What Leptin Is. Leptin is a hormone secreted by adipose tissue (fat cells) that tells you youâre full. (Its opposite hormone is called ghrelin, which tells you youâre hungry. You can remember this because the word ghrelin sounds like a stomach growling.) Because leptin is secreted by fat cells, you produce more leptin as your weight increases.
Epinephrine is the most effective treatment for anaphylaxis, and the shot should be given right away (usually in the thigh). If youâve had an anaphylaxis reaction before, you should carry at least two doses of epinephrine with you at all times.
For an anaphylactic reaction to occur, you must have been exposed in the past to the substance that causes the reaction, called the antigen. This is called sensitization.. 1  A bee sting, for example, may not cause an allergic reaction the first time. 2  Another bee sting may produce a sudden, severe allergic reaction known as anaphylaxis or anaphylactic shock.