Tretinoin (Topical)

• Acne Vulgaris
• Fine Wrinkles
• Photoaging
• Comedonal Acne

Tretinoin topical is a retinoid (vitamin A derivative) used to treat acne vulgaris and as an adjunctive treatment for sun-damaged skin. It is one of the most effective topical treatments for acne and has additional anti-aging benefits.

Mechanism of Action

Tretinoin works through retinoid receptor activation:

• Retinoid receptor binding: Binds to retinoic acid receptors (RARs) in keratinocytes
• Modulates gene transcription: Alters expression of genes involved in cell proliferation and differentiation
• Normalizes follicular keratinization: Prevents abnormal keratinization that causes comedones
• Promotes comedone expulsion: Helps clear existing comedones
• Reduces microcomedone formation: Prevents new acne lesions
• Stimulates collagen synthesis: Improves photodamaged skin appearance

Available Formulations

• Cream: 0.025%, 0.05%, 0.1%
• Gel: 0.01%, 0.025%, 0.05%
• Microsphere gel (Retin-A Micro): 0.04%, 0.08%, 0.1%
• Lotion: 0.05%

Medical Uses

FDA-Approved Indications:

• Acne vulgaris
• Adjunctive treatment for mitigation of fine wrinkles, mottled hyperpigmentation, and roughness of facial skin (0.05% cream)

Dosing Guidelines

Acne:

• Apply a pea-sized amount once daily in the evening to clean, dry skin
• Start with lower concentration and increase as tolerated
• Initial improvement may take 8-12 weeks

Photodamaged Skin:

• Apply 0.05% cream once daily to face in the evening
• Use in conjunction with comprehensive sun avoidance

Application Tips:

• Apply 20-30 minutes after washing face
• Avoid eyes, mouth, nasal creases, mucous membranes
• Use non-comedogenic moisturizer as needed
• Always use sunscreen during the day

Important Safety Information

Contraindications:

• Hypersensitivity to tretinoin or any component
• Sunburn (allow to heal first)

Warnings and Precautions:

• Photosensitivity: Significantly increases sun sensitivity; use sunscreen and protective clothing
• Skin irritation: Erythema, peeling, burning common initially
• Weather extremes: Avoid excessive cold, wind, or dry conditions
• Waxing: Avoid on treated areas
• Other irritating products: Use cautiously with other topical medications

Drug Interactions

• Other topical products containing sulfur, resorcinol, benzoyl peroxide, salicylic acid: May increase irritation; use with caution
• Photosensitizing medications (thiazides, tetracyclines, fluoroquinolones): Augmented photosensitivity
• Topical products with high alcohol content: Increase drying and irritation
• Abrasive soaps and cleansers: Increase irritation

Special Populations

• Pregnancy: Contraindicated (Category C, but topical absorption is minimal; oral retinoids are teratogenic)
• Lactation: Unknown if excreted in milk; use with caution
• Pediatric: Safety and efficacy established for acne treatment
• Elderly: No specific adjustment; may be more sensitive to irritation
• Darker Skin Types: Higher risk of post-inflammatory hyperpigmentation; start with lower strength