Tretinoin for Photoaged Skin: Landmark RCT
New England Journal of Medicine (1988)
Kligman et al. demonstrated 0.05% tretinoin significantly improved fine wrinkles, hyperpigmentation, and rough texture over 16 weeks vs vehicle.
How it works
Marek's Guided Optimization® Program combines advanced lab testing, a dedicated health coach and medical provider, and a personalized treatment plan, all built around your data.
Resources
The process
1
Start your assessment
Complete your 45-min intake assessment
2
Get your labs drawn
4,000 partnered lab locations nationwide
3
Review with your coach
Screen-by-screen lab review
4
Receive your protocol
Treatment delivered to your door
Why Marek
The only program pairing you with a dedicated health coach and medical provider, built on precision diagnostics, with no subscription required.
Resources
Meet our co-founder
Derek
Co-Founder · MPMD Podcast
"Over time, I found it incredibly difficult to get medical oversight for myself and my family that reflected the latest research, and that was preventative. That's why I started Marek Health."
Excellent on Trustpilot
What we test
Every client's lab panel is hand-selected from 1,000+ available biomarkers, built around their specific goals.
Panel categories
Resources
Treatments
700+ medical provider-prescribed therapies built from your labs. Browse by category or explore the full formulary.
Tretinoin (Retin-A)
Topical cream (0.025%), Component of multiple Marek dermatology formulationsAvailable in all 50 statesMarketing purposes only. Actual medications, if prescribed, are dispensed by a licensed pharmacy.
skin
Tretinoin (Retin-A)Tretinoin (Retin-A)
Gold standard topical retinoid for photoaging and acne. Increases epidermal cell turnover, stimulates collagen synthesis, and reduces fine wrinkles, mottled pigmentation, and rough texture. Most evidence-supported topical anti-aging ingredient.
Most evidence-supported topical anti-aging agent
Increases collagen synthesis
Reduces fine wrinkles and pigmentation
Improves skin texture
No commitment · HSA/FSA eligibleNo commitment · HSA/FSA eligible
How it works
Mechanism of action
Binds nuclear retinoic acid receptors (RAR-α, β, γ), modulating gene transcription to increase epidermal proliferation, promote orderly desquamation, stimulate dermal collagen synthesis, and inhibit matrix metalloproteinases that degrade collagen.
The baseline panel.
Every Marek client receives this baseline panel before a provider review. Your provider may add additional biomarkers based on your health history, symptoms, and goals, pulling from 1,000+ available markers. See more biomarkers →
Hormone Profile
12 markers
Sex hormones
- Total TestosteroneLC/MS
- Free TestosteroneEquilibrium Dialysis
- Estradiol, Sensitive / UltrasensitiveLC/MS
- Sex Hormone Binding Globulin (SHBG)
- ProgesteroneLC/MSFemale panel
- Prolactin
- Luteinizing Hormone (LH)
- Follicle-Stimulating Hormone (FSH)
- hCG, Total, QuantitativeFemale panel, pre-menopause
Adrenals & neurosteroids
- Cortisol
- DHEA-S
Growth hormone / IGF-1
- Insulin-Like Growth Factor I (IGF-1)
Thyroid Status
3 markers
Thyroid hormones
- Thyroid Stimulating Hormone (TSH)
- Free T4
- Free T3
Heart Health
9 markers
Cardiovascular health
- Total Cholesterol
- HDL Cholesterol
- LDL Cholesterol
- LDL:HDL Ratio
- VLDL Cholesterol
- Triglycerides
- Apolipoprotein-B (ApoB)
- C-Reactive Protein, High Sensitivity (hsCRP)
- Lipoprotein(a) (Lp(a))
Metabolism
3 markers
Insulin sensitivity
- Blood Glucose
- Fasting Insulin
- HbA1c
Organ Function
26 markers
Liver & pancreas
- AST
- ALT
- Bilirubin, Total
- γ-Glutamyl Transferase (GGT)
Kidney function
- BUN
- Creatinine w/ eGFR
Comprehensive Metabolic Panel (CMP)
- Glucose
- Blood Urea Nitrogen (BUN)
- Creatinine
- eGFR
- BUN/Creatinine Ratio
- Sodium
- Potassium
- Chloride
- Carbon Dioxide, Total
- Calcium
- Protein, Total
- Albumin
- Globulin, Total
- Albumin/Globulin (A/G) Ratio
- Alkaline Phosphatase (ALP)
- AST
- ALT
Prostate health
- Prostate-Specific Antigen (PSA)Male panel
- Free PSAMale panel
- % Free PSAMale panel
Nutrient Status
31 markers
Vitamins & minerals
- Vitamin D, 25-OHD (25-Hydroxy)
- Magnesium, RBC
Iron status
- Iron
- Iron Saturation
- TIBC
- UIBC
- Ferritin
Complete Blood Count (CBC)
- White Blood Count (WBC)
- Red Blood Count (RBC)
- Hemoglobin (Hgb)
- Hematocrit (HCT)
- MCV
- MCH
- MCHC
- Red Cell Distribution Width (RDW)
- Platelets
- Neutrophils
- Neutrophils (Absolute)
- Lymphocytes
- Lymphocytes (Absolute)
- Neutrophil/Lymphocyte Ratio
- Monocytes
- Monocytes (Absolute)
- Eosinophils
- Eosinophils (Absolute)
- Basophils
- Basophils (Absolute)
- Immature Cells
- Immature Granulocytes
- Immature Granulocytes (Absolute)
- NRBC, w/ Reflex for Immature Cells
Clinical evidence
The research behind Tretinoin (Retin-A).
Safety profile
Monitoring & safety information.
Commonly reported side effects
- Skin irritation/peeling (retinoid dermatitis)
- Dryness
- Erythema
- Photosensitivity
- Initial purging (acne)
Less common but serious risks
- Teratogenicity (topical risk low but avoid in pregnancy)
- Severe irritation if overused
Generally not appropriate for
- Pregnancy
- Concurrent use with other strong irritants
Typical monitoring
- Skin tolerance assessment
- Sun protection counseling
- Pregnancy prevention
FAQ
Quick answers.
Gold standard topical retinoid for photoaging and acne. Increases epidermal cell turnover, stimulates collagen synthesis, and reduces fine wrinkles, mottled pigmentation, and rough texture. Most evidence-supported topical anti-aging ingredient.
Most evidence-supported topical anti-aging agent. Increases collagen synthesis. Reduces fine wrinkles and pigmentation. Improves skin texture. Decades of safety data.
Common side effects include: skin irritation/peeling (retinoid dermatitis), dryness, erythema, photosensitivity, initial purging (acne). Most side effects are dose-dependent and may resolve with continued use or dose adjustment.
Gold standard topical retinoid for photoaging and acne. Increases epidermal cell turnover, stimulates collagen synthesis, and reduces fine wrinkles, mottled pigmentation, and rough texture. Most evidence-supported topical anti-aging ingredient.
Treatments are dependent on licensed clinical prescription. Client costs vary based on individual labs and panel in treatments and services.