Musca Domestica: A Homeopathic Proving of the House Fly

Introduction

The New York School of Homeopathy conducted a formal homeopathic proving of Musca domestica (common house fly), directed by NYSH Director Susan Sonz, C.C.H., I.H.C., and Robert Stewart, C.C.H. This represents the first proven homeopathic remedy derived from the house fly itself, though a parasite of the fly (Trombidium) was previously studied.

The researchers note the surprising absence of this common substance from the materia medica despite humanity’s long association with the insect. As one source characterizes insects generally: “Something in the insect seems to be alien to the habits, morals and psychology of this world.”

Natural History

Scientific Classification

Kingdom: Animalia
Class: Insecta
Phylum: Arthropoda
Order: Diptera
Family: Muscidae

Musca domestica belongs to the muscoidea family, sharing the materia medica with other arthropods primarily represented by spiders, and Cantharis from the coleoptera order. The mosquito (Culex) represents another dipteran family member in homeopathic use.

Reproduction

The common fly demonstrates remarkable prolific capacity. Beginning in April, a single fly may produce offspring exceeding the entire human population by a factor of four within one season. Natural predators, particularly spiders, provide population control.

Physical Characteristics

Unlike vertebrates, flies possess an external exoskeleton rather than internal skeleton. Their wings function as vibrating skin extensions from the thorax enabling flight, requiring continuous maintenance for functionality.

The head features two large compound eyes composed of hundreds of hexagonal lenses permitting 360-degree fractured vision, plus three smaller ocelli between them.

Like butterflies and moths, flies undergo complete metamorphosis: egg → maggot → pupa → adult fly. This dramatic transformation distinguishes them from insects that merely increase in size through successive molts.

Feeding Habits

Flies possess unique feeding mechanisms. They taste through their legs while walking across potential food surfaces. Lacking true mouths and chewing apparatus, they cannot digest solid food. Instead, they extend a soft proboscis emitting saliva that dissolves material, then suck the liquefied substance through this straw-like structure.

Preferred food sources include garbage dumps, trash cans, fecal matter, unprotected cooked foods, and spoiled/rancid substances. This indiscriminate feeding makes them vectors for disease transmission.

Note: The proving used a newly-hatched fly before feeding, explaining the absence of expected digestive symptoms.

Behavioral Characteristics

The authors caution against anthropomorphic interpretation in homeopathic assessment. Several fly characteristics were confirmed through proving and limited clinical experience:

Water Connection: Unlike most insects associated with dry warmth, flies connect deeply with moisture and earthiness. They congregate at wound edges and farm animal eyelids, demonstrating insatiable thirst due to their liquid diet. Water themes recurred throughout many provers’ experiences.
Skin Affinity: Enclosed in exoskeletons without true skin, flies show special attraction to wounds and abraded skin. Some species deposit eggs in living animal skin; hatching maggots create ulcerative patches. Numerous skin eruptions appeared in the proving.
Filth Association: Corruption, decay, garbage, and fecal matter constitute primary fly environments. Provers experienced similar themes—garbage obsession, corruption sensation, “perverted” imagery, and disgust with surroundings.
Prolific Nature: Flies’ incredible reproductive capacity correlated with increased libido among provers. Notably, gender preference remained ambiguous; homosexuality and pornography appeared as recurring themes.
Devilish Connection: Historically linked to Beelzebub, sulfur smell and rotting associations appeared among prover delusions and olfactory sensitivity.
Sweet Attraction: Over five provers craved sweets, particularly chocolate.
Cold Sensitivity: Flies slow with temperature drops, dying with first frost. Nearly all provers experienced increased cold sensitivity.

Obtaining the Source

NYSH sought to expand the materia medica from the animal kingdom using a common substance. A fly pupa was sent to Michael Quinn at Hahnemann Pharmacy for proper classification and potentization to 30c in twelve vials. The sex of the specimen could not be determined, and its significance remains unclear.

The proving followed methodology detailed in Jeremy Sherr’s The Dynamics and Methodology of Homoeopathic Provings. Separate instruction pages for provers and supervisors were distributed January 27, 1999. Two weeks of baseline journaling preceded remedy distribution on February 10. Each prover called supervisors after dosing, instructed to avoid second doses if symptoms appeared.

The Proving Process

Initial complications included: one prover took the remedy during severe illness (eliminated); another discovered pregnancy before distribution (allowed only pillow placement under head).

Ten viable provers remained. One master prover feared no symptoms would emerge; the other anticipated overreactions. Results fell between extremes.

Unusual Reactions

Prover #1: Developed severe mumps within days of remedy ingestion. While causation remains unknowable, exposure seems likely (school teacher). Interestingly, Culex mosquito shows “pain as if going to have mumps” in Kent’s repertory. Whether the remedy triggered development or merely accelerated inevitable illness cannot be determined.

Prover #2: Had suffered severe rheumatoid arthritis pain for fifteen years, tested positive for RA, experiencing heaviness, tiredness, and feeling “old.” After first remedy dose, she napped and dreamed of flying room-to-room throughout her house. Upon waking, her pain had vanished. While not a complete cure of her case, this profound relief persisted throughout the proving.

General Reactions

Provers experienced strong irritability affecting even supervisors (some provers became angry with supervisors). After learning the substance was “grotesque,” one prover expressed upset. At the six-week extraction meeting, nearly all provers agreed to participate in future provings.

Both master provers slept with remedy under pillows and experienced strong symptoms. Robert Stewart described “a feeling of being a depressed Nux Vomica.” Irritability affected everyone strongly.

Speculation about the substance was common. Notably, one prover guessed cockroach, another’s wife believed it was a fly.

Extraction Meeting Themes

Discussion centered on putrefaction, rotting garbage, maggots, corruption, excrement, toilets, sewers, tunnels, and dirty water.

Water Dreams: Probably the most common symptom—recurring dreams of lakes, oceans, beaches (often dirty/dreary), Mediterranean scenes, public bathhouses, swimming, floating, and falling into water.

Other Vivid Dreams: Tunnels, underground houses, trapdoors, cellars, tree roots, dead people, fire, houses, flying, lightness, being covered in excrement (consistent with fly reproduction), and baby elephants covered in mud/oil.

Sexual Dreams: Four provers experienced recurring sexual dreams. Three had dreams involving gay men or homosexual issues. One dreamed of rape. One dreamed of committing unlawful acts; another dreamed of being crime victims. Dreams included imprisonment, police, and soldiers.

Mind Symptoms

Confusion: General confusion of mind appeared commonly—possibly from introspection expectations, but notable gender confusion emerged. A young child whose parents both took the remedy called his mother “Daddy” and father “Mommy.” One reliable prover experienced strong lurking homosexuality feelings, believing men were watching, touching, and attracted to him. He acknowledged homophobic reaction as entirely new.

Fastidiousness: Three provers reported compulsive cleaning until everything reached perfect order—definitely new for them.

Isolation: Strong sensation of isolation appeared—one supervisor insisted email-only communication (violating instructions); another stopped all communication, leaving the prover completely isolated. Many expressed “forsaken feeling” and self-pity, though unclear whether these exist independently or feed each other.

Physical Symptoms

Heaviness and Lightness: Most common symptom was limb heaviness; some experienced heaviness alternating with lightness. Seven of ten provers felt one or both sensations. Numbness appeared in extremities, particularly arms.

Skin Eruptions: Every prover with previous herpetic eruptions experienced outbreaks. Notably, these same provers experienced their longest relief periods ever following the proving.

Other Physical Symptoms: Lack of vital heat, chocolate craving, increased cold sensitivity, and constipation without urging appeared frequently.

Symptoms Shared by At Least Four Provers: These appeared unmistakably part of the remedy’s action.

Special Consideration: Prover #5

After deliberation, every symptom from this exceptionally sensitive prover was deemed valid. Jeremy Sherr’s description of his exceptionally sensitive prover during the Eagle proving provided precedent—a person capable of becoming almost unified with the remedy, perceiving it deeply.

Prover #5 demonstrated pre-remedy sensations: he smelled the remedy and detected “quite ripe peaches.” He felt drawn to garbage and brackish subway water, constantly using language like “being surrounded by corruption and decay,” and visualized garbage as “moving.” He believed the remedy concerned garbage and was “degrading and decomposing.”

One week into proving, he opened a random book page describing maggots cleaning pearls—he recognized this as significant. His wife (somewhat fatigued by his symptoms) eventually guessed “sea worm or fly.”

He experienced numerous skin eruptions, though his herpes didn’t recur for another year minimum. His one-year TMJ condition resolved completely.

Prover #5 reported feeling like “an animal with eyes darting about,” experiencing visions of a dead squirrel with beetles and wasps burrowing into collapsed eyes. Numerous haunting images appeared alongside fears and obsessive homosexuality thoughts. Every symptom seemed relevant, and he appeared to enjoy the experience—seemingly feeling temporarily “possessed” on “an interesting trip.”

Symptom Summary by System

Generalities

Food and Drink Desires/Aversions:

Bacon, beer (morning), chocolate (provers 3, 4, 7, 9), coffee, sour foods, cheese (prover 5)
Water aversion (prover 5)
Cheese aggravation (prover 5)
Vinegar desire

Physical States:

Heaviness externally (provers 1, 2, 4, 5, 6)
Heaviness internally (provers 2, 3, 5, 6, 7, 8, 9)
Alternating heaviness/lightness (provers 2, 3)
Lack of vital heat (provers 5, 6, 7, 8, 9)
Heat alternating with chill (prover 5)
Lassitude (provers 2, 6, 9)
Paralysis sensation (prover 2)
General weakness (nearly all)
Weakness with restlessness
Storm weather aggravation (prover 5)

Mind Symptoms (Extensive)

Activity and Anger:

Desire for physical exercise
Easy anger (provers 2, 3)

Anxiety:

General anxiety (provers 5, 6, 8)
Anxiety with time fixation (prover 4)
Anxiety when alone
Anxiety with congestion
Anxiety driving from place to place
Health anxiety (provers 1, 2, 4)

Aversions and Behaviors:

Aversion to certain people, especially old women (prover 5)
Aversion to company (prover 5)
Awkwardness (provers 2, 5, 7)
Confusion of mind (provers 1, 4, 7, 8, 9)
Sexual identity confusion (provers 3, 5, 6, 8, 10)
Conscientiousness about trifles (prover 6)
Cursing (provers 1, 2, 3, 5)—frequent use of “shit” even during extraction

Delusions (extensive list):

Being watched (prover 5)
Dead and alive again (prover 1)
1000 fingers scratching body
Everything dirty/foul
Floating on man’s back (prover 2)
Followed by men
Followed by garbage
Hearing retching (prover 5)
Garbage is beautiful (prover 5)
Garbage is moving (prover 5)
Beautiful things everywhere (prover 9)
Frenzy of hands while washing face (prover 5)
Being an animal (prover 5)
Animal eyes darting (prover 5)
Visions of dead animals with insects eating eyes
Body and mind separation (prover 5)
Feeling inferior and superior simultaneously (prover 2)
Feeling lighter (provers 2, 3)
Metamorphosis (prover 1)
Kaleidoscopic vision (prover 1)
Seeing 100 eyes (prover 5)
Seeing insect eggs and fish eggs (prover 5)
Maggots, vermin, insects imagery
Feeling more masculine (prover 3)
Separated from group (prover 9)
Surrounded by corruption/decay (prover 5)
Smell delusions
Talking as if asleep (prover 1)
Feeling unappreciated (provers 1, 2, 3, 9)
Foul water visions
Feeling younger (prover 2)

Emotional States:

Despair
Romantic love desires (prover 9)
Vacation/holiday desires (prover 5)

Dreams (Extensive)

Major dream themes included:

Abortion, sick babies, beaches, betrayal
Black oily globs, blood, boats, bombs
Cats, criminals, crypts, corruption, decomposition
Dead friends/relatives, disgusting images (provers 5, 9)
Dirt (prover 5), black dogs, drowning
Dying of cholera (prover 5)
Elevators, excrement (prover 5)
Factories, falling (prover 8), fire (provers 6, 8, 9)
Floods, flying (prover 2), flying room-to-room
Fish, floating (prover 2), ghosts
Glass buildings, grass, games
Red hair, horses, homosexuals
Houses (provers 2, 5, 7, 8), islands
Italy/Mediterranean images (provers 2 and others)
Landlords, lewd/lascivious dreams with orgasm
Looking down from above, marriage/weddings
Money, monsters, murder, nuns
Pedophilia, picking sores until bleeding (prover 5)
Police (provers 5, 6), pregnant, pursued
Prostitutes, rape, soldiers (provers 5, 7)
Red dress, Russian soldier/Grand Army (prover 5)
Sewers, sexual dreams, sexual violence
Sharks, skating, surgery, swimming
Threatening (provers 3, 6, 8, 9), toilets
Trolls/crones, tumors, tunnels
Violence, war, water (provers 5, 6, 8, 9—recurring)
Dirty water (prover 5), swimming in water
Falling into water (prover 9), worms
Vivid dreams generally

Other Mind Symptoms:

Dwelling on past disagreements (provers 2, 3)
Elation (provers 2, 4, 5)
Extravagance (prover 5)
Fastidiousness (provers 3, 6, 9)
Multiple specific fears (abandonment, accident, homosexuality, men, sexual assault)
Forgetfulness (provers 3, 4, 5, 8, 9)
Feeling forgotten (provers 8, 9)
Hopelessness (provers 2, 3, 9)
Impatience with children (provers 1, 2, 3, 9)
Indolence (provers 1, 8)
Irresolution (prover 7)
Self-loathing (provers 2, 3)
Memory weakness (provers 3, 7)
Weakness for names (provers 3, 7)
Weakness for words (prover 5)
Mistakes in gender (prover 6), localities (prover 8)
Mistakes about objects (provers 8, 9), names (prover 7)
Self-pity (provers 1, 2, 3, 9)
Reproaching others (prover 9)
Restlessness, sometimes with pain
Sadness (provers 3, 5, 7), before menses (prover 3)
Noise sensitivity (prover 9), high-pitched noise
Stupefaction as if intoxicated (provers 1, 3)
Desire for sympathy (provers 1, 2, 3, 9)
Suicidal thoughts (provers 2, 3)
Rapid thoughts (prover 1)
Weeping/tearful mood (provers 3, 7)
Causeless weeping (prover 7)

Vertigo

Morning vertigo (prover 4)
Light-headedness (prover 6)
Drifting or falling sensation (provers 5, 6)
Falling to left (prover 5)

Head

General:

Dry, flaking scalp (prover 5)

Headache:

Frontal pressure (provers 6, 9)
Dull, gripping sensation (prover 9—like excess caffeine)
Dull occiput (prover 1)
Throbbing above eyes (prover 6)
Pressure temples (prover 5), worse lying down
Before menses (provers 3, 4)

Eyes

Stye right eye
Discharge right eye
Involuntary eyelid opening/closing
Dryness
Difficulty focusing
Blurry when reading (prover 4)
Sensation of bug flying in peripheral sight (prover 7)

Ears

Pain:

Aching
Ringing noises
Cutting pain
Oozing eruption on earlobe

Hearing:

Noises like honey (prover 5)
Stretched sounds (prover 5)

Face

Parotid gland inflammation (prover 1)
Herpetic eruptions on lips (provers 3, 5, 8)
Lower lip herpetic eruptions (provers 5, 8)
Mouth corner eruptions (prover 6)
Forehead eruptions (prover 5—persistent new symptom)
Eyebrow eruptions, painful to touch (prover 5)
Eruption over left eye (prover 5)

Note: Three provers experienced at least six-month herpes relief following the proving.

Mouth

Gum hemorrhage (provers 7, 9)
Saliva in gushes
Profuse salivation
Salivation with mumps (prover 1)
Taste: lemons (prover 2)
Spongy gums (prover 9)
Lower gum line thinness and stinging (prover 5)
Tongue chancre sore (prover 6)
Lip chancre sore (prover 3)
Fetid breath (prover 5)
Lip crack/split (prover 5)
Frothy mucous on waking

Teeth

Toothache with chocolate (prover 4)
General toothache (prover 6)
Right lower teeth pain (prover 7)

Nose

Catarrh (prover 4)
Obstruction (prover 4)
Imagined and real fruit odors, peaches
Imagined sulfur odor
Acute sense of smell (prover 5)

Throat

Sore throat (prover 8)
Sore throat improved with tea (prover 4)
Sore throat with ear tickling (prover 4)
Submandibular left-side pain
Tightness

Expectoration:

Throat mucous, stuck
Greenish-yellow phlegm
Yellow phlegm

Stomach

Pain and gas (provers 3, 5)
Insatiable appetite (prover 3)
Appetite lacking for dinner (prover 3)
Stomach upset improved by cold water (prover 5)
Sharp pain (prover 6)
Pain with belching (provers 5, 7)
Appetite wanting (prover 4)
Spikes/flashes of nausea (prover 8)
Sour eructations (prover 5)

Abdomen

Knot-like pain
Sharp bowel pain
Dull pain
Guilty pain (prover 4—special note)

Back and Neck

Gap sensation in mid-back; as if separated (prover 5)
Nape neck pain (prover 4)
Coccyx pain
Dull, throbbing pain
Neck/shoulder tension
Neck pulling to left

Chest

Mammae/nipple pain in men
Mammae pain before menses (prover 4—new)
Mammae swelling before menses (prover 4—new)
Gas pain, center chest radiating
Constriction pain
Aching pain

Extremities

General:

Awkwardness (provers 2, 3, 5, 7)
Hand awkwardness
Lower limb awkwardness
Foot coldness
Insensibility/numbness (provers 4, 8, 9)
Upper limb numbness (provers 4, 9)
Lower limb numbness
Arm numbness on waking
Foot numbness

Pain:

Joint pain
Shoulder pain when lying on side (prover 7)
Right shoulder pain extending to wrist (prover 7)
Upper extremity aching
Upper extremity aching at night (prover 8)
Shoulder aching
Upper arm aching
Groin cracking pain with walking (prover 6)
Knee lancinating pain
Foot sole soreness
Wrist pinching
Hip throbbing pain
Wrist throbbing
Stiffness

Female Symptoms

Herpetic eruptions (provers 3, 6)
Boil on labia (prover 6)
Increased sexual desire (provers 2, 6, 9)
Masturbation desire (prover 6)
Painful menses/dysmenorrhea (prover 4)
Brown discharge (prover 4—new)
Profuse menses (prover 4—new)
Intermittent menses (provers 4, 9)
Spotting (prover 6)
Lower vaginal region pain (prover 6)
Left ovary pain
Sharp cervix pain (prover 9)
Sharp left ovary pain (prover 4—new)

Male Symptoms

Increased sexual desire
Testicular pain
Testicular pinching with radiation to thigh (right side)
Flaccid penis
Impotence

Perspiration

Night sweats (prover 7)

Rectum

Constipation (provers 4, 5, 7, 9)
Straining required
Absence of urging
Insufficient/incomplete/unsatisfactory evacuation
Excessive smelly flatulence (provers 5, 7)

Stool

Dry
Pasty
Soft
Light brown color
Loose (prover 7)

Respiration

Shortness of breath

Skin

Eruptions (provers 3, 5, 6, 7, 8):

Herpetic eruptions (same provers)
Right upper back boil (prover 6)
Cervical area eruption (prover 5)
Red rash above left axilla after bathing (prover 6)
Flat pink scaly chest rash (prover 6)
Raised red bumps on upper thigh (prover 8)
Hand eczema
Greasy skin (prover 5)

Sleep

Deep soporific sleep (prover 5)
Fetal position, right side (prover 9)
Snoring during nap (prover 9)
Overwhelming sleep desire (prover 1)
Deep unrefreshing sleep (prover 5)
Waking groggy (provers 1, 3)
Early sleeping (prover 5)
Restlessness (prover 7)
Late waking (prover 7)
Sleepiness (prover 6)

Urine

Musty-smelling (prover 6)

Seemingly Cured Symptoms

The proving produced remarkable therapeutic results in several cases:

TMJ of one-year duration disappeared (prover 5)
Rheumatoid arthritis pain of more than ten years disappeared (prover 2)
Multiple cases of herpetic eruption relief lasting at least six months
Mouth dryness before sleep (three-month history before proving) resolved

New Repertory Rubrics for Musca Domestica

The proving identified new rubrics requiring addition to homeopathic repertories:

Mind, dreams, sexual
Mind, dreams, sexual, violent (rape)
Mind, dreams, Mediterranean scene
Mind, dreams, beach
Mind, dreams, homosexual
Mind, dreams, men, gay
Mind, dreams, trolls, crones, etc.
Mind, dreams, corruption
Mind, dreams, decomposition, decay, rotting, etc.
Mind, dreams, toilet, sewer, etc.
Mind, dreams, tunnel
Mind, dreams, boats
Mind, dreams, grass
Mind, delusion scratched by 1000 fingers

Ideas Difficult to Repertorize

Several symptoms resisted standard repertory classification:

Prover #4: Image of picking sores until bleeding appeared just before remedy dosing
Prover #7: Sensation of being inhabited by insect or rodent spirit
Prover #9: Statement “life is a hopeless dump”
Provers 1, 2, 3: Frequent use of excrement language throughout proving
Prover #1: “I feel like I’ve woken from the dead” after mumps; “I feel I’ve gone through metamorphosis”
Prover #1: Kaleidoscopic visual imagery
Provers #9, 10: Paranoia about Black men (undetermined repertory placement)
Multiple provers: Car-related symptoms (mixed keys, locked cars, car going off road)
General: Strange or perverted sexual ideation and dreams throughout provers

Special Prover #5 Symptoms (Not Repertory Items)

Prover #5 demonstrated a constellation of unique experiences beyond standard rubrics:

Delusions and Visions:

Frenzy of hands when washing face
Water on wrist appearing as many eyes
Lint on robe resembling insect or fish egg nest
Hundreds of eyes visible in soap foam
Moving garbage imagery
Surrounded by corruption and decay sensation
Vision of dying in Grand Army during Russian cholera return
Feeling like animal with darting eyes
Dead squirrel with beetles/wasps burrowing into collapsed eyes

Thoughts and Obsessions:

Homophobia with fear/obsession about homosexuality
Seeing “Italian” people and things (Mediterranean focus)
Desire to stay home and protect wife
Fear wife was leaving him
Flinched, expecting wife to hit him
Compulsive shopping needs
Drawn to brackish subway water
Belief remedy was “degrading and decomposing”
Opened random book page about maggots cleaning pearls—believed significant
Thought remedy was about garbage (garbage imagery recurring)

Other Notes:

Wife believed remedy substance was sea worm or fly
Believed remedy was about garbage
Garbage became central obsessive theme

Conclusion

The proving expanded the homeopathic materia medica through careful Hahnemanian methodology. The common house fly, ubiquitous in human habitation, had never been formally proven despite its historical and practical significance. Through structured observation and systematic documentation, Musca domestica emerged as a remedy with distinct physical, mental, and emotional symptomatology.

The authors emphasize that proving participation constitutes “an honorable journey” resulting in heightened awareness and community strengthening, whether participants experience symptomatic reactions or not. They encourage further Hahnemanian provings to continue strengthening the materia medica and homeopathic community as a whole.