Azelaic acid is a topical anti-acne agent. Azelaic acid is a naturally occurring dietary constituent (whole grain and animal products) and can be formed endogenously from longer-chain dicarboxylic acids, metabolism of oleic acid, and omega-oxidation of monocarboxylic acids. Azelaic acid is used as a treatment for acne vulgaris and is one of the leading treatments for this condition in Europe where it has been marketed as a 20% cream since 1989 by Schering. The drug is also effective for reducing the number of inflammatory pustules and papules associated with rosacea. Reduction in erythema may occur; however, efficacy has not been established for erythema associated with rosacea without papules and pustules. Azelaic acid has been administered orally and intravenously; however, only a topical formulation is marketed in the United States. The drug was originally FDA approved as a 20% cream for the treatment of acne vulgaris in September 1995; several brand name creams are now available. A 15% topical gel and foam were FDA-approved for the treatment of rosacea in December 2002 and July 2015, respectively.
General Administration Information
For storage information, see specific product information within the How Supplied section.
Route-Specific Administration
Topical Administration
-Before applying, the affected areas should be thoroughly washed (using mild soap or soapless cleansing lotion) and patted dry.
-Do not apply to the eye; avoid contact with the mouth, eyes, and other mucous membranes. If contact with the eye(s) occur, the eye(s) should be washed with large amounts of water; contact prescriber if ocular irritation persists.
-Occlusive dressings or wrappings should not be used.
-Wash hands immediately after applying.
Cream/Ointment/Lotion Formulations
-Apply cream and massage gently into the affected areas.
Other Topical Formulations
Gel Formulation
-Apply gel and massage gently into the affected areas
-Cosmetics may be applied after gel has dried.
-Instruct patients to avoid use of alcoholic cleansers, tinctures and astringents, abrasives and peeling agents.
Foam Formulation
-Shake well before use.
-Dispense the smallest amount of foam required to cover the area to be treated (entire face) with a thin layer.
-Instruct patient to avoid flame, fire, or smoking during an immediately after application. The propellant in the foam is flammable. Do not puncture or incinerate the container.
-Cosmetics may be applied after foam has dried.
-Instruct patients to avoid use of alcoholic cleansers, tinctures and astringents, abrasives and peeling agents.
-This product is flammable; avoid heat, flame, or smoking during and immediately following application of the foam.
Most side effects occurring with the use of azelaic acid are mild dermatologic adverse reactions. These effects include burning sensation or stinging (1% to 16%), paresthesias or tingling (1% to 6.2%), pruritus (1% to 6%), xerosis (dry skin, up to 5%), erythema (up to 2%), skin irritation (less than 2%), contact dermatitis (up to 1%), edema (up to 1%), acne vulgaris (up to 1%), rash (less than 1%), and peeling (less than 1%). In patients with dark complexions, skin hypopigmentation may occur. The following additional adverse reactions have rarely been reported: vitiligo, depigmentation, small depigmented spots, hypertrichosis, reddening (signs of keratosis pilaris), and exacerbation of recurrent herpes viral infection (i.e., herpes labialis).
Postmarketing use of azelaic acid has been associated with an application site reaction (i.e., rash), development of hypersensitivity reactions (including angioedema, ocular inflammation, facial swelling, and urticaria) and asthma exacerbation (i.e., dyspnea, wheezing). In addition, cases of iridocyclitis, or inflammation of the iris, have been noted following accidental exposure of the eye to the topical gel. Due to the voluntary nature of postmarketing reports, neither a frequency nor a definitive causal relationship can be established.
Azelaic acid products that contain propylene glycol should be avoided in patients with a known propylene glycol hypersensitivity; avoid use in patients hypersensitive to any other ingredients of the particular formulation prescribed.
Azelaic acid has not been well-studied in patients with dark complexions and should be used cautiously in these patients to avoid hypopigmentation.
Avoid the use of an occlusive dressing or wrap with azelaic acid. Ocular exposure to the drug may cause irritation to the eyes; avoid accidental contact with the eyes, mouth, or other mucous membranes. If contact with the eye(s) occur, the eye(s) should be washed with large amounts of water; patients should contact their physician if ocular irritation persists.
There are no adequate and well-controlled studies regarding the use of azelaic acid during human pregnancy; however, the drug is minimally absorbed systemically following topical administration, and maternal use is not expected to result in fetal drug exposure. In animal reproduction studies, embryofetal toxicity was noted when azelaic acid was administered orally during organogenesis at doses 162-, 19-, and 65-times the maximum recommended human dose in rats, rabbits, and monkeys, respectively. Maternal toxicity was noted at these doses but no malformations were observed in these embryofetal developmental studies.
Azelaic acid is naturally present in human milk. When used as prescribed, the drug is unlikely to be absorbed through the skin in clinically relevant amounts to cause a change in azelaic acid concentrations in milk or affect milk production; therefore, breast-feeding is not expected to result in infant drug exposure. Consider the benefits of breast-feeding, the risk of potential infant drug exposure, and the risk of an untreated or inadequately treated condition. If a breast-feeding infant experiences an adverse effect related to a maternally administered drug, health care providers are encouraged to report the adverse effect to the FDA.
The safety and effectiveness of azelaic acid cream and gel formulations in neonates, infants, and children under 12 years of age have not been established. The foam formulation is not approved for use in pediatric patients less than 18 years of age.
Do not apply azelaic acid to areas affected by herpes labialis; exacerbations of herpes infection have been reported.
Worsening or deterioration of asthma has been observed in patients treated with azelaic acid. Instruct drug recipients to contact their physician if signs of an asthma exacerbation (i.e., dyspnea, wheezing) develop during therapy.
The propellant in azelaic acid topical foam is flammable. Instruct patients to avoid fire, flame, and tobacco smoking during and immediately following application.
The following organisms are generally considered susceptible to azelaic acid in vitro: Propionibacterium acnes, Staphylococcus epidermidis.
Per the manufacturer, this drug has been shown to be active against most strains of the following microorganisms either in vitro and/or in clinical infections: Cutibacterium acnes, Staphylococcus epidermidis
NOTE: The safety and effectiveness in treating clinical infections due to organisms with in vitro data only have not been established in adequate and well-controlled clinical trials.
For the treatment of mild-to-moderate inflammatory acne vulgaris:
Topical dosage (20% cream):
Adults: Apply a thin layer topically to the affected skin area(s) twice daily. The duration of treatment can vary among individuals and depend on the severity of the acne. Improvement occurs in the majority of persons within 4 weeks.
Children and Adolescents 12 to 17 years: Apply a thin layer topically to the affected skin area(s) twice daily. The duration of treatment can vary among individuals and depend on the severity of the acne. Improvement occurs in the majority of persons within 4 weeks.
For the treatment of the inflammatory lesions of mild-to-moderate acne rosacea:
Topical dosage (15% gel or foam):
Adults: Apply a thin layer topically to the entire face (i.e., forehead, chin, nose, and each cheek) twice daily. Reassess the diagnosis if no improvement occurs after 12 weeks of treatment.
For the treatment of melasma*:
Topical dosage (20% cream):
Adults: Limited clinical data exist on the use of azelaic acid in treating melasma. Several studies suggest that azelaic acid 20% cream applied in a thin film to the affected area twice daily in combination with a broad spectrum sunscreen was either more effective than or equally effective as hydroquinone 2% or 4%, respectively.
For the treatment of lentigo maligna* in which surgery is contraindicated:
Topical dosage (cream or ointment 15-35%):
Adults: Application of azelaic acid cream or ointment (15% to 35%) 2 to 4 times per day for 3 to 16 months was used in preliminary uncontrolled studies of lentigo maligna. Response rates were variable with complete resolution in 27 patients (n = 50) in one study to only partial improvement in 2 patients (n = 15) in another study. Since surgery is the primary treatment modality for lentigo maligna it has been suggested that azelaic acid be limited to treating lentigo maligna in patients who are not candidates for surgery.
For the treatment of cutaneous malignant melanoma*:
Topical and Oral* dosage:
Adults: In a preliminary uncontrolled study of patients (n = 23) with cutaneous malignant melanoma, oral therapy (10 to 15 g/day) was combined with topical therapy (15% cream applied twice daily) for 2 to 12 weeks prior to surgical excision. Beneficial clinical effects were noted in all patients and included a progressive reduction in the intensity of lesion pigmentation, arrest and subsequent regression of the advancing edge of the lesion, and flattening of nodular areas. Six patients with single local lesions had clinical remission after approximately 10 years of follow-up. Oral doses of up to 4,000 mg/kg have been administered with no apparent toxicity.
Maximum Dosage Limits:
No maximum dosage information is available.
Patients with Hepatic Impairment Dosing
No dosage adjustments are needed.
Patients with Renal Impairment Dosing
Specific guidelines for dosage adjustments in renal impairment are not available; it appears that no dosage adjustments are needed.
*non-FDA-approved indication
There are no drug interactions associated with Azelaic Acid products.
The efficacy of azelaic acid in acne vulgaris is due to an antimicrobial effect and an antikeratinizing effect on the follicular epidermis. The antimicrobial effects of azelaic acid involves inhibition of synthesis of microbial cellular proteins; the exact mechanism of action is unknown. Azelaic acid possesses bacteriostatic properties against a variety of aerobic microorganisms, especially Staphylococcus epidermidis and Propionibacterium acnes which are known to be elevated in acne-bearing skin; at high concentrations, azelaic acid is bactericidal against S. epidermidis and P. acnes. By reducing the concentration of bacteria present on the skin, azelaic acid decreases the inflammation associated with acne lesions. Azelaic acid may also possess a direct antiinflammatory effect by scavenging oxygen radicals. The antikeratinizing effects of azelaic acid may be due to decreased synthesis of filaggrin (keratin filament aggregating protein). By inhibiting filaggrin, azelaic acid may normalize the keratinization of the follicle and produce a reduction in noninflamed acne lesions. Azelaic acid does not affect sebum excretion.
The mechanism of action that results in the efficacy of azelaic acid in acne rosacea is not clear; clinical studies suggest interference with the pathogenic effects in rosacea. Anti-inflammatory effects have been noted in vitro.
The antiproliferative and cytotoxic actions of azelaic acid may be due to reversible inhibition of a variety of oxidoreductive enzymes including DNA polymerase, tyrosinase, and mitochondrial enzymes of the respiratory chain. At the cellular level, azelaic acid causes mitochondrial swelling and accumulation of cytoplasmic lipid droplets. Azelaic acid has shown efficacy in treating such conditions as lentigo maligna, cutaneous malignant melanoma, and melasma (chloasma). When azelaic acid is applied topically in these conditions, there is a reduction in epidermal melanogenesis and replacement of abnormal melanocytes by normal cells; flattening of nodular areas may also occur. Hyperactive and malignant melanocytes are much more susceptible to the effects of azelaic acid than are normal melanocytes.
Azelaic acid is applied topically to the skin. Azelaic acid is mainly excreted unchanged in the urine but does undergo some beta-oxidation to shorter chain dicarboxylic acids. Plasma concentrations and daily urinary excretion of azelaic acid are highly dependent on dietary intake.
-Route-Specific Pharmacokinetics
Oral Route
The observed half-lives in healthy subjects are approximately 45 minutes after oral dosing, indicating percutaneous absorption rate-limited kinetics.
Topical Route
Following a single application to human skin in vitro, the drug penetrates into the stratum corneum (approximately 3-5% of the applied dose) and other viable skin layers (up to 10% of the dose is found in the epidermis and dermis). Approximately 4% of the topically applied dose is absorbed systemically. Negligible cutaneous metabolism occurs after topical administration. The observed half-lives in healthy subjects are approximately 12 hours after topical dosing, indicating percutaneous absorption rate-limited kinetics. Following topical administration, plasma concentrations and urinary excretion of azelaic acid are not significantly different from baseline levels.