Hi, Welcome to Healthcaremagic, Sever life threating reaction to bee / spider bite is one type of anaphylactic reaction, in which there is massive release of inflammatory mediators occurs in one s body due to bee / spider toxin. This will lead to variety of symptoms which are as follows, -difficulty in breathing or noisy breathing -swelling of the tongue -swelling / tightness in the throat -difficulty talking and / or a hoarse voice -wheezing or persistent coughing -loss of consciousness and / or collapse -Abdominal pain or vomiting (when associated with an allergic reaction to an insect sting or bite) Above mentioned signs/symptoms may have to be treated with injection of adrenaline (epi-pen contains adrenaline) in order to save person s life. So, what I suggest you is first re-memorize your bite incidence and if you found that you had suffered from at least 2 of above symptoms (one including last one) than it is must for you to carry epi-pen with you otherwise there are less chances that you may need it. But, as you know there are thousands of insects in world and person not allergic to one may be allergic to another as different spices have different type of toxins. So, it is safe for you to carry epi-pen with you when you are at elevated risk for exposure to the insects (like during camping, visiting beaches etc). Regarding incidence of your cousin, the sever allergic reaction- anaphylactic reaction usually does not run in families, so forget about it. Don t worry, just be cautious. Hope this will help you, take care. -Dr. Vishal Vadgama (MD)