Most ants spray or inject a venom, the main constituent of which is formic acid only in the case of subfamily Formicinae.

Of all extant ant species, about 71% are considered to be stinging species, as some subfamilies have evolutionarily lost the ability to sting.

In the case of fire ants, the venom consists mainly of alkaloid (>95%) and protein (<1%) components.

[3]: 450 First aid for fire ant bites includes external treatments and oral medicines.

[citation needed] Severe allergic reactions can be caused by ant stings in particular and venomous stings in general, including severe chest pain, nausea, severe sweating, loss of breath, serious swelling, fever, dizziness, and slurred speech;[5] they can be fatal if not treated.