be asserting that all water signs are crybabies or that all fire signs are egotistical.

Water - Emotion and Intuition

Consider the vastness and mystery of the ocean. Water represents the parts of us that aren’t always visible: our inner emotions and our intuition. Water represents a strong connection to intuition and the inner emotional world. In our body, Water relates to our bodily fluids.

Fire - Willpower and Sense of Self

When we speak about our “inner fire,” we are speaking of our motivation and the fuel source of our life. Fire represents a deep connection to willpower and sense of self. In our body, Fire relates to heat generation and enzymatic processes.

Air - Change and Collectivism

When we think of air, we think of weightlessness and omnipresence - it spreads and resists confinement. Air represents movement, change, impermanence, and collectivism. In our body, Air relates to circulation and hollow organs.

Earth - Longevity and Stability 

When we think of Earth we think of soil, which provides us with food. The Earth has been maintaining life for over 3 billion years, so Earth represents longevity, permanence, and dedication. In our body, Earth relates to our body’s framework and solid organs.

In Traditional Chinese Medicine, the 5 Elements are Wood, Fire, Earth, Metal, and Water. In Ayurveda, the Elements are Ether, Air, Fire, Water, and Earth. Ayurveda further categorizes the elements into Doshas (constitutions), which are Pitta, Vata, and Kapha. (I’m very fond of the Ayurvedic system, so that might need to be a separate post.)

Modes: Cardinal, Fixed, Mutable

The modes represent how each zodiac sign reacts to its environment. Each mode encompasses 4 signs and each sign embodies a different element. so while all cardinal signs share some similarities, there is still nuance among them influenced by their element and planetary ruler.

Cardinal - Aries, Cancer, Libra, Capricorn

Cardinal signs start each season (spring, summer, fall, and winter). They tend to initiate and lead in their respective elements. Cardinal Fire values leading with the self, Cardinal Water values leading with intuition, Cardinal Air values initiating new and varied connections, and Cardinal Earth values laying the first stones to a long-lasting foundation. In our bodies, these represents functions that lead, protect, and nourish the organism (adrenal system response, ingestion, and movement).

Fixed - Taurus, Leo, Scorpio, Aquarius

Fixed signs are in the middle of the season. They tend to stabilize and build up the momentum of cardinal energy. Fixed Earth values building and sustaining life. Fixed Fire tends to build the Self and one’s passions. Fixed Water seeks to dive deep into the waters of truth. Fixed Air seeks to widely disseminate their ideals for the collective good. In our bodies, the fixed signs represent our core autonomous functions (circulation and autonomic nervous system processes). These autopilot systems need to function 24/7, because even a small irregularity in heart beat or respiration can have negative impacts.

Mutable - Gemini, Virgo, Sagittarius, Pisces

Mutable signs close out the season. They tend to change, improve, and clear away to make way for new and better things. Mutable Air values the fluidity of ideas and opinion. Mutable Earth seeks to improve through repeated self-editing. Mutable Fire seeks to expand its worldview through varied experiences. Mutable Water values trust and taking a leap of faith into unknown waters. In our bodies, the mutable signs correspond to body functions that assimilate nutrients from the external environment (respiration and digestion/absorption). They are the most sensitive to environmental changes.

Putting it Together

Let’s tie this all together. Each zodiac sign can be categorized by planetary rulership, elemental influence, and temperament. You can start to build an understanding of a sign by breaking it down into planetary ruler, element, and mode. If we look at Aries, we know it is a cardinal fire sign ruled by Mars. Therefore, we can describe Aries as an action-oriented (Mars) sign that finds it easy to initiate (cardinal) projects related to their passions (fire). Relating to the body, the planets indicate whole body systems, while astrological signs are assigned to body regions. Considering the cardinal and Fire energy alongside Mars, Aries embodies mental and physical stimulation. Additionally, Aries is the “head” or beginning of the zodiac, so the body region is the head, face, and eyes. In general, the body region each signs rules over descends as we move from the first sign (Aries) to the last sign (Pisces). It might seem a little confusing at first, but you’ll soon see the patterns with practice!

There are other ways to further categorize the signs, but I mostly stick to these 3 in my Astrology Summaries. And now you’re ready to understand the energetics of any given transit and the monthly Astrology Summaries in the newsletter.


Morrell, Peter. “ MEDICAL ASTROLOGY AND ASTROLOGICAL MEDICINE.” Medical Astrology and Astrological Medicine, 1999,

Phillips, Laura. “Medical Astrology: Science, Art, and Influence in Early-Modern Europe.” Yale University Library, Accessed 18 Mar. 2024.

Reed, Theresa. Astrology for Real Life: A Workbook for Beginners. Weiser Books, an Imprint of Red Wheel/Weiser, LLC, 2019.

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