What is Lachesis mutus?

Lachesis mutus is a homeopathic remedy. It is made from the venom of the bushmaster snake, a large pit viper of South America. The snake is also called surukuku.

Homeopaths give it for hot flushes, night sweats and sore throats. It is also used for symptoms that start on the left side of the body. It is a single remedy, so it is taken on its own.

The venom is diluted over and over, so at 30C not one molecule of it is left. Trials do not show that it beats a dummy pill. Lachesis has a long place in homeopathy, but long use is not proof of effect, and this point is made once here only.

How does Lachesis mutus work?

Homeopathy is built on the idea that "like cures like". Raw bushmaster venom causes bleeding, heat and swelling. So homeopaths give the diluted venom to people with flushing, throbbing or bleeding problems.

Each step of the making adds water or alcohol and a hard shake. Homeopaths believe this leaves an imprint of the venom behind. There is no known way in physics or biology for that to happen.

By 12C, and far more so by 30C, no venom is left at all. So the remedy has no known way to act on your body. Any change you feel is most likely a placebo effect (feeling better because you expect to).

What forms does Lachesis mutus come in?

The most common form is a small sugar pellet that you let melt under the tongue. Liquid drops in an alcohol base are also sold.

Usual strengths are 6C, 12C, 30C and 200C. Some homeopaths also use LM strengths. The bigger the number, the more the venom has been diluted away.

Pellets are usually made with lactose (milk sugar). Drops usually contain alcohol. Check the label if either matters for you.

Where it comes from:

Lachesis came into homeopathy in 1828. Constantine Hering, a German-born doctor working in South America, prepared the venom and is said to have tested it on himself.

It soon became one of the best known remedies in homeopathic practice. It is still listed in homeopathic texts and sold worldwide today. Its standing is within homeopathy alone, not in older herbal or folk systems.

What does Lachesis mutus help with?

• Hot flushes and night sweats around menopause: This is the best known use in homeopathy. Homeopaths pick it for flushes that rise upward, with a red face and a dislike of anything tight on the neck. We could not find a trial of Lachesis on its own for flushes. A few studies tested mixed homeopathic products that contained it, which cannot tell you what one ingredient did.
• Sore throat, mainly on the left side: Homeopaths use it for a throat that hurts more on the left, and more when swallowing liquids or saliva. There is no trial evidence for this use. A sore throat with fever, drooling, or trouble breathing or swallowing needs a doctor the same day. Do not treat that at home.
• Premenstrual tension and mood swings: Traditional homeopathic texts describe a picture of talkativeness, jealousy and tension that lifts once bleeding starts. That is a prescribing picture, not a tested effect. No human trial supports Lachesis for premenstrual symptoms.
• Varicose veins and heavy legs: Because raw venom affects blood and vessels, homeopaths link the remedy to purple, congested veins. Again, this reasoning is traditional. No trial shows the diluted remedy changes veins, swelling or leg pain. Compression stockings and medical review have real evidence behind them.
• Throbbing headaches: It is chosen for left-sided, pounding headaches that feel worse after sleep and better in fresh air. No trial evidence supports this. A sudden, very severe headache, or one with weakness, confusion or a stiff neck, is an emergency.

Which foods are rich in Lachesis mutus?

This is a prepared remedy, not a nutrient, so no food contains it.

What are the side effects of Lachesis mutus?

• No direct effects are expected at 12C and above, because no venom remains
• Stomach upset or wind in people who cannot digest lactose (milk sugar) in the pellets
• A rare rash or allergy to something in the pellet or the liquid base
• Alcohol in liquid drops, which matters for children and for people avoiding alcohol
• A short flare of symptoms that homeopaths call an aggravation, which has not been shown to be real
• The main real risk: putting off treatment that works while you try the remedy

Good to know:

Direct harm from a 30C remedy is very unlikely, because it is mostly sugar or diluted alcohol.

The serious risk is what you do not do. Delaying care for a bad infection, heavy bleeding or heart symptoms can cause real harm.

Poorly labelled products are a separate worry. Anything holding actual venom could affect clotting and cause bleeding.

How much Lachesis mutus should you take?

• Recommended daily: No proven dose exists, because the remedy has not been shown to do anything a dummy pill does not do. In practice, homeopaths most often use 30C. A common self-care pattern is 3 to 5 pellets, or 5 drops, once or twice a day. Higher strengths such as 200C are usually given as a single dose by a practitioner. Never take a product that lists real snake venom instead of a homeopathic dilution.
• Best time of day: Any time of day. Homeopaths often advise taking it away from strong tastes and smells, such as coffee, mint toothpaste or camphor rubs. That advice is tradition, not a tested rule.
• With or without food: Usually taken on an empty mouth, about 15 minutes before or after food or drink. This is custom in homeopathy, not a proven need.
• Time to effect: Homeopaths expect a change within hours to a few days. There is no reliable evidence of any effect at all beyond placebo, so treat any promise of a set timeline with care.
• How long to take it: Homeopaths usually suggest a few days for a short-term complaint, then stopping. If nothing has changed in about a week, stop and think again. Do not keep taking it for months in place of care that works. For an ongoing problem such as menopause symptoms, see your doctor rather than self-treating for long periods.