"Fish Eyes" on Your Foot? They May Not Be Calluses—Here's What You Should Know 👣

Have you ever noticed a thick, painful spot on the bottom of your foot that looks like a callus but doesn't behave like one? In many countries, people refer to these lesions as "fish eyes" because of their round appearance with a rough center. Medically, they are often plantar warts, which are quite different from ordinary calluses.

Although plantar warts and calluses can look similar, they have different causes, symptoms, and treatments. Knowing the difference is important because treating a wart like a callus may not solve the problem—and in some cases, could even make it worse.

Let's explore how to tell them apart and what you can do if you think you have one.

What Is a Plantar Wart?

A plantar wart is a growth on the sole of the foot caused by infection with certain types of the human papillomavirus (HPV).

The virus enters the skin through tiny cuts or abrasions, especially in warm, moist environments such as:

• Public swimming pools
• Locker rooms
• Gym showers
• Shared changing rooms

Not everyone exposed to HPV develops a wart. Your immune system plays a major role in determining whether the virus causes an infection.

How Is a Plantar Wart Different from a Callus?

Although they may appear similar at first glance, there are several important differences.

Plantar Wart

Usually:

• Has a rough, grainy surface
• Interrupts the normal skin lines
• May contain tiny black dots (small clotted blood vessels)
• Can be painful when squeezed from the sides
• May occur alone or in clusters (mosaic warts)

Callus

Usually:

• Forms because of repeated pressure or friction
• Has smooth, thickened skin
• Preserves normal skin lines
• Lacks black dots
• Is generally painful when direct pressure is applied from above

A healthcare professional, such as a podiatrist or dermatologist, can usually distinguish between the two during an examination.

Common Symptoms of Plantar Warts

People with plantar warts may experience:

• A rough bump on the sole
• Pain while walking
• Tenderness when standing
• A feeling like stepping on a pebble
• Thickened skin over the wart
• Small black pinpoint spots

Because body weight pushes the wart inward, plantar warts often grow beneath the surface rather than protruding outward.

How Do You Get Plantar Warts?

HPV spreads through direct contact.

Risk factors include:

• Walking barefoot in public showers
• Using shared pool areas
• Small cuts on the feet
• Excessive sweating
• Weakened immune function

It's important to remember that HPV is common, and developing a wart does not mean someone has poor hygiene.

Can Plantar Warts Go Away on Their Own?

Yes.

Many plantar warts eventually disappear as the immune system clears the virus.

However, this may take:

• Several months
• One to two years
• Occasionally even longer

Because they can be painful and contagious, many people choose to seek treatment rather than waiting.

Treatment Options

Treatment depends on:

• Size of the wart
• Number of warts
• Pain level
• Overall health

Common treatments include:

Salicylic Acid

Over-the-counter salicylic acid products gradually remove layers of the wart.

For best results:

• Soak the foot in warm water.
• Gently file away dead skin (using a tool reserved only for the wart).
• Apply the medication as directed.
• Repeat consistently for several weeks.

Cryotherapy

A healthcare professional may freeze the wart with liquid nitrogen.

Multiple treatments are often needed.

Prescription Treatments

If home treatments don't work, your healthcare provider may recommend:

• Stronger topical medications
• Immunotherapy
• Laser therapy
• Minor surgical procedures in selected cases

The best treatment varies from person to person.

Avoid These Common Mistakes

Do not:

❌ Cut the wart yourself with a knife or razor.

❌ Pick at the wart.

❌ Share nail files, pumice stones, or towels.

❌ Walk barefoot in public locker rooms if you have an active wart.

These practices may increase the risk of infection or spreading the virus.

How to Reduce Your Risk

Simple preventive habits include:

✔ Wear flip-flops in public showers and pool areas.

✔ Keep your feet clean and dry.

✔ Avoid sharing footwear or towels.

✔ Cover existing warts with a waterproof bandage when appropriate.

✔ Treat excessive sweating if recommended by your healthcare provider.

✔ Inspect your feet regularly, especially if you have diabetes.

When Should You See a Doctor?

Seek medical advice if:

• The growth is very painful.
• You're unsure whether it's a wart or something else.
• The lesion changes rapidly in size or appearance.
• It bleeds frequently.
• Home treatment hasn't helped after several weeks.
• You have diabetes, poor circulation, or a weakened immune system.

People with diabetes or reduced sensation in their feet should not attempt to remove foot lesions themselves, as even small injuries can lead to serious complications.

Common Myths About Plantar Warts

Myth: Every thick spot on the foot is a callus.

Reality: Some thickened areas are plantar warts, while others may be calluses, corns, cysts, or other skin conditions. Proper diagnosis is important.

Myth: Plantar warts have roots that must be pulled out.

Reality: Warts do not have roots. The dark spots seen inside are tiny clotted blood vessels, not roots.

Myth: Only children get plantar warts.

Reality: Although they're more common in children and teenagers, adults can also develop plantar warts.

The Bottom Line

A painful, thickened spot on the bottom of your foot isn't always a callus. Plantar warts ("fish eyes") are caused by certain types of HPV and require different treatment than friction-related calluses. Features such as tiny black dots, interruption of normal skin lines, and pain when the lesion is squeezed from the sides can suggest a plantar wart, but only a healthcare professional can make a definitive diagnosis.

Most plantar warts are benign and often resolve over time, but treatment can relieve discomfort and reduce the risk of spreading the virus. If you're unsure what you're dealing with—or if the lesion is painful, persistent, or changing—consult a podiatrist or dermatologist for an accurate evaluation and appropriate care.