Oxalic Acid. (C2H2O4 plus 2H2O). Trituration and tinctures. Poisoning by oxalic acid (” salts of lemon, ” “salts of sorrel”) is not uncommon owing to its accessibility and its resemblance to Epsom salts.
The gross gastro-intestinal symptoms are due to its physico- chemical action on the digestive tract and need not be dwelt upon. The effects upon tissues or organs remote from that tract and those induced when the drug is introduced otherwise than by the mouth and those obtained by provings are definite and important.
Nervous system.-Considerable doses soon induce rapid and deep breathing, increase of arterial tension, and twitching of muscles, especially of the face. Later, great muscular weakness is induced with slow and difficult respiration, or irregular spasmodic breathing, weak fluttering pulse, pallor or cyanosis. When the dose is large enough the spasm of the chest muscles arrests the breathing, and coma or convulsions end in death. In some cases acute or agonizing pains in the loins extending down the thighs occur, associated with numbness, formication, anaesthesia of finger-tips, weakness of back and legs making walking difficult; or restlessness, necessitating constant change of position, may be present.
In dogs, stiffness of the hind legs, followed by jerking backwards of the head, or extension of legs, tail and head, going on to opisthotonos, are produced. The spasms subsequently give place to paralysis, but they may be excited for a time by striking the parts. Complete relaxation with coma precedes death.
With very large doses convulsions come on at once and mask most of the other symptoms.
Ingested oxalates are excreted by the kidney, and renal symptoms are due to the mechanical irritation of the crystals, or to blocking of the pyramids by them; oxaluria results.
The drug undoubtedly causes lessening of lime in the bones, and Cushny states most of the conditions produced are due to precipitation of lime salts in the tissues.
The lungs seem to be affected, apart from the disturbance of respiration alluded to, in the shape of shooting pains in the region of the left base, and dry cough. Post mortem, superficial redness and engorgement of that part of the lung were found. Though this does not seem to be a constant effect it is worthy of record.
Small and repeated doses cause dull pains in the vertex and forehead; palpitation of the heart worse at night on first lying down, irregular cardiac beat, loss of voice, salivation, dilated pupils and diuresis. Exhilaration and quickened thought may be early results of the drug, and thinking about the pains causes aggravation or return of them (bary. carb., helonias).
Nervous System.-Anomalous nerve pains of shooting character in the back and limbs have been cured by oxalic acid, and the spastic symptoms of chronic spinal diseases mitigated. Distressing constriction of chest in the same diseases has like- wise been helped, and the lightning pains of tabes dorsalis.
In some influenzal pains of the back, where a spasmodic element develops, oxalic acid is useful. The drug should also be considered in spinal meningitis, in the early stages of encephalitis lethargica, and in rheumatic pains coming on suddenly in small areas, associated with very acid urine. Spinal neuralgia, extending into arms and legs especially if associated with weakness, numbness and coldness of the latter, indicated oxalic acid.
It has also been used with success for sexual excitement with amorous dreams, for involuntary emissions in spinal cases and for testicular neuralgia.
The somewhat slight evidence of pulmonary lesions has been utilized clinically with success in inflammation of the base of the left lung, with sharp (pleuritic?) pains. then is fully conscious. Memory fails, there is apathy, indifference or a settled despair. Mental symptoms develop before the physical and are more pronounced (ac. mur the reverse). Illusions of the senses may be presents, bells are heard or sparks seen. A peculiar illusion is that the feet are going up in the air towards the ceiling (Passif). The hair turns grey and a very haggard, hopeless look obtains.
Pains, as of a weight on the vertex, or pain in the nape and occiput occurs. The legs tremble in walking, the patient is tried and exhausted and wants to lie down. Standing and sitting up weary him, he is less tired walking about. There is increased sensitiveness to light, noise (especially music), and to odours (especially coffee). Dimness of sight and roaring in the ears, with difficult hearing, are other expressions of his nervous debility. A sensation of pressure, as of a crushing weight is common and is felt principally in the vertex, forehead, eyes and sternum.
Periosteal pains, “as if the bones were scraped,” are caused by phosphoric acid, and in one prover a constant long-lasting pain about the left shoulder and the left radial nerve was produced. These pains were worse at night and from lying on the affected side and better for movement, by which the circulation in the part is improved. This latter modality is characteristic of the pains of phosphoric acid. Drawing pains in the fleet and big toes are also induced.
The skin perspires freely, especially towards morning, and the hair falls out (nat. mur., selen.). There may be formication over the whole body, more especially of parts covered with hair.
Digestive Systems.- Phosphoric acid causes aversion from coffee and a sensation of pressure or lump in the stomach. It produces meteoristic distention of the abdomen, with gurgling and tenderness, accompanied with very profuse and persistent diarrhoea which is watery, white and painless, a peculiarity of which is that it does not exhaust the patient, and, indeed, often relieves other symptoms. Frequent discharge of flatus smelling of garlic occurred in one prover. The sphincters are weakened, and on coughing involuntary escape of stool (* Phosphorus) and of urine (* Causticum, *Nat., Murex, *Pulsatilla, *Sepia) takes place. Phosphoric acid has no known action on the kidneys, but the composition of the urine is changed, it contains an excess of phosphates in solution, or deposits them, causing the urine to have a milky appearance. The quantity of urine to have a milky appearance. The quantity of urine is largely increased.
Sexual Organs.- The debility produced by phosphoric acid is particularly manifest in the sexual organs, both male and female; in the former entailing frequent weak emissions, dragging, aching in the testes, and impotence;and in the later, excessive and premature menses, which are often accompanied by pain in the hepatic region. Sensation in the uterus as if filled with wind, meaning perhaps, hypogastric distension.
In one of the provers phosphoric acid apparently produced a capillary bronchitis with dyspnoea, aching pain under the sternum and copious expectoration, and in another a cough with hawking of thin salt mucus. The haemorrhages of phosphoric acid are dark, profuse and passive, e.g., epistaxis of dark blood.
Phosphoric acid is used in states of debility similar to those it produces. It has, therefore, found its place in ailments caused by continual grief, over-exertion of mind or body, sexual excesses or other drain on the system, such as prolonged lactation and menstrual losses (*China) It is used for the effects of disappointed love (*Ignatia, *Nat., *Mur.) and for home- sickness (*Capsic.)
A common ailment from these causes is headache, as fro example, the headache of over-worked schoolgirls. The headache is mostly a heavy pressure on the vertex, is better from lying down (*bry., *Gelsemium, *Silicea) and from sleep, even though only of short duration.
The profuse diarrhoea of phosphoric acid, together with the mental apathy, drowsiness and prostrations, renders it a valuable remedy in certain stages of typhus and enteric fever, and in low fevers where the nervous system rather than the blood is affected by the poison. It is also useful in summer diarrhoea. In these diarrhoeas the distinguishing features calling for phosphoric acid are that the stools are copious, white or yellow, painless and often involuntary and do not exhaust the patient.
The polyuria suggests that it should be useful in diabetes insipidus, and this has been found to be the case, but it has also been of advantage in diabetes mellitus when the complaint has had a nervous origin, as when business worries or the shock of the death of relatives has apparently originated the disease.
In the sexual sphere it is indicated in weakness of the organs, especially in spermatorrhoea and impotence brought on by sexual excesses or masturbation and for the general evils caused by masturbation in either sex, notably when the patient is distressed by the culpability of his act. In the female sex it is useful for excessive and premature menses when accompanied by great debility and pain in the hepatic region. It also serves in debility resulting from lactation or leucorrhoea, which is this and acrid.
In the chest complaints for which the drug is suitable the cough is excited by tickling low down in the chest in the neighborhood of the epigastrium, it is worse in the evening and from lying down. The cough causes headache (*Belladonna, *Nat., *Mur., *Phosphorus, *Sulph.), nausea and vomiting of food and spurting of urine (*Causticum, *Nat. *Mur., *Pulsatilla, *Sepia). The sputum is copious, muco-purulent, salty, bloody, and offensive. Every draught of air causes a fresh cold. The chest feels weak from talking (*Stann.) and coughing, but relief is obtained from walking. In phthisis with profuse diarrhoea and perspirations phosphoric acid is indicated.
(1) Mental and nervous debility; mild, yielding temperament.
(2) In their states of apathy and drowsiness patient can easily be roused to full consciousness, but soon relapse.
(3) Diarrhoea which is profuse, painless and does not debilitate, and may bring relief.
(4) Weakness in the chest from coughing.
(5) Sensations of pressure or weight.
(6) Passive haemorrhages from mucous surfaces.
(7) Sexual weakness, the result of excesses or masturbation.
(8) The headache are worse from noise, especially music, and from movement. Headaches of schoolgirls from overwork.
(9) Persons of originally strong constitution weakened by loss of fluids, excesses, violent or acute diseases, chagrin, or a long succession of depressing emotions.
(10) Children and young people who have grown too rapidly, tall, slender and thin. If weakness be considerable, emaciation take place, the face is pale and the eyes sunken and surrounded with bluish areas.
By noise (especially music), odours which cause vomiting, bad news, being talked to, movement (headache), depressing mental conditions, loss of fluids (especially semen), touch, sitting and standing, cold, draughts, wind, snow-air, lying down (cough), movement (pains).
By sleep, even a short sleep, walking, fresh air, keeping warm (diarrhoea).