How to introduce retinoids — a methodical approach to starting without irritation.

Retinoids are the most thoroughly studied topical actives for skin ageing and acne. The evidence base is substantial and consistent across decades of research. They are also, in practice, the most commonly misused category of skincare ingredient — causing unnecessary irritation, barrier disruption, and discontinuation in people who would otherwise benefit from them.

Starting correctly matters more than starting fast.

What retinoids do

Retinoids work primarily by binding to nuclear retinoic acid receptors (RARs) and regulating gene expression. This affects multiple skin functions simultaneously: cell turnover accelerates (speeding the transit of skin cells from the basal layer to the surface), collagen synthesis increases, and melanin distribution becomes more even. These effects produce measurable improvements in fine lines, texture, tone, and — for retinoids applied topically at sufficient concentration — acne.

The clinical evidence for tretinoin (the prescription retinoid, also called retinoic acid) is unambiguous. The evidence for retinol (the OTC form) is strong, though weaker than for tretinoin because retinol must be converted to retinaldehyde and then to retinoic acid in the skin — a two-step enzymatic process that reduces the effective dose delivered.

The retinoid ladder

The retinoid family, in rough order of potency and conversion requirements:

Retinyl esters (retinyl palmitate, retinyl acetate) — requires three conversion steps. Lowest effective dose. Most gentle. Appropriate for very sensitive skin or as an introductory form.

Retinol — requires two conversion steps. The standard OTC retinoid. Most widely available and well-studied in the OTC category.

Retinaldehyde — requires one conversion step. More potent than retinol, gentler than tretinoin. Less available but increasingly present in commercial formulations.

Tretinoin (retinoic acid) — no conversion required. Prescription in most markets. The gold standard. Significantly more effective than OTC retinoids at equivalent concentrations.

Adapalene (a synthetic retinoid) — available OTC in some markets. Primarily indicated for acne. Less irritating than tretinoin, with comparable efficacy for comedonal acne.

Why retinoid irritation happens

Retinoid dermatitis — characterised by dryness, flaking, redness, and tightness — is not an allergic reaction. It is a predictable consequence of the accelerated cell turnover retinoids induce, combined (in the early weeks) with the skin's adjustment to a new biological signal.

The irritation is most pronounced in the first two to six weeks. It is worse when:

• The concentration is too high for the skin's current tolerance
• Application frequency is too high (daily from day one)
• The skin barrier is already compromised
• Drying cleansers or exfoliating acids are used concurrently

Most people who abandon retinoids do so because they ignored one or more of these factors.

How to start

Step one: stabilise the barrier first. If the skin is dry, reactive, or currently sensitised, address this before introducing a retinoid. A well-functioning barrier tolerates retinoids significantly better than a compromised one.

Step two: start low and slow. Begin with 0.025–0.05% retinol (or retinaldehyde if available), applied once or twice per week. Not every night. Once or twice per week. Increase frequency incrementally — adding one night per week every four to six weeks — based on how the skin responds.

Step three: buffer if needed. Applying retinol over moisturiser rather than directly to cleansed skin reduces the penetration rate and irritation. This is not optimal for efficacy, but it allows the skin to acclimatise. As tolerance builds, transition to applying on dry skin.

Step four: do not layer other actives. During the acclimatisation period, avoid using exfoliating acids (AHAs/BHAs) and vitamin C on the same night as retinol. This is not because the combinations are chemically problematic — it is because barrier disruption from two actives in combination is greater than either alone.

Step five: use SPF daily. Retinoids increase photosensitivity. This is not optional. Daily SPF 30+ in the morning is the non-negotiable companion to any retinoid routine.

What to expect

In the first month: possible mild flaking and dryness. This is normal.

In months two to three: skin adjusts. The irritation typically resolves. Some people see initial texture improvements.

In months three to six: measurable improvements in tone, fine lines, and texture become apparent with consistent use. This is the realistic timeline.

Beyond six months: continued, cumulative improvement with consistent use. Retinoids work slowly. The results are real and lasting.

The Lux & Glo position

Retinoids are not part of the foundational ritual. The three-step routine — cleanse, treat with niacinamide, hydrate — is designed as the stable baseline that makes the barrier robust enough to tolerate a retinoid when and if it is introduced.

Niacinamide and retinol are compatible and often used together. Niacinamide's barrier-strengthening and anti-inflammatory effects reduce the retinoid irritation that occurs in the acclimatisation period. For many people, this combination — a stable barrier routine plus a carefully introduced retinoid — is the most effective long-term strategy.

The principle holds: one variable, introduced slowly, on stable skin.