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Acne          Images                   -  see also KP Derm - Acne

Acne lesions

  1. Noninflammatory lesions: open and closed comedones.
  2. Inflammatory acne lesions: papules, pustules, and nodules (cysts).
    Papules are less than 5 mm in diameter.
    Pustules have a visible central core of purulent material.
    Nodules are greater than 5 mm in diameter. Nodules may become suppurative or hemorrhagic. Suppurative nodular lesions have been referred to as cysts because of their resemblance to inflamed epidermal cysts.
    Disfiguring scars.

Classification & Grading of Inflammed Acne

  1. Mild Acne:  Papules/pustules +/++ (few to several); nodule 0
  2. Moderate Acne:  Papules/pustules ++/+++ (several to many); nodule +/++ (few to several)
  3. Severe Acne:  Papules/pustules +++/++++ (numerous to extensive); nodule ++/+++ (several to many)

Therapeutic Agents:

  1. Antibacterial effect:
    Benzoyl peroxide cleanser, topical antibiotics as Cleosin-T, oral antibiotics as tetracycline 250-500 mg bid, Isotretinoin (works indirectly)
  2. Anti-inflammatory effect:
    intralesional corticosteroids, oral corticosteroids, NSAID, antibiotics (prevent neutrophile chemotaxis)
  3. Normalize the pattern of follicular keratinization:  
    tretinoin, isotretinoin (Accutane)
    Retinoids include Tretinoin (Avita® 0.025% or Retin A® Cream) and Adapalene (Differin® Gel).
  4. Inhibit sebaceous gland function:
    estrogen, oral corticosteroids at very low dose as Prednisone 5 - 7.5 mg), isotretinoin (Accutane), anti-androgens as spironolactone


  1. Wash face twice a day with mild cleanser.

  2. Use only non-comedogenic products on the face. Use moisturizer with sunblock.

  3. Antimicrobials kill the bacteria. Common antimicrobials include benzoyl peroxide and topical antibiotics.

  4. Retinoids help to open the pores. Retinoids include Tretinoin (Avita® 0.025% or Retin A® Cream) and Adapalene (Differin® Gel).

Mild acne: (Primarily blackheads):

Excellent topical therapy combines
Topical retinoids (Vit. A acid) e.g. Tretinoin (Avita® 0.025% gel 15, 45 gm or 0.025%- 0.05% cream 20, 45 gm, Retin A® 0.05% liquid 28 mL) or Adapalene (Differin® 0.1% gel 45 gm QHS and over-the-counter benzoyl peroxide 5% QAM.
[Note: Benzoyl peroxide may bleach clothing. If too irritating, try Sulfur and Sodium Sulfacetamide (Novacet®, Sulfacet®), or Clindamycin (Cleocin T®) topical solution.
Give any topical therapy at least 6 weeks to assess effectiveness. For mild acne, topical therapy over 6 weeks is usually very effective. The patient must apply topical medications all over.
For acne on chest, shoulders, and back: Apply benzoyl peroxide 10% QHS. No spot treating.

Moderate Acne: (Papules, pustules, or unresponsive to the above treatment)

If the acne is not responsive or there is moderate, inflammatory facial acne, add Tetracycline 500 mg BID or Doxycycline (Vibramycin®) 100 mg BID. Caution patient about sun exposure. Give any regimen 6 weeks. If the acne fails to respond, refer to Dermatology.

Severe acne: (Numerous cysts, scarring, or unresponsive to the above treatment)

If scarring is occurring, therapy must be aggressive.

Refer directly to Dermatology. Oral retinoid therapy, e.g. Isotretinoin (Accutane®), is often recommended for treatment of severe recalcitrant acne.

During pregnancy: Therapy is limited to topical benzoyl peroxide and erythromycin. In unusually severe cases, consult with OB/GYN to consider oral erythromycin.


Acne Keloidalis  

Rx: (Dr. S.Y.)

Low-Dose 20 mg bid x 6 months Doxycycline for Moderate Acne

The usual dose of oral doxycycline for treating acne is 50 mg or 100 mg, twice daily. This agent presumably works by decreasing the population of the skin bacterium, Propionibacterium acnes, which is thought to be an important element in the pathogenesis of acne. Previous research has suggested other potential actions of doxycycline, however, including down-regulation of inflammatory mediators and inhibition of P. acnes-derived lipase, with a resultant reduction in follicular free fatty acid levels. These effects can occur at doses of doxycycline that are too low to inhibit bacterial growth. In this manufacturer-sponsored, multicenter, double-blind, randomized study, investigators examined the effect on moderate facial acne of a 6-month course of 20-mg doxycycline twice daily versus placebo.

Among the 40 patients completing the study, mean reduction in inflammatory lesions and comedones was 52% in the doxycycline group versus 18% in the placebo recipients, a significant difference. Doxycycline produced no change in the composition of the surface skin flora or its antimicrobial susceptibility.

Comment: Whether doxycycline improved acne in these patients by an antimicrobial effect on organisms in the follicles or by another action is unclear, but this low-dose regimen appears to treat acne effectively without altering the antimicrobial susceptibility of the skin flora. Furthermore, previous trials of low-dose doxycycline have demonstrated no change in the antibiotic sensitivity of bacteria in the gastrointestinal and genitourinary tracts. Low-dose doxycycline might be the safest approach to using antibiotics for treating acne (Journal Watch Dermatology Jun 14 2003).— Jan V. Hirschmann, MD, Puget Sound VA Medical Center, and University of Washington School of Medicine, Seattle.   Published in Journal Watch May 20, 2003

Skidmore R et al. Effects of subantimicrobial-dose doxycycline in the treatment of moderate acne. Arch Dermatol 2003 Apr; 139:459-64.

[Original article]  [Medline abstract]  [Download citation]

Acne             REF:  BestDx/BestRx 2004 ACP

Mark Lebwohl, M.D.
Mt. Sinai School of Medicine

Definition/Key Clinical Features

* Characteristic skin lesions

* Most commonly affects face but can involve back and chest

* Earlier onset and increased severity in males

* Premenstrual flares common in females

Major forms

Comedonal Acne

Inflammatory Acne

Clinical Variants

Differential Diagnosis

Best Tests:   * Diagnose by clinical features

Best Therapy: * Depends on acne type and severity

Topical Therapies

Comedonal Acne

Inflammatory Acne

* Treatment alternatives (by effectiveness)

Topical Drugs for Acne


Benzoyl Peroxide


* Clindamycin

* Erythromycin

* Erythromycin–benzoyl peroxide

* Sodium sulfacetamide-sulfur

Azelaic Acid

Sulfur and Resorcinol

Salicylic Acid

Systemic Therapies for Nodulocystic Acne or Inflammatory Acne Unresponsive to Topical Therapy

Antibiotics: First-line Therapy

* Doxycycline

* Erythromycin

* Minocycline

* Isotretinoin

* Tetracycline

* Trimethoprim-sulfamethoxazole

* Norgestimate-ethinyl estradiol

Other Therapies

* Consider referral for the following:

Best References

July 2004