Skip to Content

Understanding Bee Stings & Allergic Reactions

Beekeeping comes with one little setback- the stings! Sure, we do our best to avoid getting stung, because once one of the bees stings us, she will die. And, yes, getting stung hurts! But there is a bigger reason to avoid stings, one that could potentially be fatal.

bee sitting on yellow flower

In general, bees are very passive and non aggressive. Many a gardener has tended to their flowers alongside foraging bees. Bees are not inherently dangerous or seek out victims, and only sting when provoked or defending their hive. In fact, “bee stings” are often misidentified wasp stings. Wasps are known for being easily agitated, and because they look similar bees, give bees a bad reputation.

Medical Disclaimer: I am not a physician. The information provided on this website is for informational purposes only and should not be considered to be healthcare advice, medical diagnosis, treatment or prescribing of any kind. Information herein is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician with any questions you may have regarding your medical condition(s).

If you think you are having a medical emergency or condition, call 911 or visit your emergency hospital immediately. Reliance on any information appearing on this website is entirely at your own risk. Full Disclaimer.

Anatomy Of A Sting

Being the only ones equipped with a stinger, only female honey bees can sting. When she stings, she is doing more than just puncturing the skin with her needle-like barbed stinger.

Understanding Bee Stings & Allergic Reactions 1
Honey Bee Stinger Barbs 500x

There are two types of hive sentinels guard bees and defender bees. Guard bees patrol the hive entrances protecting from invaders and inspecting each bee that enters the hive. Defender bees, also known as stingers, respond to out of hive dangers by flying out and stinging or chasing off threats. 9

After a bees stinger breaks through the skin the bee will fly away, ripping her barbed stinger from her body and disemboweling her, later leading to her imminent demise. In a final act of valor, the stingerless bee usually buzzes around the victim’s head to chase it away from the hive.

The stinger shaft has two barbed probes can slide back and forth on the underside of another barbed probe, forming the channel in which venom flows from the venom sac.

Once the stinger and venom sac are removed from the bee as she flies away, a motor apparatus at the base of the stinger begins pulsating. The bee must detach herself from the stinger (by flying or walking away) to activate the pulsation. This pulsing movement causes the barbed probes that make up the stinger to move in opposite directions (reciprocal axial movements to be exact), burying the stinger deeper into the skin. After about 30 seconds, the stinger length will be at least ⅔ embedded. 4

The pulsation that deepens the stinger also serves to pump a venom sac attached to the base of the stinger which injects her venom. Within 20 seconds of the sting, the venom sac releases 90% of its contents, the remaining 10% being delivered within the next 40 seconds. 4


Bee venom is composed of a mixture of proteins, enzymes, polypeptides, amino acids, catecholamines, sugars, and minerals. The trouble from bee venom comes from the mast cell degranulating (MCD) peptide melittin and the enzyme Phospholipase A2(PLA2). 5

Melittin causes the red hot nail-like sharp pain when stung, but also causes tissue damage, mast cell degranulation (which causes vasodilation and anaphylaxis), and an immune response. Phospholipase A2 causes cell damage and death and induces a type 2 immune response (which leads to anaphylaxis). 6

Fun fact- mosquitoes and ticks secrete Phospholipase A2 in their saliva when feeding on blood. 8

If you would like more detailed information on the immune response to bee venom, please see our sources list at the end of this article.


As if getting stung wasn’t enough, the sting also releases alarm pheromones, or chemical messages. Guard bees can also release the alarm pheromone without issuing a sting. Bees excrete these pheromones from the mandibular glands  and stinger sheath glands. Alarm pheromones serve to increase flight activity by other bees, recruit bees from inside the hive and enhance bees responses to moving objects. This is where the smoker comes into play- a gentle puff of smoke interrupts the pheromone communication and limits the number of bees who receive the alarm. 9

Normal Reactions

Most people have some reaction to a bee sting. Bee sting reactions can be classified as mild, moderate or systemic. Mild and moderate stings are considered a normal reaction to the bee venom, and symptoms subside in hours to days. These reactions may be limited to the sting site, or they may spread across a larger area or entire limb.


Mild sting reactions cause minor symptoms such as a welt, redness, itching, blistering, and being warm to the touch. The pain usually lasts only a few hours. 2


Moderate sting reactions come with the same symptoms as a mild sting reaction, but redness and swelling can continue to expand for up to 10 days. 2

Mild and moderate sting reactions can be treated at home. Learn how to treat a bee sting.

Understanding Bee Stings & Allergic Reactions 2
After being stung on the temple, my eye proceeded to swell shut for several days. This is an example of a moderate reaction.

Systemic Reactions

Systemic reactions are full body allergic reactions to an allergen such as peanuts, shellfish or bee venom. Whereas mild and moderate reactions affect only the localized sting site (like a hand or arm), systemic reactions impact body systems not involved in the sting location, like the respiratory system.


To better understand the difference between a mild or moderate reaction and a systemic reaction, we need to understand a little physiology behind a bee sting.

Mild and moderate reactions can happen with any sting, even the first time someone has been stung.

Systemic reactions, however, can only happen after someone has been exposed to bee venom by being stung in the past. You cannot have an allergic reaction to a substance the body has never encountered. This is because the body has to become sensitized, or sensitive to bee venom, by being exposed to it on one or more encounters, and determining it to be a threat. When the body has become sensitized to bee venom, it will have produced antibodies to respond to future stings. 11 Antibodies are defensive proteins that serve to strengthen the immune system by attacking the allergen (in this case bee venom), should the body become exposed to it again. 12

Once the body is sensitized (or the immune system has become sensitive to) bee venom, the next time someone is stung they will have an allergic reaction. 12

The subsequent allergic reaction to a bee sting may be a mild one. However, around 3-5% of the population develops an overly sensitive immune system and will have an anaphylactic response to bee stings. 12

Because it generally takes more than one bee sting for the body to determine bee venom to be a threat, an individual could end up allergic to bees at any time. Some may become allergic to bees in their first season, while others may not become allergic for several decades, yet others may never become allergic at all. On average, most beekeepers become sensitized to bee venom in less than 18 months 17. Don’t assume if you are in your second year beekeeping that you are immune to bees, sensitization can occur anytime, even after decades of beekeeping.


Anaphylaxis, also known as anaphylactic shock or a severe allergic reaction, is a systemic allergic reaction that can be fatal.

As we explored earlier, anaphylaxis can happen anytime, even after someone has received hundreds of stings over many decades. Anaphylaxis can also be brought upon by multiple stings at once, such as when someone is attacked by Africanized honey bees.


Anaphylactic reactions may be uniphasic or biphasic. Uniphasic reactions are those with an immediate response to a sting and continue to worsen until medical treatment is received.

Biphasic reactions have mild symptoms to start, which is followed by a period with no symptoms, then increasing symptoms to include respiratory and/or blood pressure problems. These blood pressure and/or respiratory symptoms can start up to 36 hours after a sting. 15

Symptoms of anaphylaxis include one or more of the following 14:

  • Hives
  • Mouth and/or tongue swelling
  • Difficulty breathing
  • Asthma like symptoms
  • Chest and/or throat tightness
  • Weak and/or rapid pulse
  • Low blood pressure
  • Nausea
  • Vomiting
  • Stomach cramps
  • Dizziness
  • Loss of consciousness
  • Feeling of impending doom
  • Death

Anaphylaxis can also lead to heart attack and miscarriage. These symptoms may be immediate or present as long as 36 hours after a sting.

Note: These symptoms can mimic an asthma or anxiety attack. If you were stung by a bee and develop any of these symptoms, call 911 immediately. Anaphylactic reactions can quickly worsen and lead to unconsciousness and death. Immediate medical treatment is necessary, and emergency responders need to be contacted before the possible loss of consciousness. It is better to call for help and not need it, than not call and die!

Beekeepers At Risk

For most beekeepers, the thought of getting a serious allergic reaction to a bee sting is far from the focus of their attention. Experienced beekeepers will tell you that honey bees are generally docile and seldom sting unless provoked. But for keen beekeeper Simon Cavill (55) a seemingly innocuous sting led to a potentially life-threatening allergic reaction.

“I started beekeeping 13 years ago and had been stung plenty of times before with no real side effects,” said Simon, who lives with his wife and two children near Basingstoke, Hampshire.

“Then one day, I was beekeeping as usual and was stung by a honey bee. This wasn’t that much of a shock as it comes as part of the territory. However, unlike a normal localised reaction, I started to come out in hives and a rash all over my body.”

Unbeknownst to Simon, he had actually suffered a severe and potentially fatal anaphylactic reaction.

Beekeepers are at a higher risk of having a systemic allergic reaction, or anaphylaxis, to bee stings. Most people only get stung once or twice in their life. Simply put, beekeepers are stung more frequently than most people 19. As we discussed previously, it takes multiple exposures to bee stings to develop an allergy. Other factors that put a beekeeper at risk for a serious reaction include:

  • Female gender
  • Family member with a bee venom allergy
  • More than 2 years of beekeeping
  • Atopic disease (asthma, eczema, hay fever) 7, 17
  • Premedication with an antihistamine (ie Benadryl or diphenhydramine) before attending to hives 15

Having an atopic disease increases the risk of a serious allergic reaction three-fold when one disease is present, and eleven-fold when two or more are present. 18 Those that have nasal or eye symptoms when working hives, such as runny nose or watery eyes, also are at a significantly higher risk of a serious allergic reaction when stung. 20

Common Beekeeper Myths


Or any variation thereof, like:

  • The more I am stung, the safer I’ll be
  • I don’t react to bee stings because I am used to them
  • The more I am stung, the better my allergy resistance will be
  • I “pretreat” myself in the spring with bee venom
  • I’ve built up a resistance to bee stings
  • I can’t be allergic to bees, I’ve had hundreds of stings over the years
  • I’ve been a beekeeper for decades, I can’t be allergic to bees
  • I’ve never had an reaction to stings, so I am not allergic


Unfortunately, these comments are very common on social media, forums, and beekeepers blogs. We covered why these statements are incorrect under “What causes a systemic reaction?”, but if you need more evidence:

The number of stings per year had no effect on sensitization rate. … beekeepers developed sensitization to bee venom in <18 months. 20

Simply put, no matter how many stings a beekeeper has received, and no matter how long a beekeeper has been beekeeping, an allergic or anaphylactic reaction could happen at any time following a bee sting.

Final Thoughts

Please understand that this article is not meant to scare anyone, or dissuade anyone from becoming a beekeeper. Anaphylactic reactions are uncommon. However, knowledge is incredibly important and could be life saving. About 50 people die each year in the United States from bee stings. Many more people die in car accidents, and we all know this, but we all still drive. By understanding what could happen after a bee sting and the symptoms to watch for, you will know when to seek medical attention. It is my honest intent to educate, not to scare. Being a paramedic, I know first hand how quickly a bee sting could become life threatening, yet I continue to keep bees and do my best not to get stung, however, it is inevitable.


  1. Golden, David B.K. “INSECT STING ANAPHYLAXIS.” National Center for Biotechnology Information, 31 Aug. 2007.
  2. Bee Sting.” Mayo Clinic, Mayo Foundation for Medical Education and Research, 10 Aug. 2017.
  3. Bee Sting.” Mayo Clinic, Mayo Foundation for Medical Education and Research, 10 Aug. 2017.
  4. Schumacher, Michael J, et al. “Rate and Quantity of Delivery of Venom from Honeybee Stings .” The Journal of Allergy and Clinical Immunology.
  5. Zolfagharian, Hossein, et al. “Honey Bee Venom (Apis Mellifera) Contains Anticoagulation Factors and Increases the Blood-Clotting Time.” National Center for Biotechnology Information, 28 Dec. 2015.
  6. Chen, Jun, et al. “Melittin, the Major Pain-Producing Substance of Bee Venom.” National Center for Biotechnology Information, June 2016.
  7. Galli, Stephen, et al. “IgE and mast cells in allergic disease.” National Center for Biotechnology Information, 4 May 2012.
  8. K, Zuh, et al. “Phospholipase A2 activity in salivary glands and saliva of the lone star tick (Acari: Ixodidae) during tick feeding.” National Center for Biotechnology Information, 4 July 1998.
  9. Bortolotti, Laura, and Cecilia Costa. Neurobiology of Chemical Communication. CRC Press/Taylor & Francis, 2014, National Center for Biotechnology Information.
  10. More, Daniel. “Understanding Sensitization and True Allergy.” Verywell Health.
  11. Anaphylaxis: MedlinePlus Medical Encyclopedia.” MedlinePlus, U.S. National Library of Medicine.
  12. Bee Venom and the Chemistry of OUCH!” Bee Culture, 27 June 2016.
  13. Golden, David. “Insect Sting Anaphylaxis.” National Center for Biotechnology Information, 31 Aug 2007.
  14. Kinoshita, Hirohisa, et al. “Incidence and characteristics of biphasic and protracted anaphylaxis: evaluation of 114 inpatients.” National Center for Biotechnology Information, 19 May 2014.
  15. Huissoon, Aarnoud P., et al. “Risk factors for systemic reactions to bee venom in British beekeepers.” Annals of Allergy, Asthma and Immunology, Elsevier Inc.
  16. Celikela, S. “Bee and Bee Products Allergy in Turkish Beekeepers: Determination of Risk Factors for Systemic Reactions.” ScienceDirect, Academic Press, 6 Jan. 2009.
  17. Ewan, Pamela. “Venom Allergy.” National Center for Biotechnology Information, 2 May 1998.
  18. Kalogeromitros, et al. “Pattern of Sensitization to Honeybee Venom in Beekeepers: A 5-Year Prospective Study.” Ingenta, 1 Sept. 2006.
  19. Annila, Ilkka t, et al. “Bee and Wasp Sting Reactions in Current Beekeepers.” Annals of Allergy, Asthma and Immunology, Elsevier Inc.
  20. Anaphylaxis. “Our New Allergy Awareness Campaign Urges People to ‘Bee Resistant’ This Summer.” Anaphylaxis Campaign, 6 Aug. 2018.

This site uses Akismet to reduce spam. Learn how your comment data is processed.

This site uses Akismet to reduce spam. Learn how your comment data is processed.