Acne - Guidelines for Prescribing Topical Treatment

  • Acne vulgaris (acne) is the formation of comedones, papules, pustules, nodules, and/or cysts as a result of obstruction and inflammation of pilosebaceous units (hair follicles and their accompanying sebaceous gland).

  • It typically starts at puberty, increases in severity until the late teens then slowly abates. However, later onset during adult years can occur - 5 % of women, 1 % of men.

  •  Diagnosis is based on physical signs and symptoms. Further investigation is not necessary unless secondary causes are suspected.

  • Treatment is a variety of topical and systemic agents intended to reduce sebum production, infection, inflammation and to normalize keratinization.

  • For more information and photos, see

Signs and Symptoms
  • Typically affects face, neck, chest, upper back, and upper arms.

  • Presence of comedones. 

    • Closed comedones are called whiteheads.  Whiteheads are flesh-colored or whitish raised bumps 1 to 3 mm in diameter.

    • Blackheads are open comedones with a dark center (oxidized keratin, dead cells).

    • Comedones are not infected.

  • Presence of inflammatory lesions such as:
  • Papules (small red, round or oval raised bumps)

  • Pustules (papules containing pus)

  • Nodules (tender, red swellings with undefined borders)

  • Cysts (deep pustules)

  • You will also want to assess the severity of the patient’s acne:
    • Mild:           Some papules or pustules; no nodules or cysts
    • Moderate:   Many papules and pustules; few nodules, no cysts
    • Severe:       Numerous papules and pustules; many nodules or cysts
Differential Assessments

Rule out the following conditions which have signs / symptoms that may resemble acne vulgaris:

  • First, distinguish acne vulgaris from other types of acne based on location and type of lesions:
  • Acne Variant





















    Cysts, abscesses, sinus tracts







    Ulcerating cysts









    pomade use






    Occurs near hair-line 








    Occurs where cosmetics used















    Crusts, scar, erosions, hyperpigmentation








    • Acne conglobata occurs when sinus tracts (channels) form between acne lesions resulting in the formation of cysts and abscesses.  This type of acne  is considered severe and often requires systemic treatment. Suspected cases should be referred to their physician.

    • Acne fulminans is an acute eruption of large inflammatory nodules, occurring most frequent in males.  It also presents with arthralgia and fever.  This is a serious condition and requires emergency treatment.

    • Contact acne may be caused by pomade use, certain cosmetics, or occupational exposure to oil. 
      • Suspect pomade or hair product use if the acne occurs near the hairline.
      • Ask about the use of oil-based cosmetics and if make-up is removed each night. 
      • Exposure to oily substances in the environment, such as working as a fast-food cook, should also be investigated. 

    • Excoriated acne results from the patient picking or scratching at their lesions.  A hallmark sign of this are scars in the absence of cysts or nodules, or hyperpigmentation of an area that can last years.

    • Mechanical acne is the result of physical irritation to an area leading to the acne lesions, such as a sweat band rubbing against the forehead.

  • Drug-induced acne.  Medications that can cause/worsen acne:  glucocorticoids (oral, inhaled, and topical), androgens, oral contraceptives containing progestins with more potent androgenic actiivity (norethindrone, levonorgestrel, norgesterl), phenytoin, lithium, isoniazid, and others. Has the patient recently started a new medication preceding the acne flare up? 
  • Rosacea - acne-like lesions without comedones, associated with facial flushing, telangiectases, and dry eyes.

  • Milia - small white cysts just under the surface of the skin. Typically seen in infants but can occur in all ages. Harmless, no treatment necessary unless very bothersome to the patient.

  • Perioral dermatitis - lesions clustered around mouth and nasal folds. More common in women than men. Most frequently caused by topical steroid use.

  • Skin infections such as impetigo (small fragile pustules; honey-coloured crusted erosions) or folliculitis (red, often itchy, papules and/or pustules, occur at base of a hair shaft).

When to Refer

Diagnosis of acne is based on the presence of comedones and / or inflammatory lesions. Patients with mild acne signs / symptoms generally do not require further investigation, however assessment by the patient's primary care provider is recommended in the following situations:

  • Pregnancy.

  • Age < 12 years - possible hormonal issues

  • Onset at age >30 - possible rosacea
  • Widespread distribution of lesions beyond face making topical therapy impractical.  Refer to patient's primary care provider as a systemic antibiotic may be warranted.

  • Number and severity of lesions indicates moderate or possibly severe acne:

    • Number of comedones > 20, OR
    • Number of inflammatory lesions (papules, pustules, nodules, or cysts) > 15, OR
    • Total number of lesions > 30 total lesions

  • Family history of scarring acne.

  • Signs of hyperandrogenism are present such as:  hirsutism, infertility, infrequent menses, insulin-resistant diabetes, middle-age onset in women.

  • Sudden onset of acne associated with fever and arthralgias - possibly acne fulminans. Treatment for acne fulminans involves oral steroids and isotretinoin.

  • Onset at age > 30 years. Possible rosacea.

  • Excessive embarrassment, anxiety, low self-esteem, or feelings of shame.

  • Unable to confirm patient's self-diagnosis of acne. Patient's condition requires further investigation and /or physician-supervised therapy.
Non-pharmacological treatment
  • General measures and basic care are recommended at all levels of management.

  • Affected areas should be cleansed twice daily. More frequent washings, use of antibacterial soaps, and scrubbing confer no added benefit.  Scrubbing may promote the development of inflammatory lesions.

  • Changes in diet are unnecessary and ineffective, although moderation of milk intake might be considered for treatment-resistant adolescent acne.

  • Picking, squeezing or excoriation of inflammatory lesions delays healing and promotes scarring, and therefore should be avoided.

  • Choose cosmetics, hair products, creams or lotions which are labelled "oil-free" ,"water-based" or "non-comedogenic".

  • Minimize mechanical occlusion from turtlenecks, bra straps, shoulder pads, orthopedic casts, and sports helmets.

  • Reduce stress level.  Studies have shown some correlation between stress level and acne severity among high school and university students.

  • Various lasers, intense pulsed light, microdermabrasion, chemical peels and photodynamic therapy are all helpful in certain situations but are expensive, rarely insured, often painful and must be administered on an ongoing basis.  They are rarely required for effective acne management.

Over-the-counter drug options:

  • Topicals should be applied to the entire affected area and not used as spot treatment.

  • Sulfur, salicylic acid, and resorcinol:  these are peeling agents and are of minor therapeutic value.

  • Benzoyl peroxide 2.5%-10%. (prescription required for > 5% strengths)

    • Mildly comedolytic and antibacterial. 

    • First line therapy for mild to moderate acne.

    • 5% formulations as effective as 10% prescription formulations with less skin irritation.

    • Water-based formulations are less drying than alcohol-based products.

    • Directions:

      • Apply to entire affected area once daily at bedtime or twice daily

      • Start with lower strength (2.5%-5%) or less frequent nighttime application (i.e. every other night)

      • Increase strength or frequency as tolerated

      • Benzoyl peroxide degrades retinoids and antibiotics - administration times must be separated or a combination product used

    • Allow 3 months for improvement.

    • Follow-up with patient to assess effectiveness at 8 weeks.

    • Patient may see initial worsening for the first 2 to 4 weeks.

    • May cause bleaching of hair, clothing, towels, and bedding.

Prescription drug options for acne

1. Topical Retinoids (level 1 [likely reliable] evidence)

  • Some guidelines recommend topical retinoids as first line treatment for mild to moderate comedonal (IE. Non-inflammatory lesions predominate) acne.

  • There are three choices: Tretinoin, adapalene and tazarotene.

    • Tretinoin is the most cost effective but also the most photosensitizing.

    • Adapalene is the least irritating, but most expensive. A commercial product containing adapalene and benzoyl peroxide is also available.

    • Tazarotene is the most potent, and therefore the most likely to cause irritation.

      Tretinoin is the most cost effective but also the most photosensitizing. 

  • The retinoids come in cream and gel formulations.  Creams are typically less irritating, but less potent than gels.

  • Start with the lowest concentration available or the chosen product, and increase as needed.
  • Directions

    • Apply to entire affected area, at bedtime waiting 15 - 30 minutes after washing to ensure that skin is dry. (Moist skin is more absorbent. This increases the risk of skin irritation.)

    • One to two finger-tip units is enough to cover the entire face. Product should disappear almost immediately; if some product remains unabsorbed, decrease the amount applied.

    • Start with a low concentration product and apply only once every 2 to 3 nights.

  • Initial worsening may occur in the first 2 to 4 weeks of treatment; up to 12 weeks to see maximum improvement. 

  • Skin redness and irritation is the most common side effects.  Slowly titrating up application time can reduce this.

  • Follow-up with patient to assess response to therapy at 8 weeks.

  • After successful course, MD may consider step-down to less frequent (once every 2-3 nights) maintenance treatment.

  • Recommend that the patient also use sunscreen SPF 15-30 due to risk of photosensitization (lower risk with adapalene).

2. Topical Antibiotics (level 1 [likely reliable] evidence)

  • Most effective for inflammatory acne
  • Clindamycin and erythromycin are the most useful antibiotics for topical acne treatment.

  • Use in combination with benzoyl peroxide reduces the chance of bacterial resistance developing. 

  • Topical antibiotics are most effective for inflammatory acne (i.e. papules, pustules, nodules, and cysts).

  • Less irritating than benzoyl peroxide and tretinoin but may still cause some redness, peeling, itching, dryness and burning

  • Recommend using fragrance-free moisturizer for dryness.

  • Directions:

    • Apply to entire affected area twice daily.

  • 8 to 12 weeks for skin improvement. 

  • Follow-up with patient to assess effectiveness at 8 weeks.

  • Treatment can be stopped when inflammation is gone.

3. Topical Antibiotics and Benzoyl Peroxide  

  • Best for cases of moderate acne or those with mixed lesion types.
  • Use of combination prevents development of antibiotic resistance.

  • Similar or increased effectiveness vs. topical antibiotics alone.

  • Directions:

    • Apply once daily at bedtime to entire affected area

    • Dosage may be increased to twice daily use

  • Allow 2 to 4 weeks for noted improvement; allow 8 to 10 weeks for optimal results.

  • Follow-up with patient to assess effectiveness at 8 weeks.

  • Recommend using fragrance-free moisturizer for dryness.

4. Combination Topical Antibiotics and Retinoid

  • Best for cases of moderate acne or those with mixed lesion types.

  • Combining topical antibiotics with topical retinoids is also effective against mild acne and may improve treatment outcome.

  • Combinations available:
    • adapalene + benzoyl peroxide
    • tretinoin + clindamycin
    • tretinoin + erythromycin

5. Azelaic Acid

  • Available as 15% gel (Finacea®)
  • Antibacterial, anti-inflammatory and exfoliant effect; effective for comedonal and inflammatory acne
  • Similar to benzoyl peroxide in efficacy, but may cause less irritation in some patients.  May also be less irritating than retinoids. Consider as an alternative to benzyl peroxide or retinoids if they are not tolerated.
  • May have additional benefit for post-inflammatory pigmentation
  • Applied twice daily
  • Initial worsening in 2-4 weeks; maximum improvement in 16 weeks

6.  Choices during pregnancy and lactation 

  • Topical use of BP, erythromycin and clindamycin are considered safe due to minimal systemic absorption.  These are also compatible with breastfeeding

  • Retinoids are contraindicated during pregnancy

  • Retinoids can be used during lactation, but little data is available, so prefer using an alternative if possible.
General Advice / Monitoring
  • General measures and basic care (under non-pharmacological treatment) should be recommended at all levels of management.

  • Topicals should be applied to the entire affected area and not used as "spot treatment".

  • Symptoms may worsen initially for the first 2 to 4 weeks; may take up to 3 months for maximum improvement of symptoms.

  • Tolerance to the irritation caused by topical usually occurs with continued use but patients should be advised to consult their pharmacist or patient's primary care provider if the skin irritation becomes severe.

  • Recommend a method to titrate up contact time to help build tolerance and reduce irritation

Assess Benefit

  • Follow-up with patient to assess effectiveness at 8 weeks

  • A reasonable goal for 8 week progress would be:

    • Lesion count decreased by 10-25%

    • Comedones have decreased or less are developing

    • Inflammatory lesions have mostly resolved in a few weeks

  • If no response or symptoms worsening, refer to patient's primary care provider.

  • If inadequate response, consider switching topical agents (e.g.a retinoid to replace BP) or combining retinoid and BP. For inflammatory symptoms (i.e. papules, pustules), consider adding a topical antibiotic.

  • If the patient's symptoms are responding well to initial agent(s), contact patient's primary care provider for refills. For patients who have responded well, benzoyl peroxide and topical retinoids can be continued indefinitely on a maintenance regimen.
  • Topical antibiotics should be discontinued after resolution of inflammatory symptoms.

Assess for Adverse Effects

  • For skin dryness, recommend a frangrance-free, water-based moisturizing cream.

  • Excessive skin irritation with benzoyl peroxide:

    • Try a lower strength of benzoyl peroxide and or a different base formulation (e.g. a cream for its moisturizing effect) and / or less frequent application, e.g., every other day.

    • Drying effects - Lotion < water-based gel < alcohol-based gel.

    • Contact dermatitis is a rare adverse effect. If suspected, patients should discontinue benzoyl peroxide therapy and consult their primary care provider.

  • Excessive skin irritation with retinoids:
    • Start with lower strength and gradually increase dose.

    • Apply on alternate days initially, then increase to once daily as tolerance develops.

    • Consider switching to adapalene if not initial agent.

    • If very irritating, the product can be washed off after 15 - 20 minutes.

  • Topical antibiotics rarely cause excessive skin irritation.

  • If hypersensitivity reaction to any product, discontinue and consider switching to a different product once reaction has resolved or refer patient to primary care provider.
Acne Products

Detailed information on contraindications, cautions, adverse effects and interactions is available in individual drug monographs in the CPS (e-CPS), Lexi-Comp, AHFS, or other reliable drug monograph references. For comprehensive drug comparisons, see RxFiles charts (
This information should be routinely consulted before prescribing.

Generic Name


0.01% TOPICAL CREAM        

0.05% TOPICAL CREAM        

0.025% TOPICAL CREAM      

0.01% TOPICAL GEL              

0.05% TOPICAL GEL              


0.04% GEL (microsphere)


Tretinoin + Sunscreens





Tretinoin :  Clindamycin

0.025% :  1.2% TOPICAL GEL


Tretinoin :  Erythromycin

0.05%  :  4% TOPICAL GEL

0.025% : 4% TOPICAL GEL

0.01%  :  4% TOPICAL GEL


Benzoyl Peroxide




10% WASH



Clindamycin : Benzoyl Peroxide









Erythromycin : Benzoyl Peroxide









Adapalene + Benzoyl Peroxide

0.1%/2.5% TOPICAL GEL





Azelaic Acid


Prescribing and Billing Details
  • pseudoDIN: 00951087
    • May bill 4 claims per 365 days per patient

  • May prescribe sufficient quantity for 8 weeks of treatment with one product.  May choose to prescribe 4 weeks of treatment with one refill instead.
    • If satisfactory response after the 8 week follow-up, refer to patient's primary care provider for further refills
    • If unsatisfactory response, may give another 8 week trial of a different medication (max of two trials per patient)

  • Only products with an official indication from Health Canada for acne and/or recommended by reputable and reliable guidelines are considered for these guidelines. Only the active ingredients in the "products" section are approved for pharmacist prescribing.
Treatment Flowchart
Pharmacist Assessment Documents
References / Suggested Reading
  1. e-therapeutics+ - Acne. Available at SHIRP (Free access, registration required)
  2. Emedicine - Acne Vulgaris . (Free access, registration required).
  3. Merck Manual Professional:  Acne Vulgaris (Free access)
  4. RxFiles. Acne Pharmacotherapy Comparison Chart. Available at
  5. Uptodate: Pathogenesis, clinical manifestations, and diagnosis of acne vulgaris. (Subscription required)
  6. Dynamed - Acne (Subscription required).

Prepared by medSask.
Reviewed by Dr. L. Sandomirsky, Family Physician, Loren Regier, Pharmacist, RxFiles Academic Detailing Program,
Dr. J. Taylor, Professor, College of Pharmacy and Nutrition
Funded by the Saskatchewan College of Pharmacy Professionals.
Posted May 2010, Updated October 2018.