Anti-food allergy medicine

Currently, no drug can 100% prevent food allergy attacks. All drugs on the market labeled "anti-food allergy" are essentially either preventive drugs taken in advance to reduce the probability of attacks, or therapeutic drugs to relieve symptoms and rescue critical situations after an allergic attack. All drugs cannot replace the active avoidance of allergens.

Last week, I went to eat Sichuan hot pot with my best friend who has a history of mango allergy for 7 years. The first thing she did when she sat down was not to get the menu, but to take out a small cloth bag the size of a palm, with three things stuffed in it: a tablet of loratadine, an epinephrine pen, and a small card with the words "Mango/cashew nut allergy, if I am unconscious, please call 120 and contact xxx". I laughed at her for being too nervous, and she rolled her eyes: "Last time I went to a newly opened Thai restaurant with my friends. I thought the mangoes in the green mango salad had been picked clean. After two bites, my mouth became numb. If I hadn't taken a pill in advance, I might have gone to the hospital on the spot. ”

There has been a long-standing debate in clinical practice about whether to take antihistamines in advance to prevent allergies. Most general internal medicine doctors will remind patients with mild symptoms: If you go to a meal with uncertain ingredients, taking a second-generation antihistamine half an hour in advance can reduce the probability of rashes and skin itching. After all, second-generation antihistamines have very low side effects, most of them will not make you sleepy, and there will be no long-term damage. However, most specialists in the allergology department do not recommend this. When I accompanied a friend to a follow-up visit, the director made it clear: Taking medicine in advance is likely to mask the early symptoms of allergy. The numbness in your mouth will stop immediately after you take one bite. But after taking the medicine, the numbness in your mouth will be lighter. If you take two more mouthfuls, it may directly progress to laryngeal edema, which will be troublesome to rescue at that time.

Nowadays, there are mainly two types of antihistamines that are commonly used for early prevention. One type is the second-generation antihistamines just mentioned, such as loratadine, cetirizine, and desloratadine. The effectiveness is about 70%. They mainly block the histamine release pathway and can prevent mild rashes, itching, and sneezing. They are completely useless against severe respiratory and cardiovascular allergic reactions. The other type is mast cell membrane stabilizers, such as sodium cromoglycate, which generally need to be used 1-2 days in advance. If you are traveling to other places or eating out for several days in a row, you are not sure whether you will encounter cross-contaminated allergens. You can use them in advance to make mast cells less likely to "explode" and release much less allergic mediators. However, the efficiency is even lower, about 60%. Several friends with allergies around me said that it seems useless after using them, and the individual differences are very large.

Oh, by the way, be sure to understand that these preventive and symptom-relieving drugs are not life-saving. There was a news story last year. A young man had a severe seafood allergy. He went to a barbecue with his friends and thought that he would be fine if he took loratadine in advance. After trying two bites of grilled squid, he was out of breath within half an hour. When he was sent to the hospital, his larynx was swollen and he was suffocating, and he was admitted to the ICU. When you really encounter a severe allergic reaction - you feel that your throat is tight, you can't breathe, you are dizzy and you can't stand, and you have large and continuous wheals on your body, the only first-choice life-saving drug is epinephrine, which is the kind of pre-filled epinephrine pen that pricks the outside of the thigh.

Nowadays, many people still say that desensitization injection is a "magic medicine to cure allergies". Is it considered an anti-allergy medicine? This is more controversial. Those who support it believe that after all, after taking allergen immunization preparations for 3-5 years continuously, about 70% of people can greatly improve their tolerance to specific allergens. Some people with mild symptoms will not even be allergic to a small amount of exposure in the future, which is equivalent to fundamentally reducing the possibility of attacks. But those who oppose it think that this is not a "preventive medicine" at all. First of all, it is only effective against specific allergens. If you have taken a desensitization shot for dust mites, should you be allergic to mangoes or not? ； Secondly, the entire course of treatment takes two to three years, is expensive and troublesome, and may induce severe allergic reactions in people with severe allergies. It is not a "preventive medicine" that can be used casually.

By the way, don’t believe those “all-you-can-eat anti-allergy pills” and “seafood mango nemesis” sold by Internet celebrities. I was curious and checked out a particularly high-selling product. The ingredient list is vitamin C + calcium gluconate, and some secretly add excessive hormones. It is true that you will not be allergic temporarily if you eat it, but long-term consumption will lead to osteoporosis and reduced immunity. It is just a scam.

There are many friends with allergies around me, ranging from mild symptoms such as itchy lips after eating mangoes to severe symptoms such as being admitted to the ICU if you touch a little cashew nut. When we all gathered together to chat, the most common point we reached consensus on was: Don’t treat medicine as a golden ticket to avoid death. If you can ask in advance if there are any allergens in the ingredients, try to ask. If you can, try not to eat something you are not sure about. The medicine is to be used as a cover, not for you to eat blindly. If you really have a history of severe allergies, you must discuss with your attending doctor what medicine to prepare and how to use it. Everyone's allergic reaction is different, and other people's experiences may not apply to you. Don't take medicine by yourself.