Kalium arsenicosum
Potassium arsenite · Potassium arsenate, Fowler’s solution. · Mineral
Kali. ars. is most suitable for people who are very anxious, especially about their health, and is similar in profile to Arsen. alb. (see page 68). Those affected may experience great mental and physical restlessness, with nervousness, depression, anemia, and hypersensitivity to touch and noise. They have a tendency to be either quarrelsome and excitable, or withdrawn, timid, and indifferent.
Key physical symptoms associated with this remedy are chronic or malignant skin problems. The skin typically burns and itches, becoming worse on undressing and for the cold; cracks may develop in the bends of the knees and arms. This is usually symptomatic of eczema, psoriasis, acne, or ulcers. The remedy may be used to ease skin cancer, and for varicose veins on the legs that have become ulcerous.
In addition, the remedy may be given for asthma with rapid, anxious breathing, which may become worse after midnight.
Key symptoms
- Intolerable itching worse when undressing
- Chronic eczema; itching worse from warmth, walking, and undressing
- Psoriasis and lichen; dry, scaly, wilted skin
- Skin cancer with sudden alarming malignancy
- Numerous small nodules under the skin
- Phagedaenic ulcers; fissures in bends of arms and knees
- Acne; pustules worse during menses
- Gouty nodosities worse on change of weather
- Cauliflower excrescences of os uteri with foul discharge
- Restless, nervous, and anaemic constitution
Worse (aggravation)
Better (amelioration)

Fowler's Solution (KALI ARSENICUM)
The Kali ars patient tends towards malignancy, and inveterate skin diseases. He is restless, nervous and anæmic.
Skin
Intolerable itching, worse undressing. Dry, scaly, wilted. Acne; pustules worse during menses. Chronic eczema; itching worse from warmth, walking, undressing. Psoriasis, lichen. Phagedænic ulcers. Fissures in bends of arms and knees. Gouty nodosities; worse, change of weather. Skin cancer, where suddenly an alarming malignancy without any external signs sets in. Numerous small nodules under skin.
Female
Cauliflower excrescences of os uteri, with flying pains, foul smelling discharge, and pressure below pubis.
Relationship
Radium.
Dose
Third to thirtieth potency.

Kali arseniatum. Potassium arsenite. KH2 ASO3. "Fowler's Solution," the form in which Kali ars. has been tested, consists of Arsenious acid 1 part, Carbonate of potash 1 part. Compound tincture of lavender 3 parts, distilled water 95 parts. Dilutions should be made from this.
Clinical
Bright's disease. Cancer. Deafness. Diarrhœa. Dropsy. Eczema. Epithelioma. Exophthalmos. Eyes, affections of. Herpes zoster. Jealousy. Measles. Melancholy. Miliary rash. Neuralgia. Neurasthenia. Psoriasis. Skin, affections of. Tongue, neuralgia of. Varicose veins. Ulcers.
Characteristics
It is not possible to separate entirely the pathogenesis of Ars. alb. and Kali ars. Kali ars. is the favourite form in which Arsenic is prescribed by the allopaths, consequently the bulk of observations from over-dosing are due to this preparation; and as it is named Liquor arsenicalis it is considered as Arsenic and nothing else. However, a sufficient number of pure observations have been made to warrant a separate consideration. The …

Phatak's chapter on Kalium arsenicosum is available in the app.
Read Phatak in the appClassical texts are in the public domain. Educational reference only — not medical advice.