Compare · Ingredients

Coal Tar vs Salicylic Acid

Coal Tar: Helps reduce scaling and itching in psoriasis and some scalp products. Salicylic Acid: Helps unclog acne-prone skin; stronger products treat selected thickened skin lesions.

Research updated 2026-10-25

Five medicated scalp products on white, including Amazon Basics tar gel, T+Plus, MG217, RoyceDerm and Nizoral

Paula's Choice 2% BHA exfoliant, La Roche-Posay Effaclar cleanser and a CeraVe psoriasis cream pump

Which one?At a glance What it helps Diagrams Using both Strengths Results Safety How it works Products Questions

Which one is right for you?

Choose Coal Tar if…

Consider for scaly psoriasis or an appropriate scalp product if smell and staining are acceptable.

Thick, scaly psoriasis or scalp scale
Smell and staining are acceptable
Other scalp treatments haven’t helped

Choose Salicylic Acid if…

Choose for blackheads and clogged pores; use the strength labelled for that area.

Blackheads and clogged pores
Oily skin
Scalp scale or warts (with the right strength)

Often combined

Can you use both?

Often combined for scalp psoriasis: salicylic acid lifts scale so coal tar can reach the skin.

At a glance

● Coal Tar

● Salicylic Acid

Type

Anti-scaling medicine mixture

Beta hydroxy acid (BHA) and keratolytic

What it does

Helps reduce scaling and itching in psoriasis and some scalp products.

Helps unclog acne-prone skin; stronger products treat selected thickened skin lesions.

Best for

Psoriasis; Scalp Psoriasis; Dandruff

Acne; Blackheads; Warts; Scalp Psoriasis

Studied concentrations

1–5% crude coal tar preparations in older psoriasis trials; labels use different equivalents.

0.5–2% acne products differ from high-strength wart products and professional peels.

When to use

Morning or night, as directed by the finished product.

Start on a few evenings weekly; increase only if comfortable.

Time to results

Often 8–12 weeks in small cosmetic studies; results may be subtle

Often 8–12 weeks in small cosmetic studies; results may be subtle

Irritation

Can irritate, stain skin or fabrics, and increase sun sensitivity; follow the label.

May sting, peel or dry skin; avoid large areas, broken skin and known salicylate allergy without advice.

Sensitive skin

Choose a simple formula and test a small area first. Individual tolerance matters more than an ingredient’s reputation for being gentle.

Choose a simple formula and test a small area first. Avoid actively inflamed or broken skin unless the product is specifically directed for it.

Available

Prescription or cosmetic status depends on the active, formula and country; check the label.

Cosmetic or OTC products; some high-strength procedures are separate treatments.

What it helps

Compare uses by strength of evidence. Evidence level describes confidence in a benefit, not its size.

Evidence level

Coal Tar

Salicylic Acid

Moderate evidenceSome supportive research

Two thick, sharply bordered plaques on a knee on fair light skin. They are salmon-pink to red with loose silvery-white scale on top.

Psoriasis

Older controlled studies support some coal-tar preparations for plaque psoriasis.

Inflamed acne on light skin. The spots sit in a patch of pink, and the ring of redness around each one is easy to see. A few have a yellow-white head, and the skin between them is dry and flaking.

Acne

A guideline-supported option, especially for clogged pores.

dark keratin plugs in dilated pores on the nose and adjacent left cheek, with the face turned to the person’s right on light skin.

Blackheads

Helps loosen follicular plugs; it does not permanently change pore size.

A rough, dome-shaped wart on the side of a finger on fair skin. The bump is pinkish with a thin red ring at its base, and several tiny black dots are clearly visible in the thickened surface.

Warts

Labelled high-strength wart products are separate from facial acne products.

Limited evidenceEarly or small studies

Parted hair on fair scalp skin showing a raised salmon-pink plaque topped with dry silvery-white scale, with a sharply drawn border against normal skin.

Scalp Psoriasis

Can help scale in appropriate scalp products; the cited body trials are indirect.

A part line in straight light hair, seen from above, on pale skin. White-gray flakes sit along the part and the scalp beneath them looks pink.

Dandruff

Used in labelled scalp products; evidence varies by formula.

Parted hair on fair scalp skin showing a raised salmon-pink plaque topped with dry silvery-white scale, with a sharply drawn border against normal skin.

Scalp Psoriasis

Can help loosen scale in suitable products; it does not treat all inflammation.

Insufficient evidence

Salmon-pink patches with fine greasy yellowish scale in the crease beside the nose and through the eyebrow on fair skin, with soft edges that fade into normal skin.

Seborrheic Dermatitis

The reviewed sources do not establish this ingredient as a treatment for this concern.

Inflamed acne on light skin. The spots sit in a patch of pink, and the ring of redness around each one is easy to see. A few have a yellow-white head, and the skin between them is dry and flaking.

Acne

The reviewed sources do not establish this ingredient as a treatment for this concern.

AI-generated educational illustration of Perioral Dermatitis: 1. Perioral Dermatitis Header — Light Skin; Lighter skin. Not a clinical photograph.

Perioral Dermatitis

The reviewed sources do not establish this ingredient as a treatment for this concern.

Redness and fine superficial vessels across a light-skinned cheek and nose.

Rosacea

The reviewed sources do not establish this ingredient as a treatment for this concern.

Acne scarring on light skin. Small sharply cut pits and broad shallow dips across a cheek, several sitting inside faint flat pink marks, with no active spots.

Acne Scarring

The reviewed sources do not establish this ingredient as a treatment for this concern.

How it works

Coal Tar mechanism diagram. Acts on rapid cell buildup: Coal tar affects abnormal epidermal activity. Helps reduce scale and itch: Response depends on the condition and formula. — Open full-size diagram
Diagram explanation and sources
Acts on rapid cell buildup: Coal tar affects abnormal epidermal activity. Helps reduce scale and itch: Response depends on the condition and formula.
Schematic illustration; not a measurement of skin penetration. Effects vary with ingredient identity and formulation.
Source 1 · Source 2

Salicylic Acid mechanism diagram. Loosens outer skin cells: Salicylic acid promotes keratin shedding. Helps clear follicular plugs: Its acne role depends on strength and vehicle. — Open full-size diagram
Diagram explanation and sources
Loosens outer skin cells: Salicylic acid promotes keratin shedding. Helps clear follicular plugs: Its acne role depends on strength and vehicle.
Schematic illustration; not a measurement of skin penetration. Effects vary with ingredient identity and formulation.
Source 1 · Source 2 · Source 3 · Source 4

Using both in one routine

Built from where each one usually sits in a routine. Introduce one at a time.

Morning

Step 1

Salicylic AcidMorning or night

Step 2

Moisturizer

Step 3

Sunscreen

Step 4

Coal TarAs directed

Night

Step 1

Salicylic AcidMorning or night

Step 2

Moisturizer

Step 3

Coal TarAs directed

Strengths and forms

Concentrations

U.S. dandruff, seborrheic dermatitis and psoriasis products use 0.5–5% coal tar under specified labeling conditions. The percentage of a coal-tar solution is not necessarily the percentage of actual coal tar.

0.5–5%

U.S. labeled active range

A range for qualifying medicated products. Read the actual coal-tar equivalent when the label also names a coal-tar solution or extract.

Choosing a strength: Match shampoo, cream or ointment to the condition and body area. Look for the active concentration rather than comparing solution percentages.

Higher strengths: A larger solution percentage can be misleading. Stronger preparations may be less acceptable because of irritation, odor or staining.

Formula matters: Crude coal tar, coal-tar solutions and refined preparations differ. Their printed numbers should not be treated as identical doses.

The percentage depends on the job: 0.5–2% for OTC acne care, 20–30% in studied office peels, and up to 40% in labeled wart patches. These are different treatments, not steps to work through.

0.5–2%

1.8–3%

5–17%

20–30%

12–40%

Everyday acne care

For blackheads, whiteheads and acne in washes or leave-on products. Follow the product label; dryness or stinging can limit use.

Scalp scale

In labeled treatments for dandruff, seborrheic dermatitis or psoriasis. Helps loosen scale; follow the scalp product’s directions.

Liquid wart removers

For common or plantar warts; 17% is one labeled option. Apply only to the wart, avoiding surrounding healthy skin. Not for facial acne.

Professional office peels

A studied range for clinician-applied peels, including acne treatments. Not for routine home use. Formula, layers and contact time affect the burn risk.

Wart patches and plasters

For common or plantar warts, depending on the label; 40% is a labeled option. Treat the wart only. These are not facial skincare products.

Choosing a strength: Choose for the diagnosis, body area and product type. Facial acne care, scalp products, wart treatments and office peels are not interchangeable.

Higher strengths: High-strength peels can cause burns, scarring and lasting skin-color changes. Wart removers are not for facial or genital warts, irritated or infected skin. Do not self-treat warts with these products if you have diabetes or poor circulation.

Formula matters: The percentage alone does not show how deeply a treatment acts. The base formula, contact time, number of peel layers and whether the product is washed off all matter. Follow the specific label or clinician’s directions.

Forms

Shampoo · Ointment · Bath solution

Wash · Toner · Wart pads

When you’ll see results

Approximate windows, not promises.

● Coal Tar

● Salicylic Acid

First few weeks

First few weeksAssess tolerance and texture; immediate softness can come from the base formula.

First few weeksAssess tolerance and texture; immediate softness can come from the base formula.

4–8 weeks

4–8 weeksSubtle changes may appear in some tested products; evidence varies.

4–8 weeksSubtle changes may appear in some tested products; evidence varies.

8–12 weeks

8–12 weeksCompare photographs in the same lighting and reassess benefit.

8–12 weeksCompare photographs in the same lighting and reassess benefit.

3–6 months

3–6 monthsPhotoaging trials often need several months; expect modest rather than dramatic change.

3–6 monthsPhotoaging trials often need several months; expect modest rather than dramatic change.

6–12 months

6–12 monthsLong-term evidence is limited for many cosmetic actives; continue only if useful.

6–12 monthsLong-term evidence is limited for many cosmetic actives; continue only if useful.

Safety and sensitive skin

Common reactions

Can irritate, stain skin or fabrics, and increase sun sensitivity; follow the label.

May sting, peel or dry skin; avoid large areas, broken skin and known salicylate allergy without advice.

When to stop

Stop for persistent burning, swelling, blistering or a new rash. Seek urgent care for breathing difficulty or a severe allergic reaction.

Stop for persistent burning, swelling, blistering or a new rash. Seek urgent care for breathing difficulty or a severe allergic reaction.

Sensitive or inflamed skin

Choose a simple formula and test a small area first. Individual tolerance matters more than an ingredient’s reputation for being gentle.

Choose a simple formula and test a small area first. Avoid actively inflamed or broken skin unless the product is specifically directed for it.

Important limits

Do not use a cosmetic product as a substitute for diagnosis of an unexplained, changing or persistent skin problem.

Do not use a cosmetic product as a substitute for diagnosis of an unexplained, changing or persistent skin problem.

Pregnancy

Coal tar is usually avoided in pregnancy and while breastfeeding; ask the clinician managing your pregnancy about alternatives.

Over-the-counter strengths on the face are generally considered acceptable, but confirm with the doctor managing your pregnancy. High-strength peels and large body areas are avoided.

How it works

In the skin

On the skin. The finished product delivers coal tar in a particular vehicle.

Entering skin. No single molecular mass. The 500 Da guideline cannot be applied to this whole ingredient family or mixture.

Conversion. No activation step is established as necessary for its intended topical role.

Skin response. A complex mixture affects abnormal skin-cell turnover and inflammation; no single active molecule defines it.

Additional effects. Proposed pathways do not establish a measured depth of delivery or clinical benefit beyond the studies cited.

On the skin. The finished product delivers salicylic acid in a particular vehicle.

Entering skin. Below the 500 Da guideline; delivery still depends on the formula, solubility, stability and skin condition. Size does not prove effectiveness or penetration depth.

Conversion. No activation step is established as necessary for its intended topical role.

Skin response. Promotes shedding of outer cells and helps clear follicular plugs; concentration and vehicle set its use.

Additional effects. Proposed pathways do not establish a measured depth of delivery or clinical benefit beyond the studies cited.

Getting in

No single molecular mass. The 500 Da guideline cannot be applied to this whole ingredient family or mixture.

Below the 500 Da guideline; delivery still depends on the formula, solubility, stability and skin condition. Size does not prove effectiveness or penetration depth.

Product examples

Coal Tar

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.
MG217 Psoriasis Gel — Coal tar 2% in an alcohol gel that washes out of hair. Flammable, and it contains fragrance.
Psoriasin Deep Moisturizing Ointment — Coal tar 2% in petrolatum. A real psoriasis drug, and the label says adults only.

Salicylic Acid

CeraVe Cleanser for Psoriasis Treatment with Salicylic Acid
La Roche-Posay Effaclar A.Z. Salicylic Acid Acne Medication
Aveeno Clear Complexion Daily Moisturizer Salicylic Acid

Common questions

Coal Tar:What should I choose coal tar for?

Consider for scaly psoriasis or an appropriate scalp product if smell and staining are acceptable.

Coal Tar:How strong is the evidence?

Small older trials studied particular tar preparations. Strengths expressed as crude tar and coal-tar solution are not directly interchangeable, and evidence cannot be generalized to every shampoo.

Salicylic Acid:What should I choose salicylic acid for?

Choose for blackheads and clogged pores; use the strength labelled for that area.

Salicylic Acid:How strong is the evidence?

Acne guidelines give a conditional recommendation. High-strength wart treatments and 30% peels are distinct interventions; their evidence cannot justify high-strength facial home use.

Sources

Sources and further reading

Dermapedia on YouTube