Active ingredients: when more is not better.

01 / What the word covers

What counts as an active.

In everyday skincare, an active ingredient is one included to produce a specific change, as opposed to the ingredients that give a product its texture or keep it stable. Retinol and other retinoids, exfoliating acids, vitamin C, benzoyl peroxide and niacinamide are the names most people mean.

These ingredients are the reason many products exist. They are also the ones most likely to be felt on the skin. The American Academy of Dermatology notes that some products contain active ingredients that can cause problems if you apply more than directed, including clogged pores, blotchy skin or excessive dryness.[1]

A product does not need an active to be worth using. A plain cleanser and a comfortable moisturiser carry out their jobs without one, which is why they form the base of a simple skincare routine.

02 / How routines fill up

Three ways a routine becomes crowded.

Few people set out to use six actives. It tends to happen one reasonable purchase at a time.

Overlap

Two or three products aimed at the same concern: an exfoliating cleanser, an acid toner and a peeling mask in one week. Each seems mild; together they add up.

Stacking

Several different actives layered in a single evening because each promises something separate. The skin receives all of them at once.

Switching

A new product every week or two, before the last one has had time to show anything. The AAD lists this habit among those that can irritate skin and lead to breakouts in people treating acne.[6]

The AAD’s advice on anti-ageing products is direct: using several at the same time can irritate your skin, and irritated skin makes signs of ageing more noticeable.[1][5] The products were bought to improve the skin, and the combination produces the opposite effect.

There is a second cost. With several actives in play, you cannot tell which one is responsible for an improvement or a reaction, and understanding what your skin needs becomes harder.

03 / Reading the response

Signs the routine is asking too much.

Skin that is being pushed too hard usually says so. Watch for:

• Stinging or burning when you apply products that used to feel comfortable.
• Tightness, flaking or peeling that was not there before.
• Redness that lingers after application.
• New breakouts shortly after adding or increasing a product.

The AAD’s guidance is to stop using a product that stings, burns or tingles, because those sensations mean it is irritating your skin. The exception is a prescription product: ask the dermatologist who prescribed it whether the sensation is expected before you stop.[1]

It is tempting to read tingling as proof that something is working. Tingling is not a reliable sign of benefit. If the reaction is new and you are unsure whether it is the product or your skin, the guide to sensitive skin or a routine that has become too much covers how to separate the two.

04 / A narrower plan

One concern, one active, enough time.

The AAD suggests starting with sunscreen and moisturiser, then choosing a single concern to treat. Its reasoning is that no product can treat every sign of skin ageing, and using more than one such product within a few days or weeks can irritate the skin.[2]

1. Name the concern.

   Uneven tone, breakouts and fine lines are different goals. Pick the one that matters most to you now. The others can wait their turn.

2. Choose one product for it.

   Look for a product intended for that concern and suited to your skin. Higher strength is not automatically more useful; with niacinamide, for example, a higher percentage does not guarantee more benefit, and the same question applies when choosing a vitamin C serum.

3. Follow the directions.

   Use the amount and frequency on the label. Applying more than directed is one of the ways actives cause trouble.[1]

4. Give it time.

   According to the AAD, a moisturiser can plump fine lines within days, but most products take at least six weeks to work and some take up to three months.[1] Changing course at week two tells you very little.

When you do add something, introduce the new product on its own so that any response can be traced to it.

05 / Where care is needed

Combinations that deserve caution.

Some pairings come up again and again in routine reviews. None of the notes below is a rule for every skin; they are reasons to slow down and, where relevant, to ask.

Retinoids and exfoliants

The AAD points out that retinoid creams, retinol and benzoyl peroxide can already make skin more sensitive or cause peeling, and that exfoliating while using them may worsen dryness or cause breakouts.[4] See retinol and exfoliating acids.

Starting a retinoid

Dermatologists quoted by the AAD advise the least intense formula you can find, used every other night at first and built up slowly. Retinoids can make skin more sensitive to the sun, so they are used at night with sun protection during the day.[3] Read the questions to ask before starting retinol.

Dry or reactive skin

The AAD notes that people with skin allergies or dryness are probably not good candidates for retinoid products, and that marked redness is a reason to ask a dermatologist about other options.[3]

Pregnancy

Retinoids should not be used during pregnancy.[3] Review the rest of your routine with your clinician; see pregnancy and skincare and breastfeeding and skincare.

Other combinations are more about comfort than risk. Whether you can use vitamin C and niacinamide together is a common question with a calmer answer than the internet suggests. Ingredients such as peptides and azelaic acid have their own guides, as does slugging, which can change how other products feel on the skin.

06 / Knowing the limit

When a product question becomes a medical one.

Most crowded routines settle once the number of actives comes down. Some situations need more than a simpler shelf.

For anything short of that, a skincare consultation is a place to talk through what you use and what you hope it will do. Merve Akkaya’s approach begins with the purpose of each step.

A few common questions

Frequently asked questions.