PRODUCT REVIEW
Soap Works Coal Tar Bar Soap
Coal tar works for psoriasis. This bar will not say how much is in it, and it is alkaline soap perfumed with essential oils, sold for eczema.
Key facts
Soap Works Coal Tar Bar Soap at a glance.
Coal tar (percentage not disclosed)
Key active
Bar soap
Texture
$3–$5
Approximate price
3.88 oz
Size
$2.30
Price
Cleanser
Type
What is it?
Top things to know about Soap Works Coal Tar Bar Soap
- Soap Works Coal Tar Bar Soap is a black bar containing coal tar extract, made in Canada, around $3 to $5. It is a medicated wash, not a leave-on treatment, so the tar sits on your skin only until you rinse it off.
- The label names coal tar extract as the active but never says how much, and a US drug label would have to. The base is sodium tallowate and sodium cocoate, which makes it true soap, and true soap is alkaline. It is colored with charcoal and iron oxide, scented with eucalyptus, geranium and rosemary oil, and it leaves skin squeaky.
It will not tell you how much coal tar is in it, and a US drug label would have to. Without a number you cannot know whether the dose works. It is also true soap, so alkaline and stripping, and perfumed with essential oils. Use a coal tar ointment that states its strength.
— Dr. Schwarz
Skin fit
Is it right for your skin?
Psoriasis
Psoriasis is skin cells made faster than they can shed, so plaques build up. Coal tar slows that overproduction and calms the inflammation behind it, and psoriasis guidelines rate the evidence highly. A wash-off bar is the weakest way to deliver it, and this one does not state its strength.
Scalp Psoriasis
Tar is easier to justify on the scalp, where a leave-on cream is unpleasant in hair. Lather the bar in and leave it a minute before rinsing. A tar shampoo with a stated percentage is still better.
Seborrheic Dermatitis
Coal tar slows the turnover behind the flaking and calms the inflammation, which is why tar shampoos have treated dandruff for decades. Weigh that against the alkaline base, working against a barrier that is already irritated.
Eczema
Steer clear. Eczema-prone skin already has a weak barrier, and alkaline soap raises skin pH, which switches on enzymes that break down the fats holding the outer layer together. Three added essential oils make that worse.
Texture
What it feels like on skin.
Wash
A hard black bar of true soap. It lathers freely, rinses clean, and leaves skin squeaky and tight. That tight feeling is the alkalinity. Skin sits at about pH 5 and this bar is around pH 9 to 10, so it strips the surface fats and skin takes hours to recover. Under the eucalyptus, geranium and rosemary oils it smells strongly of tar. Coal tar stains. Expect marks on light towels, bedding and grout.
Alternatives
If this isn’t the right product for you
MG217 Psoriasis Ointment
Coal tar 2% at a stated strength, in a fragrance-free petrolatum base. Greasy, it stains, and it raises sun sensitivity for a day.
Psoriasin Deep Moisturizing Ointment
Coal tar 2% declared on the label, three inactive ingredients, no added fragrance. Its label is written for healthy adults.
MG217 Psoriasis Gel
For the scalp, a coal tar 2% gel that washes out of hair. It contains fragrance and alcohol, and leaves skin sun-sensitive for about 24 hours.
Ingredients · Interactive
What’s in it, and where each ingredient works.
Full ingredient list · 8 ingredients, in label order. Click one.
A small humectant. It moves into the outer layer of skin and holds water there.
How to use it
How to use it.
How to apply it
- NextFollow with a plain, fragrance-free moisturizer while skin is still damp. Not optional with a soap this alkaline.
- CarefulCoal tar makes skin more sensitive to sunlight, so cover treated areas or use sunscreen. Stop if the skin stings, burns or breaks out in small bumps around the hair follicles.
What to expect
- What to expectCoal tar works slowly. Trials put it level with modern psoriasis treatments by around twelve weeks. With no stated strength, you cannot know whether you are getting a working dose.
Questions
Common questions.
How much coal tar is in Soap Works Coal Tar Bar Soap?
It does not say, only "coal tar extract." You cannot judge the dose or compare it.
Is Soap Works Coal Tar Bar Soap good for eczema?
Probably not. Alkaline soap and added fragrance both worsen a compromised barrier.
Does Soap Works Coal Tar Bar Soap treat ringworm?
No. Coal tar is not an antifungal.
Is the coal tar in Soap Works Coal Tar Bar Soap dangerous?
The cancer fear is largely misplaced for medicated use. The bigger issues are smell, staining and sun sensitivity.
Is Soap Works Coal Tar Bar Soap fragrance-free?
No. Eucalyptus, geranium and rosemary essential oils.
Should I moisturize after using Soap Works Coal Tar Bar Soap?
Yes. A plain, fragrance-free moisturizer, right after.
References
Sources.
- 1. Coal tar induces AHR-dependent skin barrier repair in atopic dermatitis (https://www.jci.org/articles/view/65642) — Establishes the mechanism claim: coal tar activates the aryl hydrocarbon receptor (AHR), restores filaggrin barrier protein, and dampens inflammatory (Th2) signalling; this is the research that led to Vtama. Link
- 2. Vtama Is a Natural AhR Agonist that Resolves Skin Inflammation (https://pubmed.ncbi.nlm.nih.gov/28595996/) — Backs the claim that Vtama works the same way as coal tar by acting as an aryl hydrocarbon receptor agonist to resolve skin inflammation. Link
- 3. Vtama cream FDA prescribing information (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=9309d20f-8cd4-4c96-93fa-7f730e83c7ab) — Confirms Vtama is an FDA-approved prescription drug and an aryl hydrocarbon receptor (AhR) agonist, the same receptor coal tar activates. Link
- 4. No increased risk of cancer after coal tar treatment in patients with psoriasis or eczema (https://pubmed.ncbi.nlm.nih.gov/20016499/) — Supports the safety claim that the cancer fear is largely misplaced: this cohort study found no increased cancer risk after coal tar treatment. Link
- 5. Joint AAD-NPF Guidelines of care for the management and treatment of psoriasis with topical therapy (https://pubmed.ncbi.nlm.nih.gov/32738429/) — Backs the claim that the American Academy of Dermatology's psoriasis guidelines recognise and recommend coal tar as a topical therapy for psoriasis. Link