Educational information, not medical advice — ask your doctor or midwife.
Crotalus horridus is a homeopathic remedy. It is made from the venom of the timber rattlesnake. Homeopaths pick it for people who bleed or bruise easily, or who feel weak and very unwell.
The venom is watered down again and again in water and alcohol. Each step is shaken hard. At 30C, the strength most often sold, none of the venom is left in the drops or pellets you take.
Here is the plain verdict. Trials do not show that homeopathic remedies do more than a placebo, which is a dummy pill with no drug in it. This remedy has a long place in homeopathy, but long use is not proof that something works.
Short answer: there is no known way for it to work in the body. At 30C no venom is left, so there is nothing there to act on your cells.
Homeopathy rests on two old ideas. The first is that a substance which causes symptoms in a well person can treat like symptoms in a sick person. The second is that shaking each dilution leaves some trace of the starting substance behind.
Chemistry does not back the second idea. When people feel better, the likely reasons are time, rest, care and attention, or placebo (feeling better because you expect to).
Most often you will see small sugar pellets that melt under your tongue.
Other forms are liquid drops in water and alcohol, soft tablets, and granules. Labels show 6C, 30C, 200C or 1M on one scale, or 6X and 12X on another.
A higher number means more dilution steps. Past 12C, no venom at all remains in the product.
The remedy comes from the United States in the 1830s. Constantine Hering, a homeopath, tested rattlesnake venom on himself and others in 1837 and wrote down the symptoms they reported.
It went on to become one of the best known snake remedies in homeopathy. Homeopaths of the yellow fever years reached for it when a person bled and collapsed.
It is still listed today in homeopathic materia medica, the reference books that describe each remedy.
Get emergency help now if you are bleeding and it will not stop, if you vomit blood, if your stools are black or bloody, or if you feel faint, cold and clammy.
See a doctor the same day for yellow skin or eyes, a fever with shivering and confusion, a new rash with blisters and burning pain, or one leg that is hot, red and swollen.
Book a normal appointment if you bruise easily for no clear reason, your gums bleed often, your periods are much heavier than usual, or you still feel drained weeks after an illness.
Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.
Reviewed by the HealisticMD editorial team How we grade evidence →
The published evidence for Crotalus horridus is weak or absent. That usually means no controlled trial has tested it, not that a trial found it ineffective — the two are different, and we grade only what has been published.
What it is typically used for, usual dose, cautions, and the study behind it where real trial data exists.
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