Anaphylaxis is a life-threatening, severe systemic hypersensitivity reaction that rapidly causes symptoms in multiple organs (skin/mucous membranes, respiratory system, circulatory system, digestive system, etc.). Specifically, it is diagnosed when respiratory distress, wheezing, hypotension, impaired consciousness, and gastrointestinal symptoms (vomiting, abdominal pain, etc.) rapidly appear, in addition to skin symptoms (hives, flushing, edema, etc.).
Since it can progress in a short time,Noticing it early and responding appropriately in a timely manner.is important.

The following symptoms:Food, medicine, bee stingsand then suddenly appears.

Hives, itching, swelling of the face or lips
Difficulty breathing, wheezing, voice changes
To feel weak, to sway, to be dazed
・Severe abdominal pain, nausea, vomiting

👉 There are also cases of anaphylaxis that do not present with skin symptoms.
If you suddenly experience shortness of breath or dizziness, do not hesitate to seek medical attention.

Common causes: shrimp, pills, bees
Food (eggs, milk, wheat, peanuts, tree nuts, shrimp/crab, etc.)
・Medications (antibiotics, antipyretic analgesics, contrast agents, etc.)
・Bee stings (wasps, hornets, etc.)

Bee stings,If you have had a strong reaction in the past, you are more likely to have a severe reaction if you are stung again.is known.

Time until symptom onset
Food: a few minutes to 2 hours
・Medicine: a few minutes to 1-2 hours
Bee sting: Can progress rapidly within minutes

If anaphylaxis is suspected
① 119 emergency call
② Use your epinephrine auto-injector (EpiPen) without hesitation
③ Maintain a relaxed posture (slumped → lie on back with legs raised, nausea → lie on side)
④ Stay close and inform the paramedics of the situation.

👉 The sooner adrenaline is administered, the more effective it is.
Antihistamines and steroids have a slow onset of action, are "adjunctive" treatments, and are not a substitute for adrenaline.
It is sometimes used to alleviate skin symptoms (such as itching and hives) and theoretically to prevent biphasic reactions, but it has no effect on improving severe symptoms such as acute airway obstruction and hypotension.

About the EpiPen (epinephrine auto-injector)
・Use on the outer thigh. This is an intramuscular injection.

📱 EpiPen Official App(My Epi)

📱 EpiPen Official App(My Epi)
How to use video
Practice Mode
Expiration date management
and is very convenient for guardians.
Feature: Emergency Voice Navigation
In the unlikely event of anaphylaxis, this is an audio guide on how to administer the anaphylaxis adjunctive treatment.
In case of an emergency, you can also call an ambulance through the 119 dialog after the video ends.
You can also learn in advance through videos.

🧺Everyday preparedness

Identify causative foods and medications.
Share information among school, kindergarten/daycare, and family.
・Regularly review how to use the EpiPen
・How to communicate when eating out and checking food labels

References

Japanese Society of Allergology Anaphylaxis Guidelines (2022)
・JAMA 2024 "Food Allergies and Anaphylaxis"
・Allergology International 2023 "Epidemiology of Anaphylaxis in Japan"
・AHA First Aid Guidelines 2024
・JACI / Ann Allergy 2023–2025 (Latest Findings on Epinephrine Therapy)

Neffy (nasal adrenaline) has been approved in Japan.

September 19, 2025, anaphylaxis adjuvant therapy agent
Nefy® Nasal Spray 1mg / 2mg has been approved in Japan.

What kind of medicine?

A new type of therapeutic drug that administers adrenaline nasally
Anaphylaxis due to bee venom, food, or drugsAdjunctive therapy
・Individuals with a history of anaphylaxis or those at high riskis applicable

Features

Administered with one push, no needle required.
・Under 30kg → 1mg
・Over 30kg → 2mg

Points to note

・The first choice remains "epinephrine auto-injector (EpiPen)" as before.
Nefie is considered "supportive care."
・Prescription forDoctor registration is required(Conditions of Approval)

Price (Drug Price)

・1mg: 22,975 yen
・2mg: ¥24,672

Nefy Nasal Spray Manufacturing and Sales Approval Obtained (Alfresa Pharma Official Release)
PR TIMES: Notice of Approval for Nefi Nasal Spray 1mg/2mg
Nefie nasal spray drug price and usage (New Drug Information Online)