Often, "epinephrine pens" are covered in first aid courses.
An epinephrine injection pen is an automatic injection device that generally requires a prescription. People who know they have a severe allergic reaction often carry an epinephrine pen and know how and when to use it. If you have received relevant training and the laws in your area allow it, you can help patients administer injections in an emergency.
How to use an epinephrine pen
Follow the instructions on the pen. When holding the pen in a fist, make sure not to touch either end of the pen as the needle can pop out of one of the ends. You can inject through clothing or directly into your skin.
Remove the safety helmet.
Aiming at the outside of the patient's thigh (between the hip and knee joints), press the injection end of the pen firmly against the muscle. Note: Inject vertically.
Press and hold the injection pen still for about 10 seconds (there are also 3 seconds, please read the instructions on the product carefully).
Pull the pen out vertically, making sure not to touch the end that was injected into the patient's thigh with your fingers.
The patient receiving the injection or the person giving the injection should rub the injection site for about 10 seconds.
Please record the injection time. Give the pen to first aid personnel for proper disposal.
If the patient does not improve or it takes more than 10 minutes before senior ambulance personnel arrive at the scene, 120 should be called. Consider giving another dose of medication, if available.
But, do you know the history of adrenaline? Do you know how the epinephrine pen came to be?
Let’s review it today.
The discovery and use of epinephrine
Epinephrine is the main hormone of the adrenal medulla. Its biosynthesis mainly involves the formation of norepinephrine in the medullary chromium cells, and then further converts norepinephrine into norepinephrine through the action of phenylethylamine-N-methyltransferase. Methylation to form epinephrine. It is a hormone naturally secreted by the human body. When a person experiences certain stimuli, this chemical is secreted, which can speed up breathing, accelerate heartbeat and blood flow, and dilate pupils, providing more energy for physical activities and making reactions faster.
Like other discoveries in the history of science, the discovery of adrenaline is also a story full of legends, twists and turns and inspiration.
In 1859, British doctor Henry Salter reported that "asthma is cured immediately by a sudden alarm or a brief and severe stimulation." This may be the world's first description of the therapeutic effects of epinephrine.
In 1894, British physician George Oliver and British physiologist Edward Schafer used handmade laboratory instruments made of steel hooks to observe the effective effects of adrenal marrow extract on the heart rate and blood pressure of animals. . Their conclusions attracted the attention of the scientific community.
The next step for Oliver and Schaefer is to challenge the adrenal gland extract to determine the physical and biochemical properties of the substance. Their work also laid the perfect foundation for John Jacob Abel, a biochemist and pharmacologist at Johns Hopkins University in the United States. In 1899, Abel claimed to have extracted a highly pure active ingredient of adrenaline. However, Abel was challenged by two other scientists who believed that his extract was not as pure, which frustrated Abel. The two challengers were Austrian physician, physiologist and biochemist Otto von Furth and Japanese-American biochemist Jokichi Takamine. Later, Gaofeng Rangji successfully isolated "high-purity, stable, crystalline" epinephrine and named it epinephrine (adrenalin).
In the wake of these results, scientific and medical researchers naturally turned their attention to identifying therapeutic uses for epinephrine. Solomon Solis-Cohen, a clinical professor of medicine in Philadelphia, USA, who first tested asthma and hay fever patients around 1900, reported that oral administration of dry epinephrine relieved symptoms and The mechanism is described as "relaxing vasodolatory ataxia." This finding is consistent with one of the favorite premises of asthma pathophysiology, the vasodilator hypothesis. At that time, asthmatic airway obstruction was attributed to vasodilation and subsequent swelling of the bronchial mucosa. This idea is also supported by the actions of Jesse Bullowa and David Kaplan, who successfully treated asthma patients with subcutaneous injections of pure epinephrine, which made epinephrine a serious Recommended relief medications for asthma attacks.
In 1905, British physiologists William Bayliss and Ernest Starling proposed the idea of a hormone acting as an endogenous messenger, secreted by one organ to influence another. The function of an organ. After considering the effects of adrenaline, he quickly concluded that it must be a hormone. The British physiologist John Langley and the British physician and physiologist Thomas Elliott laid the foundation for the concept of drug receptors. Langley noted that the effects of adrenal extract were comparable to electrical stimulation of sympathetic nerves, and Elliott suggested that epinephrine might be secreted from sympathetic nerve endings. The work of the British chemist George Barger and the British pharmacologist and physician Henry Dale seemed to support this hypothesis. Epinephrine can trigger a contractile response in cats' nerves in vivo to assess sympathetic activity. Brian Melland, a doctor in London, recognized the relationship between epinephrine and sympathetic nerve activity, believing that epinephrine induces bronchial muscle relaxation by targeting the vagus nerve. The concept of epinephrine and other hormones involved in homeostasis was first proposed by American physiologist Walter Cannon and eventually led to theories on internal and external signaling mechanisms and feedback responses.
By this time, the therapeutic potential of epinephrine was widely recognized, and manufacturers began developing synthetic forms of epinephrine. In 1904, German chemist Friedrich Stolz produced the first synthetic hormone by synthesizing the ketone form of epinephrine. In 1906, after further synthesis, mass production became possible. Synthetic epinephrine is more effective than adrenaline extract and has little impact on disease. American physiologist Carl Wiggers demonstrated in 1905 the vasoconstrictive effect of synthetic epinephrine on cerebral blood flow.
However, doctors are still debating which route of administration is best. Parke-Davis & Company manufactured equipment for the conditioning of soluble drugs such as ampoules in 1909. These ampoules improve the accuracy and speed of manufacturing and delivery of soluble drugs by containing a fixed dose of the drug that can be injected subcutaneously in emergency situations. In 1920, Brian Melland published a report in The Lancet endorsing the method of subcutaneous injection of epinephrine. In the report, he published the results of his own case studies, including one of a 30-year-old woman who had a six-year history of asthma and "convulsive attacks... that occurred every night" after epinephrine injections. The symptoms were significantly relieved. Melander also noted the lack of beneficial effects of epinephrine when administered orally.
However, in 1910, George Barger and Henry Dyer discovered that epinephrine could also improve patients' symptoms when used as an aerosol. In 1913, James Adam, author of Asthma and Its Cure, stated that "absorption of medicine from the mucosa of the nose, larynx, or trachea" should be considered an alternative route to epinephrine. By the 1930s, epinephrine nebulizers were readily available, either for use by doctors in hospitals or for patients to take home for self-use because they were safe.
The invention of the epinephrine pen
In the 1970s, biochemical engineer Dr. Sheldon Kaplan first invented an auto-injector for the U.S. military that was filled with a nerve gas antidote to protect soldiers in the event of chemical warfare. The military needed a device that would not react chemically with the drugs contained within it, but also be easy to use in an emergency.
Around the same time, he developed a similar device for civilians, except they were using it against their own enemy: allergies.
What is an allergy? What is an allergic reaction?
The explanation given by the “National Health Commission’s Authoritative Medical Science Popularization Project Communication Network Platform” is:
On December 16, 1890, the famous French physiologist and pathologist Charles Robert Richet (1850.8.26-1935.12.4) successfully used serum injection for treatment for the first time, creating a The first of modern serum therapies. He believes that immunity not only protects the body, but also causes pathological reactions and even death. This reaction is the result of the body's increased sensitivity to antigenic substances and is a manifestation of excessive immunity. He called this phenomenon "anaphylaxis." Richet conducted research by injecting jellyfish venom into dogs. His results broke through traditional concepts and greatly promoted the development of immunology. He also won the Nobel Prize for this.
Afterwards, Kaplan designed and introduced a spring-loaded syringe preloaded with a certain dose of epinephrine. It is designed to be simple to use and can be injected even by a person wearing clothes. Anyone can use it correctly with brief training and does not require any medical expertise.
In 1987, what we now know as the EpiPen—injectable epinephrine combined with a drug and syringe—was approved by the U.S. Food and Drug Administration (FDA).
Although Kaplan's name is listed on the patent, he never received royalties for the invention, which is owned by his employer, Survival Technology Inc.
At this time, EpiPen is still owned by a company called Meridian Medical Technologies.
Meridian Medica, now a subsidiary of Pfizer, still produces a range of other auto-injector devices - including anti-nerve gas pens still used by the military.
In 2007, the American company Mylan acquired EpiPen. A few years later, Mylan’s share of the epinephrine device market has reached an astonishing 90%.
