Microcysts: Causes, Prevention, and Treatments

What is a microcyst, and how does it form?

Microcysts (closed comedones) are small, white or flesh-colored lesions that are firm and raised, typically measuring 1 to 3 mm, and located beneath a thin layer of intact skin. They result from pilosebaceous follicles blocked by a buildup of sebum and keratinized cells (keratin). Unlike blackheads (open comedones, oxidized by air), microcysts remain closed at the surface, which gives them their pearly white appearance. They are one of the basic lesions ofacne and can progress to inflammatory lesions (papules, pustules) or remain non-inflammatory over the long term.

What factors contribute to the development of microcysts?

Several factors contribute to their development:

• Excess sebum under the influence of androgens.
• Hyperkeratinization of the hair follicle canal, which blocks the pore.
• Hormonal fluctuations: puberty, menstrual cycle, pregnancy, postpartum, menopause, polycystic ovary syndrome (PCOS).
• Comedogenic cosmetics and hair care products (heavy mineral oils, certain highly comedogenic plant oils, occlusive silicones, thick waxes).
• Repeated friction (acne mechanica) caused by helmets, straps, or masks worn for extended periods.
• Stress, insufficient sleep, and a high-glycemic-index diet (effect varies depending on individual profiles).
• Certain medications (corticosteroids, lithium, anabolic steroids).

How can you prevent microcysts from forming?

A tailored skincare routine and a few simple habits can help limit aggravating factors:

• Gently cleanse morning and night with a product suitable for combination to oily skin (syndet, a mild gel with a pH close to 5.5).
• Light moisturizer, such as a non-comedogenic gel or fluid.
• Targeted treatments with niacinamide (B3) orsalicylic acid at cosmetic concentrations (max 2% according to EC Regulation 1223/2009), to be gradually increased based on tolerance.
• Non-comedogenic cosmetics and foundations; always remove makeup in the evening.
• Replace pillowcases, makeup brushes, and sponges regularly.
• Do not touch or squeeze the lesions.
• Use a non-comedogenic, lightweight sunscreen.
• Eat a varied diet, get enough sleep, and manage stress.

What treatment options are available for microcysts?

Treatment depends on the extent and progression of the condition:

• Topical cosmetic treatments: salicylic acid (BHA, max 2% in cosmetics per Regulation (EC) No. 1223/2009; photosensitizing: SPF required), niacinamide, low-concentration alpha-hydroxy acids. Well tolerated with long-term routine use.
• Prescription topical retinoids (adapalene, tretinoin, topical isotretinoin): the standard of care for closed comedones. Photosensitizing agents; apply in the evening with SPF in the morning; some are contraindicated during pregnancy. Distinguish these from over-the-counter cosmetic retinol, which is less potent and can be used alongside—but not as a substitute for—medical treatment.
• Benzoyl peroxide gel or cream (typically 2.5% to 5%): available at pharmacies by recommendation or with a prescription. Precautions: photosensitizing; bleaches fabrics and bedding; may cause initial irritation.
• Professional extraction at a dermatologist’s office or medical spa: a precise procedure using a fine needle and controlled expression, performed under strict hygienic conditions. This is preferable to self-extraction.
• Superficial chemical peels with glycolic or salicylic acid performed in a clinic, for targeted skin renewal.
• Microdermabrasion or gentle mechanical exfoliation in a clinic, as indicated.
• Prescriptionoral medications for widespread or resistant cases: cyclines (doxycycline, lymecycline), hormonal therapy for women in certain situations, oral isotretinoin for severe forms (teratogenic; ANSM pregnancy prevention program; strict medical monitoring).

When should you see a dermatologist for microcysts?

A dermatology consultation is recommended if:

• The microcysts persist or increase in number despite a properly followed skincare routine for 1 to 3 months.
• Inflammatory lesions (papules, pustules, nodules) appear.
• Signs of infection (redness, warmth, pain, pus).
• Psychological, social, or professional impact.
• Scarring develops.
• Acne in adult women with signs of hyperandrogenism (irregular periods, hirsutism, alopecia): rule out PCOS or another endocrine disorder.
• Acne that persists beyond the usual age range or that begins late in life.
• Current pregnancy or plans to become pregnant (treatment adjustments).

How can a microcyst be distinguished from other types of pimples?

Several lesions may resemble a microcyst:

• Microcyst (closed comedone): firm, raised, non-inflammatory, painless, with no visible opening.
• Blackhead (open comedone): visible opening with brown-to-black oxidized contents.
• Papule: red, inflamed pimple with no visible pus.
• Pustule: a papule with a central, yellowish, pus-filled center.
• Nodule, cyst: larger, deeper, painful.
• Milia: small, very superficial white cysts (often around the eyes), distinct from acneic microcysts in terms of their location and mechanism.
• Epidermoid cysts: larger, palpable lesions, sometimes infected.
• Sebaceous gland hyperplasia: small, slightly yellowish, umbilicated lesions, common after age 30.

A dermatological examination allows for an accurate diagnosis and guides appropriate treatment.

Are there any natural remedies for microcysts?

For very mild cases, a few approaches can complement an appropriate skincare routine:

• Tea tree essential oil diluted to a maximum of 1% in a carrier oil, applied sparingly. Test on the inner elbow for 24 to 48 hours. Standard precautions: pregnancy, breastfeeding, children under 7 years of age, potential for sensitization.
• Niacinamide serum (B3): regulates sebum and visibly minimizes the appearance of pores.
• Green or white clay as an occasional mask (10 to 15 minutes); rinse off before it dries completely to avoid irritation.
• Honey as an occasional mask: traditionally known for its soothing effects, provided there is good individual tolerance. Clinical data on acne remains limited.

Avoid: undiluted apple cider vinegar (highly acidic acetic acid, irritating), undiluted lemon (photosensitization due to furocoumarins), toothpaste, or baking soda applied topically (online remedies with no proven efficacy, carrying a risk of irritation and compromised skin barrier).

Can microcysts be squeezed at home?

Self-extraction is strongly discouraged for several reasons:

• Risk of secondary infection (folliculitis, abscess) in the absence of strict aseptic conditions.
• Risk of permanent scarring (atrophic, hypertrophic, and marked post-inflammatory hyperpigmentation in skin types IV through VI).
• Risk of aggravating local inflammation and delaying resolution.
• Technical difficulty: A closed microcyst has no visible opening, and its extraction requires a precise maneuver using a fine instrument.

Professional extraction in a dermatology office or at a trained medical facility, under aseptic conditions and with the appropriate tools, is the preferred option. At home, it is best to use topical treatments (salicylic acid, cosmetic retinol, or prescription topical retinoids) that take effect within a few weeks to a few months.

What impact does diet have on microcysts?

The link between diet and acne (including microcysts) has been the subject of several studies with consistent findings:

• A high-glycemic-index diet (added sugars, sodas, pastries, ultra-processed foods) can worsen acne in some people (due to its effect on insulin levels and IGF-1).
• Dairy products (especially skim milk) have been linked to a potential worsening of acne in several studies.
• A diet rich in fruits, vegetables, nuts, and fatty fish (omega-3) has an overall beneficial effect on systemic inflammation.
• Zinc contributes to skin health; supplementation may be considered in cases of deficiency.

The effect varies depending on individual profiles. An individualized approach with a doctor or dietitian-nutritionist is preferable to empirical elimination.

What foods should be avoided in cases of microcysts?

For an appropriate skincare routine, several ingredients or product categories should be limited:

• Heavy mineral oils, paraffin, and certain highly comedogenic vegetable oils (unfractionated coconut oil, cocoa butter).
• Occlusive silicones applied in repeated thick layers.
• Thick waxes, lanolin.
• Foundation and BB creams applied in thick layers without proper makeup removal.
• Oily hair products (oils, hair balms) that drip onto the forehead and temples.
• Harsh mechanical scrubs and rotating brushes that can irritate acne-prone areas.
• Over-exfoliating routines (simultaneous use of acids and retinoids) that can damage the skin barrier.

Opt for non-comedogenic products with lightweight textures that have been dermatologically tested, and tailor your routine to your personal tolerance. Test any new product on the inner elbow for 24 to 48 hours before regular use.

Sources: HAS—acne recommendations; ANSM—proper use of isotretinoin, benzoyl peroxide, and retinoids; Inserm—acne report; French Society of Dermatology (SFD).