Australia Weather News

Darwin broke an unwanted record on Tuesday night when the overnight minimum temperature reached a balmy 30C degrees.

This surpassed the previous maximum of 29.7C, making it the city's hottest night on record, while other weather records in the Top End tumbled last week.

Living in the tropics at this time of year means a sheen of sweat can accompany your every step outside of air conditioning, so if your skin's looking a little worse for wear, you're not alone.

The unsavoury conditions often joked about — fungal and bacterial infections, tinea, abscesses — are a day-to-day part of a dermatologist Dev Tilakaratne's work in the tropics

Understanding why comes back to the skin's role as a barrier to the environment, he told ABC Radio Darwin's Georgia Hitch.

"At the extreme — so extreme heat, extreme cold — our skin is there to facilitate and help us adjust to that," he said.

"The most basic mechanism that we have is that we get increased blood flow to the skin during times of heat.

"So you can imagine, with so much blood coming to our skin, it's able to radiate that heat out, dissipate it, and allow us to stay cooler."

Unfortunately, he said, sometimes we can more or less wear out that mechanism — enter sweat.

"There's only so much that that can do for us, so the sweating helps as well to kind of evaporate and cool that way."

"But unfortunately sometimes those processes go awry, and that's when disease can result."

Acne flaring up? This could be why

In sweaty conditions, Dr Tilakaratne said, increased oil production could cause your skin to become a little macerated.

"[The skin] just kind of retains a bit too much moisture and the integrity of the surface layer of the skin or the epidermis starts to suffer a little," he said.

"Basically, the nasty bugs take advantage of that."

He said tropical skin conditions could have any number of triggers — sweat, heat, environmental factors or predispositions — that needed to be examined on a case-by-case basis.

Urticaria (hives), Darier's disease (characterised by scaly, raised blemishes) and rosacea (skin inflammation) are among those that tended to be exacerbated by intense heat.

"And acne itself is probably a really big one up here," Dr Tilakaratne said.

"A lot of the time acne is just limited to the face, but in the heat we tend to see it then developing on the shoulders, back and even the chest.

"That is largely just a function of heat."

Dr Tilakaratne emphasised this is generic advice, but heat does keep him busy because of the way it interacts with the skin.

"When we think about where things happen on the body, in terms of tropical infection, it tends to be in skin folds — areas where the body temperature is a little higher," he said.

"The epidermis — the surface layer of the skin — is getting a little eroded."

An extra layer of clothing may help

While the common local coping strategy is to wear as little clothing as possible, Dr Tilakaratne said there were some instances when adding a second layer might help.

Lighter, more breathable fabrics — made of natural fibres rather than synthetic ones — will allow your skin to breathe and keep a lid on sweat in the first place.

"At the same time, depending on how much heat people are being exposed to, it can also be worthwhile wearing an underlayer of a very light cotton or a bamboo/cotton style of clothing," he said.

"The reason for that is that underlayer can then wick away that sweat as it forms on your body.

"If that can be changed a couple of times a day, then it means there's no real significant period of time where the sweat is just right up against the body, and there's no way for the sweat to kind of get congested and start back flowing down the sweat glands, which is when we start to see problems."

It's not all bad news

At the other end of the scale, the tropical conditions can actually help some skin conditions.

Dr Tilakaratne said eczema was much more burdensome down south than for his clients in the Territory.

This is largely because the humidity moisturises the skin and protects eczema suffers to some degree.

"There are a lot of people who are really plagued by eczema, especially atopic eczema, in the southern states who have moved to tropical climates deliberately and who have fared very well," he said.

"There is obviously a tipping point though," he added, saying that heat could exacerbate itchy conditions.

Above all, he stressed the exact cause of some conditions required thorough investigation to identify.

"Day-to-day, dealing with skin problems is like detective work, really.

"There are many factors that you have to take into consideration, and it's not like there is a standard formula or a tree diagram you can follow.

"You really have to piece together a lot of different parts of the situation."