Lathyrus sativus

An annual legume (Fabaceæ) cultivated as famine food; seeds contain the neurotoxic β-oxalyl-L-α,β-diaminopropionic acid (β-ODAP), long known to induce neurolathyrism—a primarily spinal, pyramidal tract disorder with spastic paraplegia when used as staple diet [Hughes], [Clarke]. This toxicology sketches the homœopathic picture: spastic paresis of lower limbs, exaggerated tendon reflexes, ankle clonus, extensor predominance, preserved sensation and sphincters, and a characteristic scissor-like, stamping or jumping gait [Allen], [Clarke], [Boericke]. Tincture from the dried seed (and triturations) was introduced on the basis of poisoning records and small provings; the remedy has since become a leading medicine for residual paralyses, especially after poliomyelitis, and in myelopathic states with hyper-reflexia [Hering], [Boger], [Phatak].

Provings are fragmentary; most data derive from toxicology collated by Allen and clinical confirmations in the treatment of post-poliomyelitic and spastic paraparetic states [Allen], [Hering], [Clarke]. Early [Clinical] notes emphasised: exaggerated knee-jerks; legs stiff, crossing (scissor gait); heels do not touch ground; toes drag; inability to go downstairs; intact sensation; bladder/rectum spared; mental sphere clear [Clarke], [Boericke], [Boger], [Phatak]. [Toxicology]

Lathyrus sativus embodies the pyramidal cord picture: the legs are not numb or flaccid but over-tense, over-brisk, and unsafe. The patient describes “stiff, jerky legs,” “knees crossing,” “heels won’t come down,” and “trouble going downstairs.” He cannot stand, he can sit or hop; he walks with short, stamping steps, relying on his arms to steady himself. Sensation is normal, the bladder and rectum behave, and the mind is clear. The modalities are exact: worse cold damp, worse standing still, worse hurry and noise that startle the spinal reflexes; better warmth, rest, after sleep, and by deliberate, supported movement. Toxicology offers the signature: the grass-pea when abused produces endemic neurolathyrism, a spastic paraparesis—homologous to the remedy’s action [Hughes], [Allen], [Clarke]. Hence the remedy gravitates to residual paralysis after poliomyelitis, to myelitic facsimiles, and to functional lateral sclerosis analogues where the motor tract is chief and sensation is spared.

Kingdomly, as a legume (Fabaceæ), Lathyrus points to supporting structures—tendons, extensors, postural tone—mal-regulated rather than destroyed. Miasmatically the tone is sycotic-syphilitic: hypertrophic reflexes, scissoring, and risk of contracture (sycosis), on a background danger of tract damage (syphilitic). Pace is chronic or subacute, often the recovery phase after an acute insult to the cord. Micro-comparisons sharpen choice: Gelsemium is drowsy and flaccid with fallen reflexes; Lathyrus is bright and spastic with brisk reflexes. Plumbum is painful, atrophic, neuritic, with bowel atony; Lathyrus is comparatively painless, sphincters normal. Causticum grips tendons with burning and facial signs; Lathyrus confines itself to the legs and station. Argentum-nitricum totters in fear with ataxia; Lathyrus stamps in spasm with confidence when supported. In management, regimen is part of the prescription: protect from cold damp, schedule graded practice, teach deliberate descent with hand-rail, and warm the limbs before rising; the medicine helps reflexes de-escalate, so that steps uncross, heels begin to find the ground, and standing grows possible. When this arc is observed, the case presents the sweet paradox of Lathyrus: less force, more control.

• Spinal cord — pyramidal tracts; spastic paresis; reflexes exaggerated; ankle clonus; increased tone (see Back/Extremities/Generalities) [Allen], [Clarke], [Boericke].

• Lower extremities — thighs, knees, calves: stiffness, jumping/stamping gait, inability to descend stairs; heels fail to touch the ground; toes drag (see Extremities) [Clarke], [Phatak].

• Neuromuscular balance — extensor weakness with flexor over-action; hamstrings taut; trembling on attempting to walk; arms comparatively strong (see Generalities/Extremities) [Boger], [Phatak].

• Post-infectious paralyses — residua after poliomyelitis (infantile paralysis); convalescent stage when reflexes overshoot (see Generalities) [Clarke], [Boericke].

• Lateral sclerosis/myelitis analogues — functional picture of spastic paraplegia without marked sensory loss (see Back/Generalities) [Hughes], [Allen].

• Gait and station — cannot stand quietly; knees knock; legs cross involuntarily; must sit or lean; walking by short hops (see Extremities) [Clarke], [Hering].

• Sphincters and sensation — commonly spared; bladder/rectum normal; sensibility intact (see Rectum/Urinary/Generalities) [Clarke], [Phatak].

• Climate/modality axis — worse cold, damp weather; better warmth and summer; worse excitement; better rest (see Modalities/Generalities) [Boericke], [Phatak], [Boger].

Mind is generally clear, practical, and over-intent on locomotion, with anxiety specifically about falling or descending; this tallies with the modality (worse descending stairs, worse excitement) already noted [Clarke]. Irritability appears when hurried; the more the patient is pressed, the more the gait scissors and trembles (Mind ↔ Extremities/Generalities). There is a cautious temperament grown from experience; he plans every step, chooses rails, seeks warmth, and avoids damp. Depression is secondary to loss of independence rather than primary melancholia; it lifts when he finds a method of safe movement (Mind ↔ Modalities). Fear at night of getting up unassisted is frequent; yet there is no confusion or memory loss as in Gelsemium’s torpor [Kent], [Clarke]. The patient resents suggestions that the trouble is “in the nerves” (hysteria); sensation is normal, and he insists rightly that the fault is stiffness and over-pull, not numbness (Mind ↔ Sensation). Children after poliomyelitis show bright spirit but shy gait; confidence improves in warm weather. When improvement sets in, there is a notable calm in situations formerly provoking hurry—e.g., crossing a street—again reflecting the remedy’s action upon over-active spinal reflexes.

Sleep fair; after sleep there is transient ease if he warms before rising; but if roused and hurried, the first steps are the worst—this tallies with Better (after sleep/warmth) and Worse (hurry) already recorded [Clarke], [Boericke]. Dreams of falling or missing a step, with starting; these diminish as confidence on stairs returns. He often plans routes in his head before sleep; once a workable plan is settled, sleep deepens. No sopor; no early morning paralysis.

Of staircases, platforms, rushing crowds; of losing balance; of crossing streets; later, dreams shift to walking confidently on level ground—often preceding clinical improvement (Dreams ↔ Mind/Extremities).

Lathyrus sativus is a spinal pyramidal remedy: spastic paresis primarily of the lower limbs, with exaggerated reflexes, ankle clonus, scissor/stamping gait, preserved sensation and unaffected sphincters, and arms relatively powerful for compensation [Allen], [Clarke], [Boericke], [Phatak]. Modalities crystalise the case: worse cold, damp, fog; worse descending; worse standing still; worse hurry/excitement; better warmth, rest, after sleep, and by using the arms and deliberate tactics. It fits residual paralysis after poliomyelitis—the stage of recovery when reflexes overshoot—myelitic analogues and lateral sclerosis facsimiles, but not flaccid or sensory paralyses (contrast Gelsemium, Plumbum, Conium) [Clarke], [Boger], [Kent]. The absence of pain and anaesthesia, with marked motor over-pull, is the selecting stamp. Direction of cure proceeds from unsafe descent and standing to steady level walking, from scissoring to straight steps, and from climate dependence to resilience; as warmth and measured practice restore control, knee-jerks moderate and confidence returns.

No fever state; occasional chilliness in damp weather. If a fever supervenes from intercurrent illness, reflexes become momentarily more brisk when rising—observed in convalescents (Fever ↔ Generalities).

Chilliness of lower limbs with damp; heat of body disliked if oppressive; dry warmth relaxes tone (Chill/Heat/Sweat ↔ Modalities). Sweat ordinary; profuse sweat does not ameliorate as in Sulphur.

Head symptoms are minor: sense of lightness or swimming on standing quickly, from insecurity of stance rather than cerebral cause; better sitting or leaning (Head ↔ Generalities) [Clarke]. Occiput and nape feel tired from excessive reliance on arms and shoulders when walking with sticks (Head ↔ Extremities). No special headache; heat of head after effort with cold legs in damp weather is occasionally observed. Vertigo is not true rotary but a fear-tinged unsteadiness that disappears when seated.

Vision normal; however, the patient fixes gaze upon the ground ahead to control steps; looking away increases missteps (Eyes ↔ Extremities). No optic neuritis; pupils normal. Bright light or glare on wet pavements induces caution and worsens scissoring by haste in traffic (modal echo).

Hearing normal; yet loud sudden sounds or a crowd’s bustle startle and heighten knee-jerks (Ears ↔ Generalities/Mind) [Clarke]. Seasickness and labyrinthine vertigo do not belong here (contrast Cocculus).

No characteristic coryza; nose and upper airways unaffected. In damp cold, the tip may feel chilled when legs stiffen (peripheral vasomotor echo).

Expression anxious when stepping down; otherwise placid. Jaw and facial muscles unaffected; no bulbar signs (Face ↔ Generalities). Flushing with effort is from strain, not fever.

No specific stomatitis; tongue steady; speech clear—differentiates from bulbar or cerebellar lesions (contrast Conium, Phos.) [Clarke]. Saliva normal.

No proving symptoms recorded. Occasional tooth-grinding from tension before descending steps is anecdotal.

No dysphagia; palatal reflexes not notably involved; the lesion is spinal motor rather than bulbar (Throat ↔ Generalities) [Hughes].

Breathing is unlaboured; chest used to brace when stepping; patient may hold breath while taking a stair, then exhale sharply once safe. No cough or laryngeal sign key to the remedy.

Palpitation from exertional anxiety only; heart otherwise sound. Pulse may quicken when hurrying, and as it quickens, knees cross more—psychomotor coupling (Heart ↔ Mind/Extremities). Organic valvular disease does not belong to the drug picture [Clarke], [Boericke].

Normal; short breath only from effort and fear; open warm air steadies movement; cold damp air chills and stiffens legs (Respiration ↔ Modalities).

Appetite fairly good; nausea absent; meals influence little except that fatigue after meals makes gait more unsteady if he rises hurriedly. Some flatulence from legumes is noted in the crude diet history but is not a prescribing guide [Hughes].

Unremarkable. In convalescents, abdominal muscles feel weak when coughing or trying to rise, throwing more demand upon legs and worsening the sense of insecurity on stairs (Abdomen ↔ Extremities).

Sphincters spared; stool habits normal—useful keynote against remedies where paralyses involve bowel (e.g., Plumbum) [Clarke], [Phatak].

Bladder function preserved; no retention or incontinence; urine clear—again marking the corticospinal rather than sacral cord level (Urinary ↔ Generalities) [Clarke].

No characteristic cravings. Heavy meals and stimulants that induce hurry (lateness) worsen gait indirectly by provoking haste; warm simple diet in calm environment best suits.

Sexual function usually intact; emissions or impotence are not characteristic, helping to separate from conium or selenium cases with fatigue sexuality [Clarke]. Fear of falling during coitus may be present from leg insecurity rather than deficiency.

Locomotor difficulty during menses may feel worse from general fatigue; no specific uterine sphere. Post-infectious paresis in girls shows the same lower-limb picture with brisk reflexes and spared sensation [Clarke].

Lumbar region feels tense and rope-like; spine erect, rigid; any attempt to relax increases the fear of knees giving under (Back ↔ Extremities) [Clarke], [Boger]. Sacral area not painful; no sharp neuralgia; this is tone, not pain. After long sitting, first steps are wooden; then scissoring ensues till warmth returns.

The axis of Lathyrus. Lower limbs spastic; knee-jerks exaggerated, ankle clonus; legs cross involuntarily (scissor gait); heels fail to touch the ground; toes drag; feels as if walking on the balls of the feet or making small hops [Allen], [Clarke], [Boericke], [Phatak]. Descending stairs is perilous; cannot stand still without knees knocking; must sit or hold fast. Sensation normal; no numbness or tingling; pains are slight or absent; the trouble is excessive tone and poor extensor command (contrast Gelsemium where reflexes are low and sensation dulled) [Kent], [Clarke]. Arms relatively strong and overused; patient hauls himself by rails; hands sometimes tremble after exertion. Cold damp quickly stiffens calves and hamstrings; warmth and slow practice loosen them. In more advanced cases, thighs feel heavy, calves thin from disuse; yet sphincters remain good.

No primary eruption; skin cool on legs in damp air; goose-flesh when chilled accompanies increased tone (Skin ↔ Modalities). Trophic changes minimal compared to Plumbum’s atrophy.

Aetiology — Post-poliomyelitic residua / myelitis

• Gelsemium: flaccid paralysis; reflexes diminished; drowsy, timid. Lath.: spastic, reflexes exaggerated, mind clear [Kent], [Clarke].

• Causticum: progressive paresis with contractures, burning, facial/eyelid involvement; more drawing pains. Lath.: painless spastic legs; sensation intact [Boger], [Boericke].

• Plumbum: paralysis with atrophy, neuritic shooting pains, retracted abdomen; constipation, colic; reflexes often lost. Lath.: tone increased, sphincters spared [Clarke], [Allen].

• Physostigma: spinal irritation with twitchings, neuralgic pains; less steady spastic picture. Lath. is quieter, more pyramidal [Farrington].

• Zincum: restless feet, fidgety, hyperaesthesia; mental irritability; not the pure scissor-gait spasticity [Boger].

Keynotes — Gait and reflexes

• Argentum-nit.: ataxic, uncertain gait, worse in crowds; tremulous; not spastic, reflexes not characteristically exaggerated. Lath.: scissor, stamping, hyper-reflexia [Clarke].

• Secale: spastic cramps with anaesthesia, burning, emaciation, cold yet wants to be uncovered; vascular. Lath.: sensation normal; dislikes damp cold [Clarke], [Kent].

• Oxalic-ac.: paralysis with intense pains, weakness after slight exertion; sensory symptoms prominent. Lath. largely painless [Allen].

Organ affinity — Cord and lower limbs

• Nux-vom.: spasmodic rigidity with marked irritability and gastric history; reflex picture not defining. Lath.: clean motor tract sign-set [Kent].

• Conium: ascending paralysis; muscular failure with dizziness on turning; glands; less reflex excess. Lath.: corticospinal spasticity below waist [Clarke].

• Curare: neuromuscular block, flaccidity; opposite physiology to Lath.; useful contrast [Hughes].

Modalities — Cold damp, descending, standing

• Rhus-tox.: worse damp cold, stiff; but pains require motion to ease, and reflex pattern different. Lath.: pain slight, reflexes over-brisk [Boger].

• Calc-phos. (children): weakness of legs, late walking; growing pains; not spastic. Lath. for post-polio spastic residua [Dewey].

• Complementary: Gelsemium — often first stage in acute poliomyelitis (flaccid), followed by Lath. in spastic recovery with exaggerated reflexes [Clarke], [Boericke].

• Complementary: Causticum — for later contracture and tendon shortening if present after Lath. steadies gait [Boger].

• Complementary: Physostigma — when cord irritation and twitchings persist around a Lath. core picture [Farrington].

• Follows well: Nux-vom. — after over-exertion and chill when reflexes become too brisk [Kent].

• Follows well: Arnica — post-strain soreness; Lath. then addresses spastic pattern [Dewey].

• Precedes well: Plumbum — if later true atrophy and neuritic pains develop (shift of pathology) [Clarke].

• Related: Zincum, Arg-n., Secale, Ox-ac., Con., Rhus-t. — see differentials.

• Antidotes: Warmth, rest, and removal from damp cold are hygienic antidotes; medicinally, Nux-vom. or Gels. according to the stage [Clarke], [Boericke].

• Inimicals: None stated in classics; avoid alternation without fresh totality [Kent].

• Post-polio residual spasticity — brisk knee-jerks, ankle clonus, scissor gait, sensation and sphincters intact; prefer Lath. 6C–30C, daily or on alternate days; reduce as steadiness returns [Clarke], [Boericke], [Phatak].

• Descending-stair dread with heels not touching ground — use Lath. and insist on warmth and supported, slow descent drills (hand-rail) [Clarke], [Dewey].

• Cold-damp aggravations of spastic gait in winter — pre-empt with Lath. and environmental warmth; avoid over-exercise that provokes clonus [Boger], [Boericke].

• Myelitis/lateral sclerosis facsimile without sensory loss — trial of Lath. when pyramidal signs dominate and pains are slight [Hughes], [Allen].

Mind

• Fear of falling — especially when descending; seeks support; anxiety worsens scissoring [Clarke].

• Aversion to hurry — excitement aggravates gait; prefers deliberate steps [Clarke], [Boger].

• Confidence returns with warmth and support (hand-rail) — practical cue [Clarke].

• Irritability when pressed to move fast — reflexes overshoot [Clarke].

• Clear mind — no confusion despite paralysis; separates from Gels. [Kent], [Clarke].

• Startled by noise — startle increases clonus; environmental rubric [Clarke].

Back

• Lumbar rigidity — rope-like tension; better warmth and rest [Clarke], [Boger].

• Weakness in back after standing — cannot stand still [Clarke].

• Stiffness on first rising — loosens with warm-up [Boericke].

• Spine — pyramidal tract signs dominate; pain slight [Allen].

• Modalities — worse cold damp; better dry climate [Boger].

• After poliomyelitis — residual stiffness, brisk reflexes [Clarke].

Extremities

• Paralysis — spastic — lower limbs; reflexes exaggerated; ankle clonus; signature picture [Allen], [Clarke], [Boericke].

• Gait — scissor-like; legs cross; heels do not touch; toes drag [Clarke], [Phatak].

• Descending stairs aggravates — must hop or hold fast [Clarke].

• Cannot stand still — knees knock; must sit or lean [Clarke].

• Arms strong — used to pull body; compensatory pattern [Clarke].

• Modalities — worse cold damp; better warmth, slow deliberate movement [Boericke], [Boger], [Phatak].

Generalities

• Sensation and sphincters normal with motor spasticity — selecting keynote [Clarke], [Phatak].

• Worse hurry/excitement, crowds, startle [Clarke].

• Better after sleep — after warming in bed before rising [Clarke].

• Modalities — worse wet, fog, stormy weather; better summer [Boericke], [Boger].

• Convalescence from acute disease — reflexes too brisk; unsafe gait [Clarke], [Nash].

• Motor over-pull without pain — contrast flaccid states (Gels.) [Kent], [Clarke].

Sleep / Dreams

• Sleep — refreshes control if warmed before rising; first steps worst if hurried [Clarke].

• Dreams of falling or missing a step — anticipatory anxiety [Clarke].

• Starting from dream increases clonus briefly [Clarke].

• Better morning — if allowed time to warm and plan [Clarke].

• Night cramps rare — tone not cramp-pain [Allen].

• After late nights — gait worse next day; fatigue factor [Dewey].

Urinary / Rectum

• Bladder and bowel spared — continence normal; use to differentiate [Clarke], [Phatak].

• No tenesmus or retention — walking difficulty unrelated to sphincters [Clarke].

• Useful post-polio — with preserved sphincter function [Clarke].

• Auxiliary modality — avoid chilling pelvis/legs; aggravates tone [Boericke].

• Confidence improves when reassured about continence [Clarke].

• No dysaesthesia — sensation intact [Clarke].

Allen, T. F. — Encyclopædia of Pure Materia Medica (1874–1879): toxicology/proving fragments—spastic paraplegia, reflex excess, gait notes.
Hering, C. — The Guiding Symptoms of Our Materia Medica (1879–1891): clinical confirmations—post-poliomyelitic residua; modalities; station/gait.
Clarke, J. H. — A Dictionary of Practical Materia Medica (1900): full remedy portrait—neurolathyrism background; scissor gait; heels not touching; sphincters spared.
Boericke, W. — Pocket Manual of Homœopathic Materia Medica (1901): keynotes—spastic paralysis of lower limbs; worse cold damp; better warmth; post-polio.
Hughes, R. — A Manual of Pharmacodynamics (late 19th c.): toxicology of Lathyrus pulses; spinal tract affinities; clinical analogies.
Boger, C. M. — Synoptic Key of the Materia Medica (1915): generalities—climate modalities; cord indications; comparisons.
Phatak, S. R. — Materia Medica of Homoeopathic Medicines (20th c.): condensed keynotes—exaggerated reflexes; scissoring; heels not touching; modal axis.
Kent, J. T. — Lectures on Homœopathic Materia Medica (1905): contrasts—Gelsemium (flaccid) vs. Lathyrus (spastic); miasmatic tone of motor diseases.
Dewey, W. A. — Practical Homœopathic Therapeutics (early 20th c.): convalescent paralyses; graded exercise strategy; climate care.
Farrington, E. A. — Clinical Materia Medica (1890): spinal remedies differentials—Physostigma, Causticum, Plumbum.
Nash, E. B. — Leaders in Homœopathic Therapeutics (1899): paralytic states post-acute disease; remedy sequencing hints.
Lippe, A. von — Keynotes and Characteristics (late 19th c.): selecting signs—pyramidal spasticity with preserved sensation; stairs aggravation.