Educational information, not medical advice — ask your doctor or midwife.
Laricifomes officinalis is a shelf-shaped fungus that grows on old larch and other conifer trees.
It is sold as agarikon or quinine conk, usually as a powder, capsule or liquid extract. It is not a food mushroom. The flesh is hard, woody and very bitter.
The name quinine conk comes from that bitter taste. The fungus holds no quinine, and it does not treat malaria.
Here is the honest verdict on evidence. People have used it for more than two thousand years, but long use is not proof that it works or that it is safe. There are no good human trials, so nearly all claims rest on lab and animal work.
The fungus is rare and slow growing, and wild stocks have dropped in Europe and North America. Most careful sellers now grow the mycelium (the root-like body of the fungus) instead of cutting wild brackets.
No one has shown in people what this fungus does in the body. The ideas below come from lab dishes, animals and old doctors' reports.
In test-tube work, water and alcohol extracts slowed the growth of some flu and pox viruses. Other lab tests slowed Mycobacterium tuberculosis, the germ behind TB. Whether any of this happens inside a person is not known.
The fungus holds beta-glucans, a type of sugar chain found in many mushrooms. In cell studies these sugars can switch on immune cells. That is a long way from showing a stronger immune system in real life.
Agaric acid, the main bitter compound, cuts sweating. Nineteenth-century doctors reported this in patients with night sweats, but those reports were not controlled trials.
In lab studies agaric acid also blocks a carrier inside mitochondria (the parts of the cell that make energy). This helps explain why large amounts irritate the gut and are not harmless.
You will most often meet it as a capsule or a loose powder. Both are usually made from grown mycelium rather than wild wood-grown brackets.
Common forms:
- Capsules or tablets of dried powder. - Dual extracts, made with both hot water and alcohol. - Tinctures sold with a dropper.
- Dried chunks or slices for long simmering. - Blends that mix it with reishi, turkey tail or chaga.
Mislabelling is a real problem in this market. Tests of mushroom products often find the wrong species, or grain filler instead of fungus. Choose sellers who name the species in Latin and show third-party testing.
Greek and Roman writers prized this fungus. Dioscorides described agarikon in the first century CE, and later writers called it a long-life remedy.
Old European use covered coughs, wasting illness, poisons and sluggish bowels. By the 1800s, pharmacies sold agaricin, a refined extract, to dry up the night sweats of tuberculosis. That use faded once modern TB drugs arrived.
Peoples of the Pacific Northwest coast knew the bracket well. It held a strong spiritual role, was carved into figures, and was placed with the dead; some groups also used it in healing.
These records tell you the fungus was valued. They do not tell you it worked, and none of them should be copied at home.
Stop taking it and see a doctor if you get:
- Vomiting or diarrhoea that does not settle within a day. - Signs of dehydration, such as dizziness, dark urine or passing very little urine. - Belly pain that is sharp or keeps coming back. - Yellow skin or yellow eyes. - A rash, swollen lips or face, or trouble breathing. Call emergency services for these.
See a doctor rather than self-treating if you have a cough lasting over three weeks, cough up blood, run a fever, sweat through the night, or lose weight without trying.
In the United States it is sold as a dietary supplement. It is not approved to treat, cure or prevent any disease.
In the UK and EU it is sold as a food supplement, with no authorised medicine status. The species is rare and protected in parts of Europe, so wild picking may be restricted or banned where you live.
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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