Acne
Types, causes, triggers, and what actually moves the needle.
Overview
Acne is a chronic, inflammatory skin condition affecting people across ages and demographics. It’s commonly driven by clogging and inflammation of the pilosebaceous unit (hair follicle + sebaceous gland), with contributions from excess sebum, abnormal shedding of skin cells, inflammation, and microbial shifts (often involving Cutibacterium acnes).
What it’s not
- Not “dirty skin”: it’s follicle biology + immune signaling.
- Not “one product fixes all”: severity + lesion type dictate strategy.
Types of Acne
Comedonal Acne
- Open comedones (blackheads): oxidized keratin/sebum
- Closed comedones (whiteheads): trapped under the skin
- Driver: excess sebum + hyperkeratinization
Inflammatory Acne
- Papules: red, raised lesions
- Pustules: papules with visible pus
- Driver: immune response + inflammation around clogged follicles
Nodulocystic Acne
- Nodules: deep, painful, solid lesions
- Cysts: deeper lesions that may be fluid/pus-filled
- Risk: scarring; often needs systemic treatment
Acne Conglobata
- Severe nodulocystic acne with interconnected lesions and scarring
- Often requires systemic therapy
Acne Fulminans
- Acute severe acne with systemic symptoms (fever, myalgias, arthralgias)
- Medical urgency: requires clinician-managed treatment
Why Acne Happens
1) Excess Sebum
- Often androgen-driven
- Oily environment increases clogging risk
2) Follicular Hyperkeratinization
- Dead skin doesn’t shed normally
- Build-up combines with sebum and blocks pores
3) Microbial Shifts
- C. acnes can amplify inflammation
- Acne is not “dirty skin” — it’s immune + follicle biology
4) Hormones
- Puberty, menstrual cycle shifts, PCOS, pregnancy
- Hormonal acne often clusters along jawline/chin
5) Diet (for some people)
- High glycemic load → insulin/IGF signaling can worsen acne
- Dairy is a frequent individual trigger, especially skim
6) Stress
- Cortisol and inflammatory signaling can intensify flares
7) Occlusion & Products
- Comedogenic products (“acne cosmetica”)
- Friction + heat + moisture (“acne mechanica”)
8) Medications
- Examples: steroids, lithium, some anticonvulsants
Clinical Notes
- Severity is usually graded mild → moderate → severe based on lesion type and depth.
- Hormonal workup is commonly considered in adult-onset acne with irregular menses, hirsutism, or rapid onset.
- Scarring risk increases with nodules/cysts and delayed control.
- Early control is basically “pay now or pay later” for scarring.
Quick Map
| Type | Features | Common Approach |
|---|---|---|
| Comedonal | Blackheads/whiteheads | Retinoid base + gentle routine |
| Inflammatory | Papules/pustules | Anti-inflammatory + antimicrobial strategy |
| Nodulocystic | Deep painful lesions | Often needs clinician-managed systemic therapy |
Next Steps
Want to add a treatment ladder (OTC → Rx → systemic), a trigger tracker, or a routine builder that outputs a personalized AM/PM plan?