Psora is one of the three chronic miasms responsible for diseases of humanity. The others being Syphilis and Sycosis. Psora is most primitive one, from which perhaps no living organisms on earth remains unaffected. Its history dates back even to times of ancient Greek and Egypt, which in the form of plagues and leprosy cast a shadow of death. However during olden days it was not complex as it is today. Due to the change in the life style, over indulgence in bad habits and evil thinking it has been greatly evolved into a complex entity. The vast majority of diseases suffered by humanity are as a result of the influence of this miasm. Hence it is called as the mother of all diseases.

Dr. Samuel Hahnemann coined the word "Psora". It is derived from Greek, which means itch. It also has its origin from Hebrew word "Tsorat", meaning "a groove, a fault" which refers to a deficiency state of human being. This deficiency state destabilizes the equilibrium of health giving rise to diseases.

After the discovering the law of cure, Hahnemann experienced many difficulties during his practice with homoeopathic medicines. The acute diseases used to yield to these medicines, but the same conditions would reappear again and again. No matter how hard he tried, he could not completely extinguish such tendencies from the patients. This made Hahnemann to think that some hidden thing was present in the dynamic aspect of every patient, which made patients susceptible to external influences thereby leading to these repeated acute attacks. After interpreting his observations and careful study of past medical records, he came to the conclusion that some inherent latent and dynamic cause existed within organism, and was main culprit behind the outbreak of chronic and acute disease. He named this unknown destructive force as PSORA.

Psora makes itself known primarily on the skin in the form of itch or eruption. All the skin manifestations, swelling of glands, sarcomatous and carcinomatous tumours, deformed bony structures, haemorrhagic tendencies, all suppurations, functional disturbances, nutritional disturbances, all of acute manifestations manifest due to psora. Every part and function of the body is influenced by this miasm. Psoric conditions always itch. There is considerable itching of skin. All the subjective symptom manifestations are due to underlying psora.

• SENSORIUM: Vertigo from walking, looking up, digestive disturbances and rising. Vertigo aggravated from emotional disturbances, relieved by lying down.

• HEAD: Sharp, paroxysmal headaches in morning, increasing as the sun rises and relieved as sun sets. Throbbing headaches better by rest, sleep and hot applications. Lustreless and dry hair. Falling of hair. Premature greying of hair. Hair break and ends split. Scalp dry. Itching, dandruff and dry eruptions on scalp worse open air, evening, better by scratching.

• EYES: Functional disturbances. Cannot tolerate sunlight. Spots before the eyes. Symptoms worse in the morning and better by heat.

• EARS: Functional symptoms. Dry ear canal. Oversensitiveness to sound.

• FACE: Dry unwashed appearing face. Face red hot and shining during fever. Dry itching pimples. Hot flushes. Rush of blood to face.

• NOSE: Oversensitive to odors. Painful boils and pimples on nose.

• MOUTH: Sordes about mouth. Swelling and burning of lips. Lips dry and parched. Stomatitis and thrush. Perversions of taste. Burnt taste.

• STOMACH: Great hunger. Hunger even after full stomach. Craving for sweets, acids and sour things. Craving for indigestible things during fever. Weak gone feeling in the stomach. Lack of assimilation. Fullness, gas and bloating accompanying heartburn and waterbrash. Aggravation after eating. Desires hot foods.

• CHEST: Dry teasing spasmodic cough. Scanty tasteless expectorant. Violent rush of blood to chest. Sensation of weakness, goneness or fullness about the heart. Sensation as of a band around chest. Fear of death from heart trouble. Heart troubles brought about by strong emotions.

• ABDOMEN: Fullness and distension of abdomen after eating. All pains relieved by heat.

• RECTUM: Diarrhoea from overeating. Morning diarrhoea. Spasmodic offensive and painless diarrhoea which relieves suffering. Diarrhoea from taking cold, worse by cold, relieved by hot drinks or heat in general. Persistent constipation with small hard difficult stools with no desire for stool.

• URINARY: Retention of urine in children and old age after getting cold. Smarting and burning on urination. Involuntary urination.

• GENITALIA: Menstrual complaints from emotional disturbances. Dysmenorrhoea, amenorrhoea.

• SKIN: Skin dry rough, dirty and unhealthy with itching, dry and scaly eruptions.

• EXTREMITIES: Psoric individuals cannot stand for long time. He must lean on some support to lessen his body weight on his feet. This is because of his natural desire to rest.

Psora also exhibits its peculiar property of becoming latent without any manifestations unless excited by some sudden exciting factors. Psora can remain in latent state for long time, even for years, displaying characteristics of its latent property, only to be observed by physician conversant with these characteristics. This latent state may be brought out to full power by some exciting cause like accidents, exposure to extremes of climate, infections, indisposition, shock etc. Some of the prominent latent characters of the psora are as follows.

• Psoric patients are alert, quick and active both in mental and physical aspect. But they are easily fatigued by mental or physical work.
• Psoric individuals experience flushes of heat during work.
• Psoric patients are very anxious and fearful. We come across all types of anxiety in them.
• They cannot concentrate. Concentration is very difficult.
• They are restless.
• Fits of anger without any desire to harm anyone.
• Sorrow and grief easily influence them. This often leads to outbreak of acute diseases.
• Much depression of spirits.
• All psoric manifestations are better by eliminative functions.