Video summary

The TRUTH About Azelaic Acid | Dermatologists Explain

Main summary

Key takeaways

Science and Nature

Scientific concepts / nature & medical phenomena mentioned

Azelaic acid (dermatologist-used ingredient)

  • Used for acne, dark spots (hyperpigmentation), and rosacea.
  • Presented as pregnancy-safe (relative claim).
  • Described as a naturally occurring ingredient produced from yeast associated with skin conditions.

Chemical behavior: azelaic acid is a diprotic acid

Azelaic acid is a dicarboxylic (two-proton) acid, losing protons in two pH-dependent steps:

  • pKa ~4.5: first proton loss begins; below ~4.5 it’s mostly in the acid form.
  • pKa ~5.3: second proton loss; above ~5.3 it becomes more fully ionized/salt-like.

Formulation science: “suspended” vs “solubilized” azelaic acid

Two formulation modes are contrasted:

  • Suspended particles (“snow globe” analogy)

    • At lower pH, azelaic acid has poor solubility, so particles remain undissolved and can feel gritty.
    • Often associated with stinging/burning and less comfortable texture.

  • Dissolved (solubilized) azelaic acid

    • At higher pH, azelaic acid dissolves more due to increased ionization.
    • Often associated with a watery/smoother texture.

Role of excipients / solvents

Higher-pH solubilization may require additional solubilizers, with concerns raised in the subtitles:

  • One brand uses propylene glycol, which is described as a common allergen.
  • Another brand uses pure alcohol to dissolve azelaic acid (as stated).

Skin barrier physics: size and charge affect penetration

The skin barrier is described as resisting molecular passage based on:

  • Molecular size (too large can’t pass)
  • Charge/ionization (more ionized = more charge = less likely to pass)

A “dogma” from pharma is mentioned:

  • The nonionized (lower pH) form is often expected to penetrate better because it’s less charged.
  • However, solubility and formulation can counteract that expectation.

Mechanism/efficacy depends partly on penetration and partly on surface activity

For acne and rosacea, targets may be near the surface rather than deep, so some effects may not require deep absorption.

Key research concept: penetration studies comparing pH states

A referenced study compares azelaic acid in different pH environments:

  • pH 3.9: more “suspended,” nonionized, less charged
  • pH 4.9: more “solubilized,” higher ionization/charge

As presented in the video:

  • The higher-pH solubilized preparation shows better penetration/absorption and higher flux into skin.
  • The “debate” is framed as resolving toward higher-pH solubilized formulations being more effective in that study context.

“Online scam” concern may be nuanced: skin pH can shift chemical state

The video argues that when the product contacts skin (skin pH ~5 due to the acid mantle), azelaic acid may reversibly shift between ionized and nonionized forms.

Proposed model:

  • The molecule “fluxes” back and forth depending on the local pH environment.
  • Therefore, the salt vs acid state in the bottle may still convert on the skin.

A visual demo is used:

  • One arm shows white flaking/crystallization when the formula is left to change/aggregate.
  • The other arm shows no flaking when applied normally, implying formulation behavior during spreading/release differs.

Overall thesis: formulation complexity can override single-ingredient/pH assumptions

The video argues it’s not just “ingredient + pH”, but how formulation affects skin interaction and delivery.

Regulatory differences are also mentioned:

  • Pharmaceutical drugs are described as having more rigorous studies than cosmeceuticals/OTC cosmetics.

Lists / methodology-style outline (as described)

Experimental/visual procedure demonstrated on arms

  • Apply two azelaic-acid preparations to arms:
    • “Solubilized azelaic acid” to one arm; do not rub—allow it to drip and “cook.”
    • “Azelaic acid” to the other arm; rub in normally.
  • Observe differences:
    • Crystallization/flaking vs no visible residue.

Study comparison framework (from pharma literature as described)

Compare azelaic acid delivery forms by controlling:

  • pH (e.g., 3.9 vs 4.9)
  • state (suspended nonionized vs solubilized ionized)

Measure:

  • penetration/absorption
  • flux (into skin)
  • comparative efficacy

Researchers / sources featured (named in subtitles)

  • Dr. Dr. Maxfield (presenter; appears as “Dr. Dr. Maxville” in subtitles)
  • Dr. Shaw (referenced as a collaborator/other dermatologist in discussion)
  • Marina (cosmetic chemist referenced; “Substack” author mentioned)
  • A linked pharma paper is referenced but not named (no author/journal details provided).

Original video