Apitoxin, or honey bee venom, is a bitter colorless liquid containing proteins, which may produce local inflammation. It may have similarities to sea nettle toxin.

Apitoxins are under preliminary research for their potential biological effects, such as in cancer.

A bee sting is a sting from a bee (honey bee, bumblebee, sweat bee, etc.). The stings of most of these species can be quite painful, and are therefore keenly avoided by many people.

Bee stings differ from insect bites, and the venom or toxin of stinging insects is quite different. Therefore, the body's reaction to a bee sting may differ significantly from one species to another. In particular, bee stings are acidic, whereas wasp stings are alkali, so the body's reaction to a bee sting may be very different than to that of a wasp sting.

The most aggressive stinging insects are vespid wasps (including bald-faced hornets and other yellow jackets) and hornets (especially the Asian giant hornet). All of these insects aggressively defend their nests.

Although for most people a bee sting is painful but otherwise relatively harmless, in people with insect sting allergy, stings may trigger a dangerous anaphylactic reaction that is potentially deadly. Additionally, honey bee stings release pheromones that prompt other nearby bees to attack.

The first step in treatment following a bee sting is removal of the stinger itself. The stinger should be removed as quickly as possible without regard to method: studies have shown the amount of venom delivered does not differ whether the sting is pinched or scraped off and even a delay of a few seconds leads to more venom being injected. Once the stinger is removed, pain and swelling should be reduced with a cold compress. A topical anesthetic containing benzocaine will kill pain quickly and menthol is an effective anti-itch treatment. Itching can also be relieved by antihistamine or by a steroid cream.

Many traditional remedies have been suggested for bee stings including damp pastes of tobacco, salt, baking soda, papain, toothpaste, clay, garlic, urine, onions, aspirin or even application of copper coins. As with jellyfish stings, ammonia and ammonia-containing liquids, such as window cleaner, are often suggested as a way to immediately cleanse the skin and remove excess venom, and sweat itself (which also contains small amounts of ammonia) may provide some small relief.

Bee venom is acidic, and these interventions are often recommended to neutralize the venom; however, neutralizing a sting is unlikely to be effective as the venom is injected under the skin and deep into the tissues, where a topically applied alkali is unable to reach, so neutralization is unlikely to occur. In any case, the amount of venom injected is typically very small (between 5 and 50 micrograms of fluid) and placing large amounts of alkali near the sting site is unlikely to produce a perfectly neutral pH to stop the pain. Many people do claim benefit from these home remedies but it is doubtful they have any real physical effect on how much a sting hurts or continues hurting. The effect is probably related to rubbing the area or the mind perceiving benefit. Furthermore, none of these interventions have been proven to be effective in scientific studies and a randomized trial of aspirin paste and topical ice packs showed that aspirin was not effective in reducing the duration of swelling or pain in bee and wasp stings, and significantly increased the duration of redness. The study concluded that ice alone is better treatment for bee and wasp stings than aspirin.

The sting may be painful for a few hours. Swelling and itching may persist for a week. The area should not be scratched as it will only increase the itching and swelling. If swelling persists for over a week or covers an area greater than , medical attention should be sought. Doctors often recommend a tetanus immunization. For about 2 percent of people, a hypersensitivity can develop after being stung, creating a more severe reaction when stung again later. This sensitisation may happen after a single sting, or after a series of stings where they reacted normally. A highly allergic person may suffer anaphylactic shock from certain proteins in the venom, which can be life-threatening and requires emergency treatment. People known to be highly allergic may carry around epinephrine (adrenaline) in the form of a self-injectable EpiPen for the treatment of an anaphylactic shock.

For patients who experience severe or life-threatening reactions to insect stings, allergy injections composed of increasing concentrations of naturally occurring venom may provide protections against future insect stings.