Why does the left foot itch at night in 18-year-old adult?

Question

Hello doctor,

I am asking about my younger brother, who is 18. For the past few weeks, he has been complaining that his left foot becomes extremely itchy late at night, especially around the ankle and the top of the foot.

There are some dry patches and mild redness, but no obvious signs of infection.

While searching online, we came across the question, “Why is my left foot itching at night as an 18-year-old?” Some sources mentioned atopic dermatitis as a possible cause.

He does have a history of sensitive skin and seasonal allergies. Could atopic dermatitis appear only on one foot like this, or should we also consider a fungal infection or another skin problem?

Please help.

Answer 1

Hello,

Welcome to icliniq.com.

I understand your concern.

Night-time itching of the foot can occur due to several skin conditions. The symptoms you describe, such as dry patches, mild redness, and intense itching at night, can be seen in a few different conditions.

One of them is atopic dermatitis, especially since your brother already has a history of sensitive skin and seasonal allergies, which are commonly associated with this condition.

Although atopic dermatitis usually appears on areas such as the elbows, knees, neck, or ankles, it can sometimes appear in a limited area, particularly if that area becomes irritated by friction, sweat, or dry skin.

However, it is less common for eczema to affect only one foot for a prolonged period, so other conditions should also be considered.

One possible cause is a fungal infection, commonly known as athlete’s foot and medically called tinea pedis. This is one of the most frequent causes of itching on the feet and may lead to itching that worsens at night, dry or scaly skin, mild redness or peeling, and sometimes involvement between the toes.

Another possibility is contact or irritant dermatitis, which is a reaction to substances such as new footwear or shoe materials, socks or detergents used to wash them, or excess sweating inside shoes.

Many inflammatory skin conditions, including eczema, tend to itch more at night because the skin becomes drier during the night, there are fewer distractions so the itching is perceived more strongly, and body temperature and inflammatory signals increase slightly at night.

Some simple measures may help initially. Keeping the skin well moisturized, especially before bedtime, can reduce dryness. It may also help to avoid tight or synthetic footwear that traps sweat, wear clean cotton socks, keep the feet clean and dry, and avoid scratching because it can worsen inflammation.

If the itching persists for more than two to three weeks, spreads, develops scaling between the toes, or causes thickened skin, a proper examination is recommended.

In some cases, a doctor may need to rule out a fungal infection or dermatitis, as the treatment approach differs for each condition.

To guide you more accurately, it would be helpful to know whether there is scaling or peeling between the toes, whether the itching occurs every night or only occasionally, and whether he recently started using new shoes, socks, or detergents.

If possible, you may also share clear photos of the affected area. After reviewing them, it may be easier to determine whether this looks more like eczema, a fungal infection, or another skin condition and guide you on the appropriate treatment to relieve the night-time itching.

I hope this has helped you.

Please feel free to reach out to me again if you have further queries.

Thank you.