Formic acid is a nature-identical and biodegradable organic acid that is also antiseptic and has a strong tart smell. The formic acid in itself is corrosive and should be handled with caution, but in wart treatment it has a dehydrating effect. Formic acid can, for example, be found when upsetting an anthill. The ants emit this acid as a part of their defence system. If you have a wound on your hand and stir around in the anthill, you will get a strong burning feeling in the wound. Formic acid can also be found in very high concentration in a stinging nettle.
There are many different uses for formic acid; among other things the substance is used in the production of insulin in the pharmaceutical industry. It is also used in different softening and anti-itching body oils as well as in cures for rheumatism for relieving inflammation, pain and joint pain. Formic acid is also used in ensiling of silage crops for preservation during winter. Crops as food for animals can thereby be saved for the winter. Lactic acid bacteria acidify the crops, thereby conserving it.
1 Patient leaflet
2 Bhat et al., International Journal of Dermatology 2001, 40, 415±419.