Tretinoin (Retin-A)

Topical cream (0.025%), Component of multiple Marek dermatology formulationsAvailable in all 50 states

Marketing 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).

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.

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.
View all FAQs
See all FAQs

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.