Usage
- Azelaic acid is prescribed for the topical treatment of mild to moderate inflammatory acne vulgaris and the inflammatory papules and pustules of mild to moderate rosacea. It reduces inflammation and the production of keratin, a protein that contributes to acne. It may also be used to treat hyperpigmentation (melasma).
- Pharmacological Classification: Azelaic acid is classified as a dicarboxylic acid, and exerts anti-inflammatory, antibacterial, and keratolytic effects.
Alternate Names
- While “azelaic acid” is the standard generic name, it is marketed under brand names such as Azelex and Finacea.
How It Works
- Pharmacodynamics: Azelaic acid’s primary mechanism of action involves inhibiting the growth of Propionibacterium acnes and Staphylococcus epidermidis, bacteria associated with acne. It also exhibits anti-inflammatory properties, reduces the production of reactive oxygen species, and interferes with keratinocyte proliferation, thereby preventing clogged pores.
- Pharmacokinetics: Azelaic acid, when applied topically, is minimally absorbed into the systemic circulation. Approximately 4% is absorbed percutaneously. Absorbed azelaic acid is primarily excreted unchanged in urine. A small portion is metabolized via beta-oxidation to shorter-chain dicarboxylic acids. The half-life is about 12 hours after topical application.
- Mode of action: The mechanism by which azelaic acid exerts anti-inflammatory action is by scavenging reactive oxygen species and inhibiting the production of proinflammatory cytokines. It also inhibits thioredoxin reductase in mitochondria, which decreases cellular respiration and reactive oxygen species formation.
- Elimination Pathways: Primarily renal excretion (unchanged drug and metabolites).
Dosage
Standard Dosage
Adults:
- Acne: Apply a thin layer of 20% cream to the affected area twice daily (morning and evening).
- Rosacea: Apply a thin layer of 15% gel or foam to the affected area twice daily (morning and evening).
Children:
- Acne: 20% cream is indicated for ages 12 years and older, applied twice daily. For children under 12, consult a doctor.
- Rosacea: Safety and efficacy have not been established for children younger than 12 years old.
Special Cases:
- Elderly Patients: Dosage adjustments are generally not necessary.
- Patients with Renal Impairment: No specific dosage adjustments are generally needed, as systemic absorption is minimal.
- Patients with Hepatic Dysfunction: No specific dosage adjustments are generally needed.
- Patients with Comorbid Conditions: Consider pre-existing skin conditions and sensitivities.
Clinical Use Cases
Azelaic acid’s clinical use is limited to topical application for dermatological conditions like acne and rosacea. It is not indicated for:
- Intubation
- Surgical Procedures
- Mechanical Ventilation
- Intensive Care Unit (ICU) Use
- Emergency Situations
Side Effects
Common Side Effects:
- Burning, stinging, itching, or tingling at the application site (typically mild and transient).
- Dryness, scaling, or redness of the skin.
Rare but Serious Side Effects:
- Allergic reactions (e.g., hives, difficulty breathing, swelling).
- Worsening of asthma or other breathing problems.
- Severe skin irritation or changes in skin color.
Long-Term Effects:
- Hypopigmentation (skin lightening), especially in patients with darker skin tones.
Contraindications
- Hypersensitivity to azelaic acid or any component of the formulation.
Drug Interactions
- Minimal drug interactions are expected due to low systemic absorption.
Pregnancy and Breastfeeding
- Pregnancy Category B: Animal studies have not shown fetal harm, but adequate human data is lacking. Use during pregnancy only if clearly needed.
- Breastfeeding: It is unknown if azelaic acid is excreted in breast milk. Exercise caution when using while breastfeeding.
Drug Profile Summary
- Mechanism of Action: Antibacterial, anti-inflammatory, and keratolytic.
- Side Effects: Burning, stinging, itching, dryness, hypopigmentation (rarely).
- Contraindications: Hypersensitivity.
- Drug Interactions: Minimal.
- Pregnancy & Breastfeeding: Category B; caution advised.
- Dosage: Topical application twice daily.
- Monitoring Parameters: Monitor for skin irritation and signs of hypopigmentation.
Popular Combinations
Azelaic acid may be combined with other topical agents, like benzoyl peroxide or retinoids, for synergistic effects in treating acne. Oral antibiotics may be used in conjunction with azelaic acid for moderate to severe acne or rosacea.
Precautions
- Avoid contact with eyes, nose, and mouth.
- Discontinue use if severe irritation develops.
- Monitor for hypopigmentation in patients with darker skin tones.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Azelaic Acid?
A: The recommended dosage is topical application of 15% gel or foam (for rosacea) or 20% cream (for acne) twice daily.
Q2: How long does it take for Azelaic Acid to work?
A: Improvement may be noticeable within 4 weeks, but full effects may take several months.
Q3: Can Azelaic Acid be used during pregnancy?
A: It’s a Pregnancy Category B drug. Use only if clearly needed and under the guidance of a physician.
Q4: What should I do if I experience skin irritation?
A: Discontinue use and consult your doctor. A lower concentration or less frequent application may be recommended.
Q5: Can I use Azelaic Acid with other acne medications?
A: Yes, but consult your doctor about potential interactions or additive irritation.
Q6: Does Azelaic Acid treat post-inflammatory hyperpigmentation?
A: Yes, it can help fade dark spots left after acne inflammation.
Q7: Can I use makeup after applying Azelaic Acid?
A: Yes, once the medication has dried.
Q8: Is Azelaic Acid a permanent solution for acne or rosacea?
A: It helps control symptoms but is not a cure. Continued use is usually necessary to maintain improvement.
A: The formulations have different bases and may have slightly different absorption and tolerability profiles. The choice often depends on individual skin type and preference.
