Itchy and Sensitive Scalp in Singapore: what is actually irritating it

An itchy scalp is a symptom, not a condition, and that is the whole difficulty with it. At least six different things produce the same sensation, they respond to completely different handling, and the shampoo aisle treats them as one problem. This sets out how to tell them apart.

The six usual causes

A damaged skin barrier

The most common one, and the most self-inflicted. Strong detergents, very hot water, frequent washing with a clarifying shampoo, or two or three actives layered on top of each other all strip the lipids that hold the skin barrier together. A scalp in that state feels tight immediately after washing and itchy a few hours later. It is not infected and it is not allergic. It is raw.

Seborrheic dermatitis

Greasy yellowish scale, redness, and itch that is worse when the scalp is oily. It is associated with Malassezia, a yeast that lives on everyone, and it runs in flares rather than continuously. It frequently appears alongside an oily scalp, which is why the two get confused.

Contact reaction

Something is being applied that the scalp does not tolerate. Fragrance and preservatives are the usual suspects, and hair dye is the big one — particularly paraphenylenediamine, which causes genuine allergic reactions and can do so after years of uneventful use. A contact reaction usually starts within a day or two of the thing that caused it and is worst where the product sat longest, which for dye is the hairline and the nape.

Sweat and occlusion

In this climate, a scalp under a helmet, a cap or a scarf for hours sweats and does not dry. Salt residue on skin is itchy on its own, and the warm damp environment favours the organisms that make it worse.

Dryness from air conditioning

Conditioned air is dry air. Moving between it and the street several times a day is harder on the skin barrier than either condition alone.

Psoriasis

Thick, silvery, well-defined plaques rather than diffuse flaking, often extending past the hairline onto the forehead or behind the ears. This is a medical condition, it is managed rather than cured, and it is a dermatologist’s territory.

How to tell which one you have

Three questions get most people to the right answer.

• Does it feel tight straight after washing? That points at the barrier and at what you are washing with.
• Is there scale, and what does it look like? Greasy and yellowish suggests seborrheic dermatitis. Dry and fine suggests a dry, stripped scalp. Thick and silvery suggests psoriasis.
• Did it start after you changed something? A new shampoo, a colour appointment, a new leave-in. A contact reaction almost always has a date.

If the honest answer is that you cannot tell, that is the normal answer, and it is what the scan exists for.

The mistake almost everyone makes

An itchy scalp feels dirty, so people wash it more and harder, usually with something stronger. If the cause is a damaged barrier — which it most often is — that is precisely the wrong move, and each round makes the next worse.

The second mistake is stacking. A medicated shampoo, a tea tree oil, a scrub and an apple cider vinegar rinse, all in the same week. Even if one of them would have helped, you will never find out which, and the combined load on an already compromised barrier is worse than any of them alone.

The third is scratching, which breaks the skin and gives bacteria an opening. If the itch is bad enough that you cannot leave it alone, that is a reason to see a doctor, not a reason to scratch more carefully.

What actually calms it

At home

Strip the routine back to two things and leave it alone for eight weeks. The Sensitive series is built for a reactive scalp rather than a dirty one — the Sensitive Shampoo cleans without the detergent load, and the Sensitive Tonic stays on the scalp between washes, which is where a calming ingredient has to be to do anything.

Keep conditioner off the roots entirely — the Sensitive Conditioner goes mid-length to ends. Wash in water that is cooler than feels nice. Dry the scalp properly rather than tying hair up damp.

One caution worth stating plainly: every product we make is scented. If fragrance itself is what your scalp reacts to, talk to us before buying anything from this site.

In studio

The Soothing Treatment is the one for this — temperature, pressure and actives all turned down, which is the opposite of what an irritated scalp usually gets. Where there is flaking as well as itch, the Refining Treatment lifts the scale rather than scrubbing at it. Doing the second before the first, on a scalp that is already sore, tends to set it back.

When to see a doctor instead

• The itch wakes you at night, or you cannot stop scratching
• There are open, weeping or crusted areas
• Thick silvery plaques, or patches extending onto the face or behind the ears
• Hair is coming out of the itchy area
• It started within days of a new medication
• It has not moved at all after eight weeks of a gentle, unchanged routine

Psoriasis, eczema, a true allergy and fungal infection all need a diagnosis and, often, a prescription. We work alongside that, not instead of it — and the itching that comes with the first weeks of a prescribed treatment is something we can genuinely help with.

Where to start

Dandruff, a dry scalp and seborrheic dermatitis look much the same in a bathroom mirror and need different handling. The AI scalp scan photographs four zones at high magnification and scores five things, so the answer comes from your own scalp rather than from a guess. It is free, about fifteen minutes, and the first customised treatment is $59 if you decide to go ahead.

If what you actually have is flaking rather than irritation, read our guide to dandruff instead.