Acne (Acne Vulgaris) | Dermatology in Hiroo & Ebisu, Tokyo | Yasashii Clinic

Medically Reviewed by: Takafumi Suzuki, MD — Primary Care in Dermatology, Internal Medicine & Allergology; Specialist in Anesthesiology

Written by: Yasumasa Ohno — Business Development & Content Manager, Yasashii Clinic Hiroo Shirokane

Last Updated: April 2, 2026

What You'll Learn in This Article

• What acne vulgaris is — and why adult acne is different from teenage acne

• The four-step mechanism behind every pimple

• Why OTC products often fall short — and what prescription treatments can do

• How to prevent acne scars (post-inflammatory hyperpigmentation and atrophic scarring)

• Practical daily habits for managing acne in Tokyo's urban environment

Acne is the most common skin condition worldwide. While it's often associated with adolescence, adult acne — persistent or new-onset acne in people over 25 — is increasingly prevalent, particularly in individuals with high stress loads, hormonal fluctuations, and exposure to comedogenic cosmetics. Whether your acne is mild, severe, or has already left its mark on your skin, effective treatment options exist — and the earlier you start, the better your outcome.

Table of Contents

1. What Is Acne (Acne Vulgaris)?

Acne vulgaris is a chronic inflammatory skin condition affecting the pilosebaceous units (hair follicle + sebaceous gland). It involves four intersecting pathological processes: excess sebum production, abnormal follicular keratinization (clogged pores), proliferation of Cutibacterium acnes (formerly Propionibacterium acnes), and the resulting inflammatory immune response.

Acne is among the most prevalent skin disorders globally, affecting an estimated 85% of adolescents and a significant proportion of adults. In the Hiroo, Ebisu, and Shirokane areas of Tokyo — where many residents work long hours, manage high-stress careers, and invest significantly in skincare — adult acne is a particularly common concern.

Common Misconceptions

• "Acne means you're not washing your face properly." Over-washing strips the skin barrier and can trigger compensatory sebum overproduction. Hygiene is not the cause.

• "You'll grow out of it eventually." Adult acne beyond the mid-20s does not resolve on its own for many people — and untreated inflammatory acne leaves permanent scars.

• "Just dry out the oil and the acne will go away." Dehydrating the skin without addressing the other three mechanisms (keratinization, bacteria, inflammation) is ineffective and often makes acne worse.

2. Types of Acne — From Comedones to Nodules

Non-inflammatory (comedonal)

• Closed comedone (whitehead): Pore blocked by sebum and keratin, exit closed. No redness.

• Open comedone (blackhead): Oxidized sebum at a widened pore opening appears dark. No inflammation.

Inflammatory

• Papule: A small, firm, raised red bump — immune cells beginning to respond

• Pustule: A papule with visible pus at the surface — neutrophil accumulation

• Nodule: A large, deep, painful lump — severe inflammation extending into the dermis

• Cyst: A deep, pus-filled cavity — the most severe form, highest risk of scarring

"I have an important client presentation tomorrow. And right now — again — I've got two painful cysts along my jawline that I can't cover with makeup. It's been like this for the past ten years. People at work must think I'm not taking care of myself, but I've tried everything."

Acne's impact extends well beyond the skin — it affects confidence, professional life, and mental health in ways that are consistently underestimated by those who don't experience it.

3. Causes: Sebum, Clogged Pores, Bacteria, and Hormones

Androgens and Sebum Androgens (including testosterone and DHEA-S) stimulate sebaceous glands to produce sebum. This explains why acne peaks during puberty, worsens premenstrually, and is associated with conditions like polycystic ovary syndrome (PCOS).

Follicular Hyperkeratinization The inner lining of the follicle sheds keratin cells continuously. When this process is disrupted — by androgens, certain cosmetics, or friction — the excess keratin mixes with sebum and plugs the pore, forming a comedone.

C. acnes Proliferation The anaerobic environment of a blocked follicle allows C. acnes to proliferate. The bacteria produce lipases that break down sebum triglycerides into free fatty acids — triggering innate immune activation.

Inflammation The immune response to C. acnes involves recruitment of neutrophils and macrophages, release of IL-1β, TNF-α, and matrix metalloproteinases — breaking down the follicle wall and causing the redness, swelling, and eventual scarring associated with inflammatory acne.

Adult Acne — Additional Triggers

• Chronic psychological stress (cortisol → androgen cascade)

• Sleep deprivation (reduced skin repair, increased cortisol)

• High-glycemic index diet and dairy overconsumption

• Comedogenic cosmetics or makeup (common in Tokyo's cosmetics-rich environment)

• Mask-wearing friction and occlusion ("maskne")

• Hormonal transitions: perimenopause, stopping oral contraceptives

4. The Mechanism Behind a Pimple

1. Androgen surge → sebaceous gland overactivation → excess sebum

2. Follicular hyperkeratinization → dead cells and sebum accumulate → comedone forms

3. C. acnes proliferation in the oxygen-poor blocked pore → lipolysis of sebum → free fatty acids irritate follicle wall

4. Immune response → follicle wall ruptures → contents spill into dermis → neutrophil recruitment → inflammatory lesion

Understanding these steps explains why each treatment class targets a different link in the chain:

5. How to Tell Acne Apart from Similar Conditions

Rosacea vs. Acne: The critical distinction Many patients — particularly women in their 30s–50s — self-treat rosacea with acne medications. Topical retinoids, which are a first-line acne treatment, can significantly worsen rosacea. A dermatology consultation is essential before committing to a topical regimen.

6. Diagnosis: What to Expect at the Clinic

Skin Examination We assess lesion count, type (comedones, papules, pustules, nodules), distribution, and severity using validated grading scales. Dermoscopy allows us to examine follicular structure and inflammatory depth.

Medical History

• Age of onset and progression

• Hormonal patterns (menstrual cycle correlation in women)

• All topical and oral treatments used previously

• Current skincare routine and products (ingredient list if available)

• Diet, sleep, stress level, occupation

• Medications that may contribute (corticosteroids, lithium, certain anticonvulsants)

Laboratory Tests (where indicated)

• Bacterial culture: if antibiotic resistance or folliculitis is suspected

• Hormonal panel (LH, FSH, testosterone, DHEA-S): if PCOS or androgen excess is suspected in women with treatment-resistant acne

Your First Visit — Step by Step

Book via LINE (24/7): https://line.me/R/ti/p/@744yxkjg
or call: +81-3-6456-4990
  ↓
Complete intake form (symptoms, history, products used)
  ↓
Consultation — approx. 25–35 minutes
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Diagnosis + treatment plan explained in plain English
  ↓
Prescription + skincare guidance / Payment (cash or credit card)

Bring: Insurance card, current medication list, and ideally the ingredient lists of your current skincare products.

7. Treatment Options — Topicals, Oral Medications, and Procedures

Topical Retinoids (Adapalene / Differin®) — Insurance covered Normalizes follicular keratinization; effective against comedones and mild inflammatory acne. Dryness and initial irritation are common — starting with every-other-day application and always pairing with a non-comedogenic moisturizer helps tolerance.

Benzoyl Peroxide (BPO / Bepio® gel) — Insurance covered since 2018 in Japan Bactericidal against C. acnes with no antibiotic resistance risk. Available as a single agent or in combination with adapalene (Epiduo® gel). A mainstay of modern acne therapy.

Combination BPO + Adapalene (Epiduo® gel) — Insurance covered Addresses both keratinization and bacterial proliferation in a single application. Convenient and highly effective for moderate acne.

Topical Antibiotics (clindamycin, nadifloxacin) — Insurance covered Always paired with BPO to prevent resistance development. Not recommended as monotherapy.

Oral Antibiotics (doxycycline, minocycline) — Insurance covered For moderate-to-severe inflammatory acne. Used for a defined course (typically 3 months) rather than indefinitely. Resistance surveillance is an important consideration.

Hormonal Therapy (low-dose OCP) — Self-pay for cosmetic indication For women with androgen-driven or menstrual-cycle-related acne. Reduces sebum production by suppressing androgen activity. Often discussed in conjunction with a gynecologist.

Isotretinoin (oral) — Self-pay in Japan The most powerful systemic acne treatment available — effective against all four pathological mechanisms. Reserved for severe nodulo-cystic acne or recalcitrant cases. Teratogenic — strict contraception required for women of childbearing age. We provide detailed counseling before and during treatment.

Procedures

• Comedone extraction: Clinical removal of blackheads and whiteheads using sterile tools — much safer than self-squeezing, which causes scarring

• Chemical peeling (glycolic acid, salicylic acid) — Self-pay: improves comedonal acne and post-inflammatory hyperpigmentation; promotes skin cell turnover

• Intralesional corticosteroid injection — Self-pay: rapidly deflates large painful nodules or cysts

Acne Scar Treatment

• Post-inflammatory hyperpigmentation (redness, darkening): topical tranexamic acid, vitamin C derivatives, chemical peeling, strict photoprotection

• Atrophic scarring (ice-pick, boxcar, rolling): fractional laser — we coordinate referral to specialist centers

8. How Long Does Treatment Take?

• Topical retinoids + BPO: 4–8 weeks to see initial improvement; full effect at 12–16 weeks

• Oral antibiotics: Meaningful improvement in 4–6 weeks for inflammatory lesions

• Hormonal therapy: Sebum reduction noticeable after 3–6 months

• Isotretinoin: Typically 4–6 months of treatment; high rate of long-term remission

Acne treatment requires consistency. Stopping treatment when the skin clears — without medical guidance — is the most common reason for relapse. Maintenance therapy and sustained skincare habits are the keys to long-term control.

9. Everyday Habits That Help

Skincare

• Wash face twice daily with a gentle, pH-balanced cleanser — not more

• Always moisturize, even with oily skin: choose non-comedogenic, oil-free formulas

• Apply broad-spectrum SPF 30+ sunscreen daily (non-comedogenic); UV exposure darkens post-inflammatory hyperpigmentation

• Check ingredient labels: avoid lanolin, mineral oil, and heavy silicones

Environment — Tokyo-specific Living and working in the Hiroo-Ebisu corridor means frequent exposure to urban pollution, which contributes to oxidative stress on the skin. A thorough (but gentle) cleansing routine after commuting is particularly important. If you walk along Hiroo Promenade or near Ebisu Garden Place on your way home, remove makeup and cleanse as soon as possible after arriving home.

Diet and lifestyle

• Reduce high-GI foods: white rice, bread, sugary drinks

• Limit dairy intake, particularly skim milk, which has higher insulin-stimulating properties

• Prioritize 7–8 hours of sleep — non-negotiable for skin repair

• Build stress outlets into your week: exercise, walks in Arisugawa-no-miya Memorial Park, or mindfulness practices

10. Risks of Leaving Acne Untreated — Scars and Psychological Impact

Post-inflammatory hyperpigmentation (PIH) Red or brown marks left after inflammatory acne. These are not technically scars — they can fade with treatment — but they often take months to years to resolve without intervention.

Atrophic (pitted) scars Ice-pick, boxcar, and rolling scars form when the dermis is permanently damaged by severe inflammatory acne. These are irreversible without procedural treatment (fractional laser, subcision, fillers). Prevention — by treating inflammatory acne before it destroys dermal collagen — is the only truly effective strategy.

Hypertrophic scars and keloids More common on the chest and back; particularly related to patient skin type and genetic predisposition.

Psychological impact Research consistently shows that acne severity correlates with rates of anxiety, depression, and social withdrawal. The burden is particularly high among young professionals in image-conscious work environments. These psychological dimensions are taken seriously in our consultations — not dismissed as vanity.

11. Who Is at Higher Risk?

• Adolescents (12–24): Hormonal surge during puberty; early treatment minimizes scarring

• Women aged 25–40 with adult acne: Menstrual fluctuations, cosmetics, and stress are common triggers

• Women with PCOS: Androgen excess drives treatment-resistant acne — hormonal assessment recommended

• People using topical or systemic steroids: Steroid acne is distinct from acne vulgaris — requires different management

• Expats in Tokyo: Transitioning to Japanese skincare products, diet, and environment can disrupt established skin routines; English-language dermatology care is available at our clinic

12. When to See a Doctor — Checklist

• ☑ OTC products have not improved your acne after 2 weeks

• ☑ You have painful, deep, or recurring nodules or cysts

• ☑ Acne scars (red marks, darkening, pitting) are appearing

• ☑ Acne extends to your chest or back

• ☑ Acne consistently worsens before your period

• ☑ You are over 25 and acne is new or worsening

• ☑ Acne is affecting your confidence, social life, or mental health

• ☑ The rash looks different from typical acne (strong itch, no comedones, sudden onset)

13. Prevention: Skincare, Diet, and Lifestyle

• Build a consistent, minimalist routine: Gentle cleanser → non-comedogenic moisturizer → SPF 30+ (morning). Add prescription actives as directed.

• Screen cosmetics before use: Look for "non-comedogenic" or "oil-free" labeling. Test new products on the jawline for a few days before full-face application.

• Check fragrance and preservative content in cosmetics purchased around Daikanyama or Platinum-dori — even prestige brands sometimes use comedogenic ingredients.

• Dietary moderation: Reduce high-GI foods and excess dairy; prioritize vegetables, lean protein, and whole grains.

• Sleep and stress: These are as important as any topical product. Acne is often a signal that the body's regulatory systems — hormonal and immunological — are under stress.

14. Dermatology Care at Yasashii Clinic Hiroo Shirokane

English-Friendly, Holistic Acne Care

We welcome patients from the international community in Hiroo, Minami-Azabu, Shirokane, and Ebisu. English consultations are available. We recognize that managing acne in a foreign country — with different product formulations, different prescription access, and potential language barriers — adds an extra layer of difficulty. We aim to remove that barrier entirely.

We accept Japanese national health insurance and self-pay. For international insurance plans, we provide documentation for reimbursement.

Dr. Suzuki's Approach

Dr. Suzuki's internal medicine and primary care background means that acne consultations at our clinic consider the full picture: hormonal status, medication interactions, dietary patterns, and psychological wellbeing — not just the surface of the skin. For women with suspected PCOS or androgen-driven acne, we coordinate with gynecology as needed.

"We treat the whole patient, not just the skin. Understanding why a specific person is breaking out in a specific pattern is the foundation of effective treatment."

For severe nodulo-cystic acne requiring laser treatment or for complex hormonal workup, we coordinate referrals to Tokyo Metropolitan Hiroo Hospital, Japanese Red Cross Medical Center, Kitasato University Kitasato Institute Hospital, and the University of Tokyo's Institute of Medical Science Hospital.

Access & Hours

• 5 min walk from Hiroo Station (Tokyo Metro Hibiya Line, Exit 2)

• 10 min walk from Ebisu Station (JR / Tokyo Metro)

• 13 min from Shirokanedai and Shirokane-Takanawa Stations

• Parking available

Opening Hours: Monday: 16:00–20:00 | Wednesday & Thursday: 10:00–14:00 / 16:00–20:00 Saturday & Sunday: 10:00–18:00 | Public Holidays: 10:00–14:00 Closed: Tuesday, Friday Please check the official website or call for the latest schedule.

Dermatology Services

About Us & Osur Physicians

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Contact Dermatitis

Book via LINE (24/7)

Phone +81-3-6456-4990

15. Summary

• Acne vulgaris is a multifactorial chronic skin condition driven by sebum overproduction, clogged pores, C. acnes proliferation, and inflammation — not poor hygiene

• Prescription treatments (topical retinoids, BPO, oral antibiotics, hormonal therapy, isotretinoin) are significantly more effective than OTC options for moderate-to-severe acne

• Acne scars are the most important reason not to delay treatment — inflammatory acne that is left untreated causes irreversible dermal damage

• Adult acne in women often requires a hormonal assessment alongside standard dermatological care

• A consistent, evidence-based skincare routine is as important as medication for long-term control

English FAQ

Q1. What causes acne? Acne results from four interacting processes: androgen-driven excess sebum production, abnormal follicular keratinization (clogged pores), proliferation of C. acnes bacteria, and the resulting inflammatory immune response. Hormones, stress, diet, and cosmetics can all exacerbate these processes.

Q2. Is acne contagious? No. Acne is not contagious. C. acnes is a normal skin commensal bacterium — it causes acne only when the follicular environment becomes favorable for its overgrowth, not through transmission between people.

Q3. How long does acne treatment take? Most topical treatments show meaningful improvement after 8–12 weeks. Hormonal therapies take 3–6 months. Isotretinoin typically produces sustained remission after a 4–6 month course. Acne management is a long-term commitment — stopping medication prematurely when the skin clears is a common reason for relapse.

Q4. Can OTC products clear my acne? For mild comedonal acne, OTC salicylic acid and sulfur-based products provide some benefit. For moderate-to-severe or inflammatory acne, prescription-strength treatments (adapalene, BPO — available only by prescription in Japan) are substantially more effective. If OTC products have not improved your skin within 2 weeks, a dermatology consultation is advisable.

Q5. When should I see a dermatologist? If OTC treatments have not helped after 2 weeks; if you have painful, deep nodules or cysts; if scars are appearing; if acne is affecting your confidence or daily life; or if adult acne is new or worsening after age 25.

Q6. Does diet affect acne? Evidence supports an association between high-glycemic-index diets, excess dairy consumption, and acne worsening. Reducing white rice, bread, sugary drinks, and skim milk while increasing vegetables and whole foods may help. Diet alone is unlikely to clear moderate-to-severe acne — it should complement, not replace, medical treatment.

Q7. Are there treatments for acne scars? Yes. Post-inflammatory hyperpigmentation (red or brown marks) responds to topical treatments (tranexamic acid, vitamin C), chemical peeling, and strict photoprotection. Atrophic (pitted) scarring requires procedural treatment — fractional laser, subcision, or fillers — which we can arrange through referral.

Q8. Do you see foreign patients? Is English available? Yes — we regularly treat acne in expats and foreign residents living in Hiroo, Minami-Azabu, Shirokane, and Ebisu. English is available at our clinic. Book online at https://line.me/R/ti/p/@744yxkjg or call +81-3-6456-4990.

Q9. Is acne treatment covered by Japanese health insurance? Standard dermatology consultations, topical prescriptions (adapalene, BPO, combination agents, topical antibiotics), and oral antibiotics are covered by Japanese health insurance. Chemical peeling, isotretinoin, and hormonal therapy (when used purely for acne without a gynecological indication) are self-pay.

Q10. Can I have an online consultation for acne? Follow-up consultations and prescription renewals are available online. For first visits — particularly if you need a physical examination to distinguish acne from rosacea, folliculitis, or another condition — an in-person visit is recommended.