Lac caninum — potentised bitch's milk — is the remedy whose complaints will not stay on one side. Boericke: "The keynote symptom is, erratic pains, alternating sides." Kent generalises it absolutely: "The complaints, almost regardless of kind or quality, change sides."
It is an old medicine made new. Clarke traces it to antiquity — "Dioscorides, Rhasis, Pliny, and Sextus recommended it" — and records that "the remedy was revived by Reisig, of New York, who used it successfully in the treatment of diphtheria", after which Bayard and Swan established it; the provings, published by Swan and Berridge, "were made with the 30th and upwards." Kent, who received his stock from Reisig's line, took the milks seriously as a class: "All the milks should be potentized, they are our most excellent remedies."
Its clinical home is the throat — the shifting, glistening sore throat and the diphtheria of the old records — and the female sphere: menses, breasts, milk. Behind these sits a nervous constitution of rare sensitivity and strange imaginations.
This guide profiles it for clinical study from Boericke's Materia Medica, Clarke's Dictionary, Boger's Synoptic Key and Kent's Lectures. The originals can be read in full — Clarke's Lac caninum, Boericke's Lac caninum and Kent's Lac caninum — through Similia's free digital materia medica.
The Lac Caninum Constitutional Type
Kent classes it among the deep remedies: "It is deep and long acting; the provers felt its symptoms for years after the proving was made." Boericke's ground tone is depletion: it "corresponds to a low-vitiated, non-feverish type of sickness", with "great weakness and prostration" and "sinking spells every morning."
Over this weakness lies an extraordinary sensitivity. Kent: "An oversensitive state prevails, a general hyperesthesia of the skin and all parts." Its most famous expression is the intolerance of self-touch — Boger: "Oversensitive; can't have parts, fingers, etc., touch each other"; Clarke: "Cannot bear one part of her body to touch another; must even keep her fingers apart." Kent saw it clinically: "a woman lay in bed for days with the fingers abducted and would go wild if they touched each other."
The imagination is as heightened as the senses. Boger: "Full of imaginations; horrid, of snakes, vermin, as if floating, etc." Yet the patient conceals it all — Kent: "Although the patient has all these strange feelings, yet she goes around all day about her business, and no one knows them unless she confesses them."
One causation stands in Clarke's schema and is easily missed in case-taking: "Result of fall."
Mental and Emotional Picture
Distressing lack of self-worth. Boericke: "Thinks himself of little consequence." Clarke's provers go further: "Thinks she is looked down upon by every one, and feels insulted thereat", and one "woke at daylight, feeling that she was a loathsome, horrible, mass of disease."
Everything she says feels untrue. Kent: "She is impressed with the idea that all she says is not so, thinks everything she says is a lie"; Clarke adds "that all her symptoms are unreal, and the result of a diseased imagination."
Visions and dreams of snakes. Boericke lists "Visions of snakes" and "dreams of snakes." Clarke's prover "imagined she was surrounded by them; was afraid to close her eyes at night for fear of being bitten by a large snake which she imagined was beside the bed."
Every symptom a settled disease. Boger: "Every symptom seems a settled disease." Clarke's fear-list is specific: "of disease; of consumption; of heart disease; of falling downstairs."
Floating. Boericke: "Feels as if walking on air, or of not touching the bed when lying down." Kent refines it: a vertigo "unusually refined; not the vulgar swaying or tossing... as if she were swimming or floating in the air, spirit-like."
Cannot bear to be alone. Clarke: "Cannot bear to be left alone for an instant"; Kent confirms, and contrasts it with Lachesis, whose patient "wants to be alone to indulge the strange fancies."
Despondency with irritability. Boericke: "Despondent; thinks her disease incurable. Attacks of rage." Kent: "Chronic sadness, everything so dark; irritable, ugly, hateful." Add the forgetfulness — "Very forgetful; in writing, makes mistakes" — and Kent's caution that these states lie "on the border-land of insanity or delirium" while the patient still functions: recorded symptomatology for careful professional assessment.
Physical Affinities
The alternation of sides
The grand generality, worth a section of its own. Kent: "The rheumatism is first found in one ankle and then in the other, and then back again to the original site." Headaches, neuralgias, erysipelas, ovarian pains and throats all obey it. Clarke's provings made it doctrine — "an alternation of sides, often very rapid" — and his cured case of eyelid eczema turned on a casual remark that "it often left one side entirely and went to the other and then back again."
Throat
Boericke: "Tonsillitis and diphtheria symptoms change repeatedly from side to side. Shining glazed appearance of deposit, pearly-white or like pure white porcelain." Boger: "THROAT SORE, has glistening patches of china whiteness; or red glistening." Kent's version: "a felt-like exudation, ashy gray or silvery shiny deposit"; "The diphtheritic membrane is also white like silver."
The concomitants are precise: "Painful swallowing; pain extends to ears"; throat "sensitive to touch" externally; worse empty swallowing, "ameliorated by cold or warm drinks" (Kent). And the timing keynote — Boericke: "Sore throat beginning and ending with menses"; Clarke: "these sore throats are very apt to begin and end with the menses."
The diphtheria record runs through every source: Clarke — "It is in diphtheria, both as curative and prophylactic that Lac can. has won its greatest fame"; Kent — "it has also cured paralysis following diphtheria"; Boger — "Diphtheria; paralysis after."
Female sphere
"Menses too early, profuse, flow in gushes" (Boericke). "Breasts swollen; painful before... and better on appearance of menses. Mastitis; worse, least jar." The milk symptoms are a speciality: "Galactorrhœa", and the "decided effect in drying up milk in women who cannot nurse the baby." Boger sets it in capitals — "DRIES UP THE MILK. Scanty milk" — and Kent gives the indication its human setting: "When a mother has lost her infant and it is necessary to dry up the milk, Lac. c. and Puls. are the best remedies for this purpose, when no symptoms are present. They will do it speedily."
The ovaries follow the general law: Kent records "severe pain in the region of the right ovary, ameliorated by the flow of bright red blood", the pains taking alternate sides.
Head and senses
"Pain first one side, then the other" (Boericke), often "perfectly unbearable" (Kent). Two strange cerebral sensations: "Sensation as if brain were alternately contracted and relaxed", and the floating vertigo. Hearing plays tricks — Clarke: "Reverberation of voice as if speaking in a large, empty room"; "Sounds seems very far off." Kent adds the haunted vision: "She sees faces before her in the dark."
Nose
The coryza obeys the alternation: "one nostril stuffed up, the other free; alternate" (Boericke). The deeper record is ozaena — Clarke's cured case had "bloody pus discharged" and "bones of nose sore to pressure", with "alæ nasi and corners of mouth cracked."
Extremities
"Sciatica, right side. Legs feel numb and stiff, cramps in feet. Rheumatic pains in extremities and back, from one side to the other. Pain in arms to fingers. Burning in palms and soles" (Boericke). Kent's rheumatism is "aggravated by motion and heat, ameliorated by cold" — classing it, he notes, with Pulsatilla and Ledum. Boger adds the small but useful "sore heels."
Key Modalities
Worse from:
- Touch and jar — Boger's first aggravations; "Mastitis; worse, least jar"
- During menses — and the throat "< at start and close of menses" (Boger)
- Cold air, wind or drinks (Boger) — the headache from riding in cold wind is better in a warm room (Kent)
- Empty swallowing (Kent)
- After sleep and motion (Clarke: "Rest and lying down > most symptoms; motion <")
- The alternating clock — Boericke: "Worse, morning of one day and in the evening of next"
Better from:
- Open air (Boger)
- Cold and cold drinks — Boericke's general amelioration; Kent's rheumatic pains "ameliorated by cold"
- Warmth for selected pains — Clarke: pains in ankles, forehead and upper jaw were "> by warmth"
- Rest and lying down (Clarke)
The temperature relations split by complaint — rheumatism better cold, cold-wind headache better warmth, throat eased by either cold or warm drinks — a remedy where the modality must be taken per symptom, not per patient.
Keynote Symptoms
- Symptoms alternate sides — throat, ovaries, headache, rheumatism — often returning to the first side
- Sore throat with shining, glazed, pearly-white deposit; pain to the ears on swallowing
- Sore throats beginning and ending with the menses
- Floating sensation — walking on air, not touching the bed when lying
- Visions and dreams of snakes
- Thinks himself of little consequence; every symptom seems a settled disease
- Cannot bear parts of the body to touch each other; fingers kept apart
- Breasts swollen and painful before menses, better when the flow appears; mastitis worse from the least jar
- Galactorrhœa; dries up the milk
- Menses too early, profuse, in gushes
- One nostril stuffed, the other free, alternating
- Worse morning of one day, evening of the next
Clinical Applications
Alternating-sided sore throats and tonsillitis. The signature indication, with the glistening deposit as confirmation.
Diphtheria and its sequelae. The historical fame of the remedy — curative and prophylactic in the old records — and Kent's cured cases of post-diphtheritic paralysis; the classical texts are the source of record here.
Rheumatism that changes sides. Kent's ankle-to-ankle description, better from cold applications.
Breast conditions. Mastitis worse from the least jar; galactorrhoea; drying up the milk when nursing must cease.
Menstrual states. Gushing, profuse, early menses; complaints — throat above all — keyed to the start and close of the flow.
Ozaena. Clarke's cured case, with soreness of the nasal bones and bloody, purulent discharge.
Nervous hypersensitivity states. The floating, snake-visions and self-disparagement cluster, assessed as recorded symptomatology in patients who typically conceal it.
Differential Diagnosis
Lac caninum vs. Lachesis. Clarke: "Lachesis is the nearest analogue" — throat and ovaries, intolerance of touch, even the floating sensation, which Kent notes "belongs to Lach." as well. But Lachesis moves once, "left to right", and is worse after sleep; Lac caninum oscillates, right to left and back again. For the fingers that cannot bear to touch each other, Kent says the state is "difficult to cure outside of Lac can. and Lach."
Lac caninum vs. Pulsatilla. Boger relates the two, and both wander. Pulsatilla's pains shift anywhere in a mild, weepy, thirstless patient; Lac caninum's alternate strictly between sides in an oversensitive, imaginative patient with the self-disparaging delusions. In drying up milk Kent pairs them and assigns Pulsatilla "in the Puls. constitution."
Lac caninum vs. Sepia. Both serve the depleted female patient with despondency. Sepia's picture is stagnation — bearing-down, indifference, dragging exhaustion relieved by vigorous exercise; Lac caninum's is erratic oversensitivity — alternating pains, floating, horrid imaginations and the conviction of being worthless or looked down upon.
Lac caninum vs. Lycopodium. Kent's teaching case: a throat that "commenced on the right and went to the left" suggested Lycopodium, "and Lyc. failed, but when it returned to the right the alternation was noticed and the remedy revealed." Lycopodium travels right to left and stays; a genuine back-and-forth oscillation belongs to Lac caninum.
Repertorisation Tips
These rubrics carry Lac caninum in high grade:
- Generalities; SIDE; alternating sides
- Throat; PAIN; alternating sides
- Throat; MEMBRANE; exudation; shining, pearly-white
- Throat; PAIN; sore; menses, begins and ends with
- Mind; DELUSIONS; snakes, of
- Mind; DELUSIONS; floating in air, of
- Mind; DELUSIONS; despised, is
- Mind; FEAR; disease, of impending
- Chest; MILK; flow of, excessive
- Female; MENSES; profuse; gushing
- Chest; PAIN; Mammæ; jar agg.
- Extremities; PAIN; rheumatic; alternating sides
The alternation itself is the anchor — a strange, rare and peculiar generality that few remedies share — and it outweighs any single local symptom. Confirm with the glistening throat deposit, the menstrual timing, the floating sensation or the snake imagery. Our beginner's guide to repertorisation sets out the anchoring method in more detail.
Deepening Your Study
- Boericke condenses the keynote — erratic pains, alternating sides — with the throat, breast and milk indications and the dose note ("Thirtieth and the highest potencies")
- Boger's Synoptic Key capitalises the alternation and the glistening china-white throat; his General Analysis lists ALTERNATING EFFECTS, FLOATING and GLISTENING among the remedy's grand characteristics
- Kent's Lectures carry the history of the potencies, the fullest account of the alternation and touch-sensitivity, and the milk indications
- Clarke's Dictionary holds the ancient history and Reisig revival, the proving curiosities — snakes, the borrowed nose, the lying feeling — and the Lachesis comparison
You can read all of these side by side for any remedy through Similia's free digital materia medica. To place Lac caninum among its peers, see the guide to the essential polycrest remedies, or read how materia medica and repertory work together in case analysis.
