Should I treat a tender black lesion on the foot now in a 40‑year‑old woman with improving plantar inflammation who cannot see her primary care physician until next week?

Immediate Evaluation and Treatment of a Tender Black Spot on the Foot

You should initiate treatment now while awaiting the primary care appointment, focusing on protecting the lesion, monitoring for infection, and determining whether urgent evaluation is needed based on specific clinical features. 1

Immediate Assessment Required

Before deciding on treatment, you must determine the nature of this black spot by examining for these specific features:

Critical Red Flags Requiring Urgent/Emergency Care (Within 24-48 Hours)

• Signs of infection: Surrounding redness, warmth, swelling, purulent drainage, or systemic symptoms like fever 1
• Severe ischemia indicators: Cold foot, absent pulses, or pale/mottled skin 1
• Deep tissue involvement: Ability to probe to bone, extensive surrounding cellulitis, or visible necrotic tissue 1
• Diabetes with any foot lesion: Diabetic patients require immediate professional evaluation for any foot wound to prevent progression to ulceration 2, 3

Likely Benign Traumatic Lesion ("Black Heel")

If the black spot is:

• Located on the heel or posterolateral aspect 4
• Consists of grouped punctate hemorrhages (tiny dots of blood under the skin) 4
• Associated with recent athletic activity or trauma 4
• Not associated with pain beyond mild tenderness 4

This is likely "black heel" (calcaneal petechiae), a benign traumatic lesion that requires only observation and will self-heal. 4

Initial Home Management (If No Red Flags Present)

Wound Protection and Hygiene

• Wash the foot daily with soap and water, drying carefully, particularly between toes 5
• Avoid walking barefoot; wear cushioned, well-fitting footwear to protect the lesion 5
• Do NOT soak the foot in water, as this causes skin maceration and can worsen any open areas 5
• Apply a simple protective dressing if the skin is broken 1

What NOT to Do

• Do not use chemical corn removers, plasters, or aggressive debridement at home 6, 2
• Do not apply topical antibiotics routinely unless signs of infection develop 5
• Avoid tight or ill-fitting shoes that create friction over the area 1

Monitoring for Complications

Check Daily for These Warning Signs

• Increasing redness, warmth, or swelling around the lesion 5
• Development of purulent (pus) drainage 1
• Worsening pain or new throbbing sensation 1
• Red streaking extending up the foot or leg 1
• Fever or feeling systemically unwell 1

If any of these develop, seek medical attention immediately rather than waiting for the scheduled appointment. 1

When to Seek Earlier Medical Evaluation

Seek Care Before Next Week If:

• The lesion is not improving after 2 weeks of conservative care 5
• You have diabetes, peripheral vascular disease, or immunosuppression 2, 3
• The black spot is enlarging or new lesions appear 1
• You cannot determine if the skin is intact or if there is an open wound 1
• Pain is interfering with walking or daily activities 1

Special Considerations

For Diabetic Patients

Diabetic patients should NOT wait and require same-day or next-day evaluation by a healthcare professional for any foot lesion, even if it appears minor. 2, 3 Diabetic foot infections can progress rapidly to deep tissue involvement, abscess formation, or osteomyelitis, and peripheral neuropathy may mask the severity of the problem. 1, 3

Differential Diagnosis to Consider

While awaiting evaluation, be aware this could represent:

• Traumatic petechiae (most common in active individuals) 4
• Puncture wound with retained foreign body 7
• Early diabetic foot ulcer with overlying necrosis 1
• Ischemic lesion 1
• Rarely, melanoma or other malignancy 1

The primary care physician will need to examine the lesion directly, potentially pare it down to determine if it represents superficial hemorrhage versus deeper pathology, and assess vascular status. 1, 4

Summary Algorithm

1. Assess for red flags (infection, ischemia, diabetes, deep involvement) → If present, seek urgent care 1, 2
2. If no red flags: Protect with cushioned footwear, maintain hygiene, avoid trauma 5, 4
3. Monitor daily for signs of infection or worsening 5
4. Seek earlier care if not improving in 2 weeks or if complications develop 5
5. Keep scheduled appointment for definitive diagnosis and management 1