Eczema in Sabah: Triggers and How to Manage Them

Sep 12

7 min read

Updated: Sep 29

中文摘要在文末

Most of what's written about eczema on the internet was written for people living somewhere cold.

You'll read about dry winter air, central heating, wool sweaters, hot baths to warm up. And then you're standing in Kota Kinabalu in August, sweating through your shirt before you've reached the shop entrance, wondering why none of it applies to you.

It mostly doesn't. Living in Sabah changes the trigger picture substantially, and after years of seeing patients here I have a fairly clear ranking of what actually causes flares locally. Let me go through them.

1. Sweat and humidity — the number one, by a distance

If I had to name one thing that drives eczema in Kota Kinabalu, it's sweat sitting on skin.

Here's what people get wrong. They think sweat is a hygiene issue — that they're flaring because they're not clean enough. It isn't that. Sweat contains salt and various irritant compounds, and on intact skin that's fine. On skin with a defective barrier, it's a chemical irritant sitting directly on inflamed tissue. Add heat, which itself makes you itch, and add friction from damp clothing, and you have a reliable flare engine running all day.

And the geography here is relentless. You're not hot for three months a year. You're hot in the morning, hot in the car park, hot in that stretch between the office door and where you actually parked.

What to do about it:

Rinse rather than scrub. When you get home sweaty, a quick cool rinse is far better than letting dried sweat sit on the skin all evening — but it should be a rinse, not a full soapy assault. Then re-moisturise while the skin is still slightly damp. That last step is the one people skip.

Cotton over synthetics, and looser rather than tighter. Polyester traps heat and moisture against the skin and adds friction, which is a bad combination for the folds — elbows, knees, neck.

Keep a spare shirt in the bag or the car if your day involves being outdoors. Not glamorous, but it works.

For the folds specifically, drying properly after showering matters more than people think. Damp skin fold plus heat is also how you get fungal infections that look like eczema and get treated as eczema for months, which brings me to something I'll flag now — not everything itchy is eczema, and in this climate the overlap with fungal problems is genuinely common. If your "eczema" has a clear advancing edge and is spreading in a ring, get it looked at rather than reaching for a steroid, because a steroid on a fungal infection makes it worse and disguises it at the same time.

2. Sea water and pool water — cuts both ways

Everyone in Sabah eventually asks me about the beach, and the honest answer is that it depends on the person.

For some people, salt water genuinely helps. Mild antiseptic effect, a bit of drying of weepy areas, and there's a reason seaside holidays have a reputation for helping skin.

For others it's a straight flare, particularly if the skin is already cracked or fissured. Salt in an open fissure is exactly as unpleasant as it sounds, and some people come back from a weekend at the islands with hands considerably worse than when they left.

Chlorinated pools are similar but with more of a drying/irritant effect.

What to do: don't ban the beach. That's a lot to ask of anyone living here, and especially of a child. Instead — apply emollient before going in, which gives some barrier protection, rinse thoroughly with fresh water afterwards, and re-moisturise immediately. Then watch what happens over the next day or two. After two or three trips you'll know which category you fall into, and you can plan accordingly.

3. Dust — the one that hides

This is the trigger that gets missed, because it usually produces a strange pattern rather than an obvious one.

I had a patient with persistent eczema on both ankles. Only the ankles. Nothing on her hands, nothing on her arms, nothing anywhere else. That distribution bothered me, because it didn't fit any of the usual patterns and it wasn't responding the way I'd expect.

So we kept talking. And somewhere in the conversation she mentioned, almost in passing, that her office had been under renovation for the past couple of months. Dust everywhere, settling on the floor, all day, every day — at ankle height. Sitting at a desk, ankles exposed, in a fine layer of construction dust for eight hours.

That was the whole answer. Treatment after that was straightforward.

I tell that story a lot because of what it illustrates. If I had just looked at the ankles, written a prescription and moved on, she'd have kept flaring and I'd have kept escalating treatment for a problem that a five-minute conversation solved. This is precisely why my consultations are roughly ninety percent talking and ten percent prescribing.

What to do: if your eczema has an odd distribution — one area only, or an asymmetric pattern, or something that appeared at a specific point in time — think about what changed. New house. Renovation next door. New sofa. New pet. New job with a different environment. Then tell me, even if it seems irrelevant. The irrelevant details are usually where the answer is.

House dust mites deserve a mention too. Our humidity is excellent for them. If you're already atopic — eczema plus asthma plus allergic rhinitis in the same person or family — mite reduction is worth doing: hot-wash bedding weekly, reduce soft toys in the bed, consider mattress and pillow covers. I'd call this a supporting measure rather than a headline one. It helps some people meaningfully and does very little for others.

4. Aircon — the trigger nobody expects

Sabah is humid outside and often quite dry inside, because aircon strips moisture from the air. So you spend the day cycling between a sweaty environment and a desiccating one, which is harder on a compromised barrier than either would be alone.

I'm not going to tell you to switch off the aircon in Kota Kinabalu. That's not a serious recommendation. But if you're sleeping in a cold, very dry room with the unit blasting all night, and you wake up itchy, that's worth adjusting — a slightly higher temperature, not aiming the vent directly at the bed, and a proper emollient application right before sleep.

5. The everyday chemical stuff

Strongly scented soaps and shower gels. Antibacterial and "medicated" washes, which people with eczema gravitate towards precisely because they feel like the responsible choice, and which are often the most stripping products on the shelf. Fabric softener residue on clothes.

Dishwashing liquid, for hand eczema — this one is huge and very easily fixed with gloves.

Swap to a proper non-soap cleanser and stop letting soap run over the whole body in the shower by default. You need soap on a fairly small number of places. The rest of you is getting clean from the water.

The overall principle

My rule for patients here: clean enough, not too clean.

Malaysians are, generally, very clean people. Two showers a day is normal, often three if you've been out. That's culturally sensible in this heat, and I'm not asking anyone to be dirty. But long, hot, heavily-soaped showers, twice or three times daily, will strip a barrier that's already defective — and then people moisturise on top of skin they've just stripped and wonder why it isn't holding.

So: cooler water, shorter, soap only where it's needed, non-soap cleanser, and moisturise while still slightly damp. Do that consistently and a lot of people find their baseline improves before we've changed a single medication.

When triggers aren't the whole story

One caution. Trigger-hunting can become its own trap. I've met patients who've mapped every exposure in their life, cut out foods, changed detergents, rearranged their house — and are still flaring, because their skin was never properly treated in the first place.

Triggers matter. But the order is: get the skin under control first with proper treatment, then reduce triggers to keep it there. Doing it the other way round means fighting inflammation with lifestyle adjustments alone, which is a slow and demoralising way to lose.

If you want help working out which of these applies to you, come and see me. Klinik Dr Tan (Skin & Acne), Lot 27, Ground Floor, Block D, Lintas Square, Kota Kinabalu. WhatsApp 017-234 7328. Appointments preferred — this kind of consultation needs talking time, and the talking is the part that finds the ankles.

简要说明

我是陈医生，亚庇 Lintas Square 的 Klinik Dr Tan（皮肤与暗疮）。我是对皮肤有专长的普通科医生，不是皮肤专科医生。

网上关于湿疹的资料多数是写给寒带地区的人看的。沙巴的情况不一样。

本地最常见的诱因，按重要性排序：

流汗与潮湿（第一位）。汗水中的盐分对受损的皮肤屏障是刺激物。回家后用清水冲洗（不要用力搓、不要多用肥皂），趁皮肤微湿时立刻涂保湿霜。穿棉质、宽松的衣服。皮肤皱褶处要擦干。
海水与泳池水。有人有帮助，有人会加重，尤其是皮肤已有裂口时。不必因此不去海边——下水前先涂保湿，上岸后用清水冲洗并补涂保湿，观察一两次就知道自己属于哪一类。
灰尘。我曾有位病人只有脚踝长湿疹，怎么治都不好，后来才发现她的办公室在装修，灰尘整天沉在地面高度。如果你的湿疹分布很奇怪，请告诉我家里或工作环境有什么改变。潮湿气候也利于尘螨滋生，床单每周热水清洗有帮助。
冷气。室外潮湿、室内干燥，一天来回切换对皮肤屏障不利。别对着床吹，睡前一定要涂保湿。
日常化学品。香味重的沐浴露、抗菌洗剂、洗碗精（手部湿疹戴手套就能解决一大半）。