The Carbon

“Dull pain in the renal region” with the characteristic urine has led to the use of benzoic acid in renal colic, renal gravel; moreover in bladder catarrh in which the great urge to void occurs as a further indication.

The cardiac symptom “pain in the cardiac region, severe palpitation, worse at night, sensation of weakness in the precor- dium, morbid unrest in the chest, heart beat intermits” has also drawn benzoic acid into the domain of rheumatism alternating with cardiac affections.

It is always characteristic of benzoic acid when the pains wander from one place to another, when they vanish from the joints and extremities, then involve internal organs and reversely when the symptoms reappear in the joints with the improvement of the cardiac `complaints, and when the urine periodically alters in regard to its amount, color, specific gravity and odor in relation to the general symptoms of sleep, psyche, headache, and the urine is striking through its odor.

In conjunction with the rheumatic diathesis it should also be mentioned that benzoic acid has been successful in several cases of ganglion on the wrist, internally D 6, and externally 0.2 Acid benz, and 30.0 glycerin cerate. 579

The use of benzoic acid as an :expectorant” is obviously taken over from the formerly frequent use in school medicine. The itching and burning in the throat especially from inhalation promotes the cough and expectoration, therefore the use in bronchitis and asthma, but which has however become more or less relinquished. In homoeopathy this trend of action has not won any great significance, yet there is cited an asthmatic state in reciprocation with rheumatism.

The skin symptoms of benzoic acid are regarded strikingly less in homoeopathy, just as with salicylic acid. They are noted in the provings on the healthy as itching and red patches, but as untoward actions in the form of maculo-papular eruptions and diffuse, itching erythems with red flat nodules at the border.

SUMMARY ——- Chief Trend:

Rheumatic-gouty diathesis.

Change of joint pains: alternation with general complaints, with cardiac or urinary symptoms. Variable state of the urine. Offensive urine “like horse’s urine.” Pyelitis with lithiasis.

(Throat inflammations, cardiac complaints and gastro-intestinal catarrh in association or alternation with rheumatic complaints.)

Guiding Symptoms:

Offensive urine.

Alternation of complaints.

Pain in the Achilles tendon.


Worse from the use of wine; from cold and change of weather; from movement (but headache worse at rest).


The potencies from D 1-D 6 are usual.


Picric acid is a strong acid in watery solution and in its salts. As a protein precipitating agent it is well known from the use of Esbach’s reagent. The absorption of picric acid occurs from the skin, mucous membranes and wound surfaces, which become inflamed on prolonged contact with the remedy; the excretion occurs principally through the urine which is colored an orange yellow, red and by standing in the air to brown black by reduction to the poisonous picramic acid. During the war the picric acid, widely used in the preparation of explosives, was also taken to produce pseudo-icterus since 0.3-1 grams color the mucous membranes, skin and sclera yellow. This has nothing to do with the liver and bile passages.

Upon the coagulation of protein depends the employment of dilute solutions or ointments with picric acid in burns of the first or second degree. However resorptive actions can appear here. Poisoning with large doses produces nephritis, strangury and even anuria. Whether a destruction of the blood occurs with picric acid is doubtful; in any case according to Lewin, methemoglobin cannot be found in the blood, though it is typical for nitrobenzol

(= mirbaneol and dinitrobenzol which is used in the preparation of roburite). After the absorption of picric acid erythema or eczemiform eruptions develop on the skin. The occasional inflammations on the conjunctiva, the mucous membranes of the nose and the digestive canal have nothing typical. After single large doses there appears slowing of the pulse, with prolonged toxic action and intermittent fever.

The important nervous manifestations are mentioned only in general in toxicology; heaviness of the head, headache, vertigo, delirium, prostration, more rarely spasms and many times a sciatica.


The nerve actions of picric acid were first recognized through the intestinal provings on the healthy and were first utilized there. The provings are: 1. Parisel: De l’acide picrique, These, Paris, 1868.

2. Couch: N.Y.J. of Hom., vol. 2, p. 149, 1874.

3. Jones: Allen’s Encyclopedia, vol. VI, p. 519.


One may be doubtful whether this remedy stands nearer the nitrates such as glonoin or the phenol derivatives such as benzoic acid and salicylic acid. But the medicinal trend in acidum picrinicum goes strongly to the central nervous system so that the similarity with salicylate actions on certain nerve centers seems to justify the inclusion in this direction. A glonoin-like headache indeed appears with picric acid nevertheless the vascular action is subordinate to those on the nerve centers of the spinal cord, the medulla, the cerebellum and cerebrum.

The chief field for acidum picrinicum is the severe nervous exhaustion, so severe that it permits one to think of a transition to organic alterations of the central nervous system. Mental work, reading and writing decidedly exhaust, thinking can no longer be concentrated. It can proceed to a complete loss of energy and mental power. Headaches “up to bursting” begin in the occiput and extend foreward to the eyes; they are relieved y tightly binding the head and are worse from movement, from any effort, from dazzling light, from summer heat, in warm rooms, better in the fresh air and on lying down.

But the pains also extend over the neek to the back along the vertebral column and here the syndrome is characteristic and one which played a great role in older medicine as “spinal irritation” a burning and sensation of heat along the vertebra with extreme paralytic-like weakness in the back and in the legs, numbness and sensations of tenseness in various places, particularly in the legs and feet. It is hard to keep the feet warm. Also in partial hyperirritability syndromes as writer’s cramp, picric acid has been employed with good result. After exhausting diseases and mental over-exertion, but particularly in sexual hyperexcitability and states of weakness this picture of a severe neurasthenia is a good indication for acidum picrinicum. Vertigo and ear noises recall those of salicylic and benzoic acid.

The spinal cord for the sexual functions are especially involved; sexual weakness with seminal emissions, spermatorrhoea, states of irritation and priapism from organic spinal cord diseases and finally impotence; in women, pruritis vulvae before the menses. A clinical connection exists to prostatic hypertrophy and for this purpose ferrum picrinicum is usually employed. Dribbling urination and nocturnal urgency are the symptoms. Perhaps the action is to be placed in a series with that on the kideney and urinary passage in general, because in addition to nephritis, strangury is also observed in poisoning. In subacute nephritis with many renal elements and scanty, dark urine one may use picric acid when the exhaustion is particulary outstanding.

In organic nervous diseases as facial paralysis and paralysis agitans, zincum picrinicum is preferred, in prostatic hypertrophy ferrum picrinicum.

SUMMARY ——- Indications: ———— Severe nervous states of exhaustion with “spinal irritation” and states of sexual hyperexcitability;transition to organic disturbances. Nephritis; prostatic hypertrophy.

Modalities: ———- Worse from mental effort, from sun’s heat, better in cold air. Headache better from firmly binding the head.


The usual dose is the D 6.


Hydrocyanic acid, HCN, is known as a poison of rapid action. And still it occurs physiologically fairly often in the plants of different families, usually Rosacea, and particulary in the form of so-called cyanogenous glycosides, for example as amygdalin. In cherries, plums, peaches, apricots, in phaseolus lunata and linum usitatissimum, the content has not obtained medicinal significance, in bitter almonds only a little, but in prunus laurocerasus, crataegus oxyacantha, sambucus nigra, the hydrocyanic acid probably participates in the medicinal effect. The cyanogen containing glucosides in plant metabolism are sugar reserves; through ferments as emulsin which appears in the same plants, the sugar is liberated (for example from amygdalin, hydrocyanic acid, oil of bitter almonds and sugar develops).More- over these glucosides are probably steps in the formation of amino acids in the plants. (The CN2 stands very near to oxalic acid; it is its nitrile and develops from ammonium oxalate by heating with dehydrating agents.) In animals, hydrocyanic acid appears in the glands of certain centipedes. So far as it develops in the metabolism of man, it is detoxified through compounds with sulphur as the thiocyanates (CNS).


The almost lightning-like course of poisoning with HCN or KCN (from which HCN is easily liberated by CO2) shows the extraordinary capacity for penetration in the organism to the vital centers, the respiratory center becoming paralyzed. But the symptoms also diminish just as rapidly as they occur, when the excretionof HCN occurs sufficiently rapidly, and here chiefly through the respiratory passages. In slower poisoning with smaller doses the respiratory and vasomotor center is first stimulated, respiration deepened, cardiac activity slowed, the blood pressure rises, then follows sudden falling of the blood pressure, and respiration ceases; the cardiac action remains unaltered for a relatively long time. In addition the action proceeds on the cell respiration, the respiratiory ferments unable to exert their catalytic activity, the oxygen of the blood cannot be taken by the cells, and the blood remains arterial. According to O. Warburg the iron-containing respiration ferment is poisoned; it is changed into a complex iron compound which is unsuitable for surface catalysis.

The first signs of inhalation of hydrocyanic acid are irritative manifestations in the throat and larynx, burning in the tongue, redness of the mucous membranes, then restlessness and anxiety, headache, nausea and a desire to vomit. Slowing of the pulse and respiration with oppression and constriction of the cardiac region and in the throat, dyspnoea and convulsive breathing (short inspiration and long exhalation) pass over into tonic clonic spasms which can increase up to tetanus and loss of consciousness. Then suddenly the asphyxial stage sets in with falling of blood pressure and ends in respiratory paralysis. After recovery from the poisoning at times there is a persistent weakness in the muscles and the heart.

The alkali cyanides act because of the hydrocyanic acid set free in the stomach, although more gradually according to the amount of HCN liberated. Moreover local corrosive actions occur from the strongly alkaline salts.


Chemically the CN compound behaves entirely like a halogen. The first affinity for the mucous membranes of the upper respiratory passages is entirely similar to that of iodine. Formerly the hydrocyanic acid-containing preparations as aqua amygdalarum amararum were used for the relief of cough, although now they are regarded chiefly as correctives. Heavy metal compounds as cyanide of mercury, Hg (CN)2, are used in homoeopathy much like the corresponding iodine compounds. Hydrocyanic acid itself however through its rapid capacity for the character of carbon compounds so that its considerations at this place seems logical. Outside of numerous descriptions of poisoning, intentional provings of hydrocyanic acid are found:

1. Jorg: Materialien zu einer kunft. Heilmitell., Leip-zig, Bd. 1, S. 82, u. 118, 1825.

2. Hartlaub u. Trinks: Reine A.M.L., Bd. 1, S. 127. 3. Preyer: Die Blausaure, Bonn. 1870.


According to its severe and sudden method of action acidum hydrocyanicum is a remedy for attacks. Convulsive states of a general type, as epileptic, tetanic, and uremic are said to experience transient improvement of the attack from the remedy. But since the epilepsy which has a lightning-like seizure is described as the type suitable for the drug and acidum hydrocyanicum comes into consideration only for the attack and nothing known of a lasting effect on the disease, this use must be rare. The spasm should involve particularly the neck, facial and the jaw muscles.

Acidum hydrocyanicum is more successful in partial spasms which precede paralysis or are associated with it. As with other remedies with spasma such as cuprum, the symptom “drinks roll audibly through the esophagus” refers to spasm of the esophagus. In spasm of the diaphragm acidum hydrocyanicum in the D 6 has proven useful. The initial symptom of scratching in the throat and the larynx provoking dry spasmodic tickling cough has been relieved by acidum hydrocyanicum, in the tuberculous form as well as others. Sensation of constriction in the throat or in the chest and spasm in the respiratory passages, laryngismus and spasmodic cough, with the most severe dyspnoea and cyanosis, precordial anxiety and ice cold skin are the signs of impending respiratory and vasomotor paralysis in which acidum hydrocyanicum is one of the most important remedies for the moment. The remedy is also recommended in cholera when vomiting and diarrhoea cease and col- lapse appears. Sudden weakness belongs to the picture in general. The mental state is anxious as long as confusion or loss of consciousness does not prevail. The headaches are severe and numbing.If, immediately after an apoplexy, the vital centers of the medulla are threatened, one should think of acidum hydrocyanicum. Involuntary stools and urine often appear in the HCN poisoning.

A sensation of warmth, nausea and vomiting which relieves is reported of the stomach; moreover (without point of departure from the provings)a feeling of emptiness in the epigastrium and pain in the empty stomach. The occasional use of HCN containing remedies in nausea and vomiting, gastric pain is traced back to the local anesthetizing action of HCN. Still even in this field the vagal spasm underlies the special influence of acidum hydrocyanicum.


Rapid and short acting agent.

Chief Trends:

Convulsive states, epileptic, uremic, tetanic attacks (palliative) Spasm of esophagus, “drinks roll audibly through the esophagus”; diaphragmatic spasm, sensation of constriction. Scratching in the throat with spasmodic cough. Laryngismus.

Transition or collapse. Precordial anxiety. Cyanosis and icy coldness.

DOSE The D 6 is the common preparation.


Oxalic acid COOH. COOH (or sorrel acid because it is found in large amounts in the wood sorrel, oxalis acetosella) occurs as the calcium salt in many green plants, for example, sorrel, rhubarb and spinach. The absorption from the plants depends upon how much calcium is simultaneously present in the intestine. Because calcium oxalate is not absorbed from the intestine. The greatest part is destroyed by intestinal bacteria and burned to CO2 and H2O. But there are also bacteria in the intestine which can form oxalates from the foods (bacterium oxalatigenum). The fungus, aspergillus niger, can form oxalic acid out of carbohydrates. While oxalic acid in the test tube is easily burned by oxidizing materials, it cannot be split and burned in intermediate metabolism. In the human urine it appears normally in amounts of 15-20 mg. But it need not be precipitated in the form of the well-known crystals of the sediment as calcium oxalate but may also be dissolved. This depends upon the colloidal state of the urine. A small amount of oxalic acid will also be formed endogenously in the animal body and indeed probably in the splitting of glycocoll 580 from connective tissue. By feeding limes the oxalic acid in the urine can be increased.

The formation of oxalate concretions in the urinary passages depends upon many other physical and chemical conditions outside of the quantity of oxalic acid introduced with the plants. The indestructible calcium salt causes no peculiar toxic manifestations but only an irritation of the urinary passages which is associated with an oxaluria.


As is generally known most poisonings occur from potassium oxalate, COOK.COOH. The corrosive action on the gastro-intestinal canal is not different from that of the mineral acids. The prolonged vomiting may be bloody, the diarrhoea also; esophageal distress and radiating pains in the epigastrium are accompanied by precordial anxiety, slowing of the pulse, dyspnoea, twitching of the muscles, lassitude and vertigo. In other cases the resorptive toxic effects appear very rapidly into the foreground; fainting, loss of consciousness and collapse; in longer delayed poisoning there is crawling and numbness in the extremities and headache. Urinary complaints and strangury are associated with the excretion of oxalates, but pain in the kidney region, nephritis with oliguria or anuria, hemoglobinuria and other severe results also occur. In these cases the kidneys are infarcted by oxalate concretions.

Poisoning with oxalic acid its salts is often explained as a calcium precipitation or deprivation exactly as the poisoning with other calcium precipitating acids, for example the related citric acid. The arrest of coagulation of the blood by alkali oxalates and citrates through removal of calcium ions is known and indeed used for many investigations (for example, the sedimentation velocity). In the severe poisonings the muscle contractions, the cardiac damage, perhaps also the nerve actions, signify simply a calcium precipitation process. 581 And for the flooding with large amounts of oxalic acid, the calcium salt for chemical combination is a useful antidote. But whether the less severe disturbances from smaller doses occur by withdrawal of calcium is still not certain. A product which develops physiologically in the protein splitting of supportive substance may also have immediate actions on the metabolism of this supportive tissue.


The provings of oxalic acid are found:

1. Reil: Hom. Vierteljahrsschr., Bd. 2, p. 305, 1851.

2. Hering: Ameriken Arzneiprufungen, S. 525, 1857 (here also the earlier ones).


The local irritative manifestations on the gastrointestinal canal and urinary passages give fewer therapeutic indications than the symptoms reported from the nervous system.

Here first are the neuralgias. They appear paroxysmally in circumscribed small places or as cutting pains throught the arms and from the back over the thigh. Many paraesthesias, crawling, numbness, prickling, coldness occurs in the back or in the extremities, like-wise itching. On the skin are patches of marbled livid appearance. Hands and feet are cold as if dead; coldness runs along the back. There is also a great feeling of weakness as if the back was too weak to support the body. The feeling of crushing in the testicular and spermatic cord neuralgias is particularly stressed. Oxalic acid is also to be considered for organic diseases of the cord and a modality which holds not only for the neuralgias but also for the cardiac and urinary symptoms obtains here: the psychic influence predominates over all irritative symptoms; all complaints are aggravated by thinking about them; attentiveness to complaints. Moreover in general movement aggravates. The pains are often considered as rheumatic and the connection of oxalic acid to protein metabolism of the supportive substance permits this possibility to remain open.

The severe cardiac symptoms of poisoning have their predecessor in severe palpitation which is worse at night on lying down. When thinking about the heart, the pulse intermits. A connection with rheumatism is thereby not particularly probable. Sudden stitch in the cardiac region interrupting breathing, in view of the other characteristics of the remedy, need give no occasion for including organic diseases of the heart, pleura or lungs in its field of action.

In the stomach burning pains and sensitiveness to contact, in the abdomen pains and burning in small areas are noted. The diarrhoea is said to be produced by coffee; neither the diarrhoea with colic about the umbilicus nor the tormenting vomiting of poisoning gives any special point of departure for the selection of acidum oxalicum. The headaches are said to be worse before and during the stool (afterwards better?). The use of wine aggravates the headaches. Strawberries are apparently not tolerated.

The irritative manifestations in the urinary passages have led to therapeutic use when the urgency and pressure of urination is renewed by thinking about it.


Chief Trend:

Neuralgia, paroxysmally at circumscribed places. Paraesthesias. Cutting pains. Weakness of back. Spermatic cord neuralgia.


All complaints worse thinking about them. Worse from movement. Palpitation on lying down.

(Diarrhoea worse from coffee. Headache worse from the use of wine, worse before and during stool.)

DOSE —- This rarely used remedy is recommended usually in the D 6 but also in D 12 and D 30.

Cerium oxalicum, the oxalate of the only rare earth which has been therapeutically used to the present, is not proven but in the lower triturations has been recommended in hyperemesis gravidarum and other forms of reflex vomiting and cough. The action does not seem to be very useful.


Citric acid, CH2.COOH-C(OH)COOH-CH2.COOH, produces experimentally very similar intoxications to those of oxalic acid and which are also traced back to calcium precipitation; however in man the poisoning from internal administration is very rare. The corrosive action is not particularly great.

The action of the juice of citrus fruits in scurvy cannot be ascribed to the citric acid but only the vitamine content. But on the other side a case of scurvy has been reported from the excessive use of citrons for the prevention of yellow fever. 582 The tendency to bleeding is increased by the excessive use of ju- ice of citrus fruits. The reduction or prevention of coagulation of the blood by sodium citrate is generally known. In those who are sensitive, citric acid can produce vomiting and headache.

Citric acid itself is not proven. So only the external use of citrus juices for the pain of carcinoma of the tongue and the internal lay use in chronic rheumatism, dropsy and menstruation need be mentioned.


Tartaric acid, CH(OH).COOH-CH(OH).COOH which appears in many fruits, especially in grapes, produces inflammation and irritation of the digestive passages with burning as if from fire and drawing pain in the soles of the feet particularly near the heel after the ingestion in large amounts. 583 Outside of the neutralization in poisoning with alkalies, tartaric acid is not used therapeutically. Also in homoeopathy, neither it nor the potassium salt, cream of tartar, has obtained significance.

Otto Leeser
Otto Leeser 1888 – 1964 MD, PHd was a German Jewish homeopath who had to leave Germany due to Nazi persecution during World War II, and he escaped to England via Holland.
Leeser, a Consultant Physician at the Stuttgart Homeopathic Hospital and a member of the German Central Society of Homeopathic Physicians, fled Germany in 1933 after being expelled by the German Medical Association. In England Otto Leeser joined the staff of the Royal London Homeopathic Hospital. He returned to Germany in the 1950s to run the Robert Bosch Homeopathic Hospital in Stuttgart, but died shortly after.
Otto Leeser wrote Textbook of Homeopathic Materia Medica, Leesers Lehrbuch der Homöopathie, Actionsand Medicinal use of Snake Venoms, Solanaceae, The Contribution of Homeopathy to the Development of Medicine, Homeopathy and chemotherapy, and many articles submitted to The British Homeopathic Journal,