💉 Appointments for “Urticaria (Hives)” are available exclusively at the Shinjuku branch dermatology outpatient clinic.
📖 What You’ll Gain from This Article
- 💡 The 7 types of urticaria (hives) explained
- 🎯 Identify the cause of your hives
- 💊 Learn about current treatment approaches and commonly used medications
- 🏥 Understand when you should see a doctor
⚠️ Risks of Not Reading This
- ❌ Symptoms may become chronic, causing discomfort for months
- ❌ Recurring episodes with no identified cause
- ❌ Risk of serious complications such as anaphylaxis
- ❌ Potential impact on work and school life…
🔥 Are You Experiencing These Symptoms?
😰 “My skin suddenly became itchy all over, with red rashes appearing…”
😓 “What causes hives? How do I get better?”
💭 Many people share these concerns. Hives typically appear as raised, mosquito-bite-like welts accompanied by intense itching. Left untreated, they can become chronic and persist for weeks or even months… 😱
✨ Don’t worry! This article provides a clear, easy-to-read overview of the causes, symptoms, and treatment options for hives — designed to be read comfortably on your smartphone.
🤔 What Are Hives (Urticaria)?
Hives (urticaria) are a skin condition characterized by swelling in the skin and the formation of wheals (raised welts) across the body.
💡 What are wheals?
Raised, mosquito-bite-like skin lesions. They are related to chemical mediators such as histamine released from mast cells in the skin.
🌟 Key characteristics of hives:
- 🔴 Triggered by a variety of causes including allergies and physical stimuli
- 🔬 A possible link with atopic dermatitis has been noted in recent research
- 🧬 Not contagious and rarely hereditary
- 🏥 Because there are 7 distinct types, identifying the cause at a medical facility is important!
❓ Why Do Hives Occur? A Thorough Look at the Causes
The causes of hives can be broadly divided into exogenous (external stimuli) and endogenous (internal factors).
🌍 Cause ①: Exogenous Urticaria (Often Transient)
The main triggers include food, medications, and physical stimuli.
- 🦠 External antigens: pathogenic bacteria, viruses, pollen, etc.
- 👋 Physical stimuli: friction, pressure, temperature changes
- 💧 Sweat stimulation: perspiration after exercise or bathing
- 🍖 Food: pork, bamboo shoots, food additives, etc.
- 💊 Medications: various pharmaceutical drugs
- 🏃 Exercise: strenuous physical activity
🫀 Cause ②: Endogenous Urticaria (Often Persistent)
The main contributors include stress, fatigue, and allergies.
- 🧪 Sensitization: hypersensitivity of the immune system
- 🦠 Infection: bacterial or viral infection
- 😰 Fatigue and stress: among the most common causes in modern life
- 🍔 Food: similar to exogenous causes
- 💊 Medications: aspirin, ACE inhibitors, etc.
- 🧬 IgE: antibodies involved in immune responses
- 🏥 Underlying conditions: hematopoietic disorders, genetic deficiencies, etc.
💡 Key point: Hives are not contagious and are rarely hereditary!
😣 What Are the Symptoms of Hives?
Typical symptoms of hives include:
- 🔴 Raised, mosquito-bite-like welts (wheals)
- 😖 Accompanied by intense itching
- 📏 Varying in size from about 1 cm to several tens of centimetres
- ⏱️ Can spread across the body within a few hours
- ⏰ Usually resolve within a few hours
⚡ Acute Urticaria vs. Chronic Urticaria
- ✅ Acute urticaria: resolves after a single episode (in most cases)
- ❌ Chronic urticaria: recurs over weeks or months (requires attention!)
🔬 A Complete Guide to the 7 Types of Hives
Hives can be classified into 7 types, each with its own characteristics and treatment approach.
| 🏷️ Type of Urticaria | ✨ Characteristics |
|---|---|
| ⚡ Acute Urticaria | ・Resolves within 1 month ・Often caused by bacterial or viral infection |
| 🔄 Chronic Urticaria | ・Recurs for more than 1 month ・Often has no identifiable cause |
| 🤲 Physical Urticaria | ・Triggered by physical stimuli such as friction, pressure, temperature changes, or sunlight |
| 💦 Cholinergic Urticaria | ・Occurs when sweating (e.g., after exercise or bathing) ・Wheals are small, 1–4 mm in size ・More common in younger individuals |
| 🥜 Allergic Urticaria | ・Reaction to specific allergens (food, medications, insects) ・Involves IgE antibodies |
| 💊 Intolerance | ・Triggered by aspirin, contrast agents, food additives, etc. ・IgE is not involved |
| 😮 Angioedema | ・Sudden swelling of areas such as the lips or eyelids ・Subsides over 2–3 days ・Itching is minimal |
⚠️ Important: Self-diagnosing the type of hives can be risky! Because treatment varies by type, always seek an accurate diagnosis at a medical facility.
🏥 How Are Hives Diagnosed?
The key to diagnosing hives is identifying the type and determining the underlying cause.
🔍 The Diagnostic Process
- 👨⚕️ Medical interview: Detailed discussion of symptom characteristics and history
- 👀 Visual examination: Assessment of the appearance of the rash
- 🩸 Blood tests: Conducted as needed (some clinics perform these on a regular basis)
💡 Key point: The type of hives can often be determined based on the characteristics and progression of symptoms.
⚠️ However, repeated blood tests can place a significant burden in terms of time and medical costs, so we create the most appropriate testing plan for each individual patient.
💊 How Are Hives Treated? A Thorough Explanation
Treatment for hives proceeds in 2 stages.
🎯 Step ①: Identify and Remove the Cause
The first step is to have a doctor identify the cause and any aggravating factors.
💊 Step ②: Pharmacological Treatment
Once the cause has been addressed, treatment begins with antihistamines or anti-allergic medications!
- 🧴 Topical medications: applied directly to the skin
- 💊 Oral medications: taken by mouth (generally considered more effective)
- 💉 Injections: for severe cases
🌟 Daily Lifestyle Tips
- 😌 Minimize fatigue and stress as much as possible
- 🥗 Choose fresh foods
- 🚫 Limit preservatives and additives
💊 What Medications Are Used for Hives?
The first-line treatment for hives is antihistamines or anti-allergic medications.
🧪 Why Do These Medications Work?
Hives occur when histamine released from mast cells acts on blood vessels and nerves, producing symptoms.
- 🔬 Allergens attach to mast cells
- 💥 Chemical mediators such as histamine are released
- 🔴 Blood vessel dilation + itching occur
➡️ Antihistamines block the action of histamine!
💊 Effects by Medication Type
- ✅ Oral medications and injections: generally more effective
- ⚠️ Topical medications: provide only modest itch relief and are not expected to produce a significant effect
😴 About Side Effects
Side effects of older medications include:
- 😪 Drowsiness
- ⚠️ Worsening of symptoms in benign prostatic hyperplasia or glaucoma
✨ Rest assured — medications developed in recent years tend to have fewer side effects.
💡 Additionally, herbal (Kampo) medicines and immunomodulatory agents may sometimes be used as supplementary treatments.
❓ Frequently Asked Questions About Hives
Hives and eczema may look similar, but their symptoms and duration are quite different!
🔴 Hives (Urticaria):
・Onset is sudden
・Symptoms appear and disappear across the body
・Typically resolves within a few hours
・Treatment: anti-allergic medications
🟠 Eczema:
・Progresses gradually over days to weeks
・Symptoms persist in specific areas only
・Lasts hours to days
・Treatment: topical steroids
⚡ Acute urticaria: The rash typically fades within less than a day and resolves within a few days in most cases.
🔄 Chronic urticaria: Symptoms repeatedly appear and disappear over weeks or months, making treatment a longer process.
😌 In most cases, hives are unrelated to internal organ disease, so there is no need to worry.
However, in some cases, the following conditions may be present in the background:
・🦋 Thyroid disease
・🦠 Viral hepatitis
・🏥 Gastritis, etc.
💡 If you are concerned, please consult a doctor. Testing can help clarify the situation.
🏥 For Hives Treatment in Tokyo — IC Clinic Shinjuku
With the right diagnosis and appropriate treatment, hives can be managed and improved!
✨ Features of IC Clinic:
- 👨⚕️ Experienced specialist physicians on staff
- 🏥 Diagnosis and treatment based on up-to-date medical knowledge
- 💬 Individualised consultations tailored to each patient
- 🌟 A welcoming atmosphere for patients of all ages
⚠️ Please seek advice promptly if you experience any of the following:
- 😣 Itching so severe you cannot sleep
- 🔄 Recurring episodes
- 😰 Unable to identify the cause
- 💼 Symptoms affecting daily life
💉 Appointments for “Urticaria (Hives)” are available exclusively at the Shinjuku branch dermatology outpatient clinic.
📚 For Those Who Want to Learn More: A Medical Overview of Hives
🔬 The Mechanism of Mast Cells
Here we explain mast cells, which play a key role in the development of hives.
- 🛡️ Under normal conditions, they form part of the immune system that protects the body from external threats
- 💥 When stimulated, they release substances including histamine, leukotrienes, and prostaglandins
- 🔴 These substances cause blood vessel dilation, increased vascular permeability, and itching
🧬 IgE Antibodies and Allergic Reactions
The mechanism behind allergic urticaria:
- 🔬 Sensitization: IgE antibodies are produced upon first exposure to an antigen
- 🧲 Binding: IgE antibodies attach to the surface of mast cells
- ⚡ Re-exposure: Contact with the same antigen again triggers an immediate reaction (Type I allergy)
👶👵 Characteristics of Hives by Age Group and Sex
👶 Childhood (Ages 0–12)
- 🦠 More likely to develop alongside an infection
- 🥛 Food allergies are a common cause (eggs, milk, wheat, etc.)
- ⚡ Symptoms tend to appear rapidly
- ✨ However, recovery is also quick!
🎓 Adolescence and Young Adulthood (Ages 13–25)
- 💦 Peak age for cholinergic urticaria (triggered by sweating)
- 😰 Increase in stress-related urticaria (from exams, club activities, relationships)
- 👩 In women, symptoms may fluctuate with the menstrual cycle
💼 Adulthood (Ages 26–64)
- 🔄 An age group prone to developing chronic urticaria
- 💼 Workplace stress and exposure to chemicals can be contributing factors
- 💊 Increase in drug-induced urticaria (from medications for hypertension, diabetes, etc.)
👵 Older Adults (Age 65 and Over)
- 🏥 Underlying conditions are often the cause (thyroid disorders, diabetes, kidney disease)
- 🧴 Reduced skin barrier function leads to greater sensitivity to stimuli
- 💊 Risk of interactions between multiple medications
🌸❄️ Managing Hives by Season
🌸 Spring (February–May)
- 🌲 Watch out for cedar pollen-related urticaria
- 😰 Stress from new life changes
- 🌡️ Physical urticaria from temperature fluctuations
🛡️ Tips: Wear a mask and hat, change clothes and wash hands after coming indoors, manage indoor humidity
☀️ Summer (June–August)
- 💦 Sweat-induced urticaria
- ☀️ Solar urticaria
- ❄️ Temperature differences from air conditioning
🛡️ Tips: Wipe sweat away frequently, use sunscreen, keep air conditioning set within 5°C of the outside temperature
🍂 Autumn (September–November)
- 💧 Reduced skin barrier function due to dryness
- 🦐 Seafood and nut allergies
⛄ Winter (December–February)
- 🧊 Cold urticaria (from cold air or water)
- 🔥 Dryness from indoor heating
🛡️ Tips: Use moisturiser, maintain indoor humidity at 50–60%, avoid sudden temperature changes
📊 Severity of Hives and Treatment Steps
🟢 Mild
- Symptoms: small rash, mild itching
- Duration: within a few hours
- Treatment: second-generation antihistamines
🟡 Moderate
- Symptoms: widespread rash, moderate itching
- Duration: 24–48 hours
- Treatment: increased dosage of antihistamines
🔴 Severe
- Symptoms: generalised rash, intense itching, angioedema
- Duration: several days to chronic
- Treatment: corticosteroids, immunosuppressants
🚨 Very Severe (Emergency)
- Symptoms: difficulty breathing, drop in blood pressure, impaired consciousness
- Response: Call emergency services (119) immediately! Use an epinephrine auto-injector (EpiPen)
🥗 Diet Tips for Hives Prevention
🚫 Foods to Avoid
- 🧀 High in histamine: cheese, wine, fermented foods, dried fish
- 🍅 Histamine-releasing: tomatoes, aubergine, bamboo shoots, Japanese mountain yam
- 🎨 Artificial additives: colorings, preservatives, artificial sweeteners
✅ Foods to Include in Your Diet
- 🐟 Omega-3 fatty acids: oily fish, flaxseed oil, walnuts
- 🍊 Vitamin C: citrus fruits, strawberries, broccoli
- 🧅 Quercetin: onions, apples, green tea (a natural antihistamine!)
😌 Managing Stress to Help Prevent Hives
🧘 Relaxation Techniques
- 🌬️ Deep breathing: 10 minutes of diaphragmatic breathing per day
- 💪 Progressive muscle relaxation: tense and then release muscles throughout the body
- 🧘 Meditation: mindfulness meditation
😴 Quality Sleep
- ⏰ Maintain a regular bedtime and wake-up time
- 📱 Avoid smartphones and television before bed
- 🌡️ Keep your bedroom at a comfortable temperature and humidity level
- ☕ Limit caffeine and alcohol intake
🏃 Moderate Exercise
- 🚶 Walking or swimming 3–4 times per week
- 🧘 Yoga or tai chi
- 🚿 Shower promptly after exercise (to avoid irritation from sweat)
🏥 When to See a Doctor!
If you experience any of the following symptoms, please seek medical attention promptly:
🚨 Symptoms Requiring Urgent Attention
- 😮💨 Difficulty breathing
- 😵 Altered or impaired consciousness
- 💔 Drop in blood pressure
- 😨 Swelling of the lips, tongue, or throat
➡️ Call emergency services (119) immediately — this may be anaphylaxis
⚠️ See a Doctor Soon
- 🔄 Symptoms persisting for more than 1 week
- 😣 Itching so severe you cannot sleep
- 💼 Symptoms affecting your daily life
- ❓ Cause is completely unknown
💡 Summary: Hives Can Be Managed with the Right Treatment
Hives are a complex, multifactorial condition, but with appropriate diagnosis and treatment, symptoms can be managed and improved.
✨ Key points:
- 🔍 Identifying the type and cause is the top priority
- 💊 Antihistamines are the first-line treatment
- 🥗 Diet and stress management also play an important role
- 🏥 Avoid self-diagnosis — consult a specialist
- 🌟 There is a treatment approach suited to each individual patient
💬 At IC Clinic, we provide diagnosis and treatment based on up-to-date medical knowledge and are fully committed to supporting every patient’s symptom management and improved quality of life.
😊 Hives are a condition you do not have to face alone. With the right medical support, managing your symptoms and enjoying a comfortable daily life is within reach.
🌟 If you have any concerns at all, please feel free to get in touch!
👨⚕️ Supervising Physician
Dr. Kota Takakuwa
Career History
- 2009 — Graduated from the Faculty of Medicine, The University of Tokyo
- 2009 — Tokyo Teishin Hospital
- 2012 — Tokyo Metropolitan Police Hospital
- 2012 — The University of Tokyo Hospital
- 2019 — Appointed Clinical Director at our clinic
Dr. Masaki Sato
Qualifications
Certified Specialist in Orthopaedic Surgery, Japanese Orthopaedic Association
Career History
- 2010 — Graduated from the School of Medicine, University of Tsukuba
- 2012 — The University of Tokyo Hospital
- 2012 — Tokyo Teishin Hospital
- 2013 — Yokohama Rosai Hospital, Japan Organization of Occupational Health and Safety
- 2015 — National Center for Global Health and Medicine, then joined our clinic
