Black soap may offer some benefits for eczema, but the evidence is limited and the results are mixed. In the only published survey measuring satisfaction among eczema users, all seven participants reported being at least “somewhat satisfied,” but none rated themselves “very satisfied.” Researchers noted that black soap appeared least effective for eczema compared to other skin conditions, likely because of its drying potential. That’s a meaningful concern when your skin barrier is already compromised.
What Black Soap Actually Contains
Traditional African black soap is made from plant-based ingredients: shea butter, palm kernel oil, and ash from burned plantain skins or cocoa pods. The ash serves as a natural lye that turns the fats into soap. Some formulations include additions like guava leaf, which has mild antibacterial and antioxidant properties. The shea butter content can be significant, up to 50% in some recipes, which gives the soap more moisturizing potential than a standard bar soap.
These ingredients do contain vitamins A and E, both of which support skin repair. And lab studies confirm that traditional black soap has antimicrobial activity against Staphylococcal bacteria. That’s relevant because Staph aureus colonizes the skin in the majority of eczema patients and is a known trigger for flares. In theory, a soap that reduces bacterial load while delivering some moisture could be helpful.
Why It Can Backfire on Eczema Skin
The problem is pH. Healthy skin sits at a slightly acidic pH of around 4.5 to 5.5, and eczema skin is especially sensitive to disruptions in that acid mantle. Traditional black soap tests alkaline, with pH values ranging from 8.7 to 9.7 depending on the formulation. That’s a significant gap. Alkaline cleansers strip the natural oils from the outermost layer of skin, which is exactly the layer that’s already damaged in eczema. The result can be increased dryness, stinging, or irritation rather than relief.
A survey published in The Journal of Clinical and Aesthetic Dermatology found that only 7% of black soap users were using it for eczema in the first place. Among those who did, satisfaction was notably lower than for conditions like acne or dark spots. The researchers specifically flagged the soap’s potential drying effect as a likely explanation. When your skin can’t hold moisture well, a cleanser that strips additional oils away works against you.
How to Try It Safely
If you want to test black soap on eczema-prone skin, a cautious approach matters. Start with a patch test on a small area of your body, ideally somewhere that isn’t actively flaring. Wait 24 to 48 hours and watch for redness, tightness, or stinging.
If that goes well, use it sparingly. Lather the soap between your hands first rather than rubbing the bar directly on your skin, which reduces both friction and the concentration of soap hitting your skin at once. Rinse thoroughly with lukewarm water (hot water worsens eczema dryness) and pat dry rather than rubbing with a towel. A little goes a long way. Using too much is one of the most common reasons people experience irritation.
The most important step comes after washing: apply a fragrance-free moisturizer immediately while your skin is still slightly damp. This locks in hydration and helps counteract whatever moisture the soap may have pulled out. Without this step, even a gentle cleanser can leave eczema skin worse off.
Authentic vs. Mass-Produced Black Soap
Not all products labeled “African black soap” are the same. Authentic black soap is made with plant ash as the lye source and has an uneven, brown-to-dark-brown color with a rough texture. Mass-produced versions sometimes use synthetic lye bases, add iron oxide pigments to create a uniform jet-black appearance, and include fragrances or dyes that can trigger eczema flares on their own.
Check the ingredient list. If you see terms like “fragrance,” “iron oxides,” or a long list of synthetic chemicals, the product is likely a commercial imitation. Authentic black soap typically has a short, recognizable ingredient list: shea butter, palm kernel oil, cocoa pod ash or plantain ash, and water. For eczema-prone skin, fewer ingredients means fewer potential irritants. If a brand causes redness or irritation, switching to a different maker with a simpler formulation is worth trying before giving up on black soap entirely.
The Bigger Picture for Eczema Cleansing
Dermatologists generally recommend soap-free or syndetic cleansers for eczema because they can be formulated at a skin-friendly pH. Black soap, even the best traditional version, is still soap with an alkaline pH. That doesn’t make it useless, but it does mean it’s working against one of the core principles of eczema skin care: protecting the acid mantle.
Some people with mild eczema find that the shea butter content and antimicrobial properties offer enough benefit to outweigh the pH issue, especially if they moisturize immediately afterward. Others, particularly those with moderate-to-severe eczema or active flares, find it too drying. The survey data reflects this split: nobody reported being outright dissatisfied, but nobody was thrilled either. If your eczema is well-controlled and you’re drawn to a more natural cleanser, black soap is reasonable to try. If your skin is actively inflamed or cracked, it’s likely to cause more irritation than relief.