What are the risks of using a black salve to draw out pus from a skin lesion and what is the recommended treatment instead?

Black Salve: A Dangerous Escharotic Agent That Should Never Be Used

Black salve is a toxic, unregulated escharotic product containing bloodroot (sanguinarine) or other caustic substances that causes indiscriminate tissue destruction, severe scarring, and can mask underlying malignancies—it should never be used for any skin condition, and patients presenting with purulent lesions should receive proper medical treatment with incision and drainage plus antibiotics when indicated. 1, 2, 3

What Black Salve Actually Does

Black salve does not selectively "draw out" infection or abnormal tissue—instead, it causes uncontrolled chemical burns that destroy both healthy and diseased tissue indiscriminately. 1, 3, 4

• The product contains escharotic agents (typically sanguinarine from bloodroot or zinc chloride) that create full-thickness tissue necrosis, resulting in black eschars, ulceration, and permanent scarring. 1, 2, 4
• Patients experience severe pain during application, and the resulting wounds frequently become secondarily infected with purulent drainage. 1, 2
• The tissue destruction can extend deep into dermis and subcutaneous tissue, causing complications including enterocutaneous fistulas when applied to abdominal wall lesions. 2

Documented Harms and Complications

The medical literature documents serious complications from black salve use:

• Masking of malignancies: Black salve destroys superficial tumor tissue while leaving deeper malignant cells intact, creating false reassurance and delaying definitive cancer treatment. 2, 4
• Severe scarring and deformity: Application causes concave scars, keloid formation, and in vaginal/cervical use, complete stenosis requiring surgical correction. 1, 5, 4
• Secondary infections: The necrotic tissue becomes a nidus for bacterial infection requiring systemic antibiotics. 1
• Reactive stromal atypia: Histopathological examination shows features that can mimic malignancy, complicating subsequent diagnosis. 4

Proper Treatment of Purulent Skin Lesions

For Simple Abscesses and Infected Cysts

Incision and drainage is the definitive treatment—antibiotics are secondary and often unnecessary. 6, 7, 8

• Perform adequate incision, thorough evacuation of pus, and probe the cavity to break up all loculations. 6, 7, 8
• Cover with dry dressing; packing or primary closure is usually unnecessary. 6
• Antibiotics are NOT needed unless: fever ≥38.5°C, heart rate >110 bpm, erythema extending >5 cm from margins, multiple lesions, extensive cellulitis, or immunocompromised host. 7, 8

For Cellulitis (Diffuse Spreading Infection Without Pus)

Antibiotics are the primary treatment—do NOT perform incision and drainage as there is no pus collection. 7

• Use agents active against streptococci: cephalosporin, penicillin, or clindamycin for typical cases. 7
• Add MRSA coverage (vancomycin, linezolid, daptomycin, or oral trimethoprim-sulfamethoxazole/doxycycline/clindamycin) if risk factors present or severe infection. 6, 7
• Treat for 5-6 days for uncomplicated cases; extend only if not improving. 7

For Carbuncles (Coalescent Follicular Abscesses)

Incision and drainage is mandatory—systemic antibiotics are usually unnecessary unless fever or extensive cellulitis present. 6, 7

• Thoroughly evacuate pus from all involved follicles and break up loculations. 6, 7
• Add antibiotics only if systemic signs present or extensive surrounding cellulitis. 6, 7

Critical Clinical Pitfall

When patients present with black, necrotic skin lesions after using "herbal remedies" or "natural cancer cures," always suspect black salve use. 1, 2, 3

• Directly ask about internet-purchased topical treatments, as patients may not volunteer this information. 2, 3
• The black eschar mimics melanoma clinically and requires biopsy to rule out underlying malignancy. 2, 4
• Treat secondary infection with appropriate antibiotics and wound care, but biopsy is essential to exclude masked cancer. 1, 4
• Document the use of unregulated products in the medical record and counsel patients about the dangers of self-treatment. 1, 3

Patient Counseling Points

• Black salve is not FDA-approved and has no proven anticancer or antimicrobial properties. 3
• Products purchased online are unregulated with variable composition and no quality control. 1, 3
• The apparent "drawing out" of tissue is actually indiscriminate chemical destruction, not selective removal of diseased tissue. 3, 4
• Proper medical treatment (incision and drainage for abscesses, antibiotics for cellulitis) is safer, more effective, and prevents permanent scarring. 6, 7, 8