Educational information, not medical advice — ask your doctor or midwife.
Ferrum arsenicosum is a homeopathic remedy. Its source is iron arsenate, a salt of iron and arsenic. The Latin name is Ferri arsenias, and it is also called iron arsenate.
Homeopaths pick it for people who look pale and tired. They also use it for puffy skin under the eyes and for itchy skin. None of these uses has been tested in a proper trial.
The remedy is made by diluting the source over and over again. At 30C, none of the starting material is left in the pellet. Tests cannot tell such a remedy apart from a dummy pill.
Long use in a tradition is not proof that a thing works. This page tells you both: what the tradition says, and what the tests show.
One point matters more here than with most remedies. Arsenic is a poison and a known cause of cancer. Low dilutions, such as 3X or 6X, can still hold small amounts of it.
There is no known way for this remedy to act on the body once it is well diluted.
Homeopathy rests on two old ideas. The first is "like cures like": a substance that causes signs in a well person is said to ease the same signs in a sick one. The second is that shaking each dilution makes the remedy stronger.
Neither idea fits what we know about chemistry. A 30C dilution is roughly one part in a number with sixty zeros. No atom of the source is likely to remain.
Any benefit people report is best explained by placebo, by time, or by the care and attention of a long consultation. Those things are real, but they are not the remedy acting on your body.
The most common form is a small sugar pellet that you let melt under your tongue.
You can also find liquid drops. These are held in alcohol or in water. Some brands sell a tablet you dissolve in the mouth.
Strengths are written as numbers with a letter. Common ones are 6X, 6C, 30C and 200C. The higher the number, the more the source has been diluted.
A 30C pellet holds no source material. A 3X or 6X product may still hold arsenic, so treat those as a real risk rather than a gentler option.
Ferrum arsenicosum came into homeopathy in the 1800s. Homeopaths tested it on healthy people and wrote down what they felt. That list of signs became the guide for prescribing it.
It has never been a leading remedy. It sits in the older reference books as a minor one, used for pale, tired, puffy patients. Its record is one tradition, not many.
Some reactions to Ferrum arsenicosum need urgent care. Call your local emergency number or go to an emergency department straight away — do not wait to see whether it passes.
See a doctor if you feel tired and look pale for more than a couple of weeks. Blood tests can find the cause.
Get checked soon if your face, eyelids, hands or ankles swell, or if you pass much less urine than usual.
Get urgent help if you have stomach pain with vomiting and watery stools after taking a low-strength product. Numb or tingling hands and feet, or an uneven heartbeat, also need help straight away. Take the pack with you so staff can see the strength.
Call your local poison centre or emergency number if a child swallows a low-strength product.
Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.
What it is typically used for, usual dose, cautions, and the study behind it where real trial data exists.
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