Few ingredients have stood the test of time quite like coal tar. This is especially true when managing chronic scalp conditions like psoriasis, eczema or persistent dandruff. Despite being a traditional remedy, it continues to earn its place in modern hair care. Coal tar shampoos and topical treatments can help soothe inflammation, reduce scaling and even improve the overall health of the scalp. It has also long been the beauty insider’s secret for treating hair loss and boosting growth. However, how much of this is fact versus legend? In this article, we explore what coal tar is. We look at the evidence for its scalp and hair benefits, and the best way to use it.
What is Coal Tar and How Does it Work?
This is a thick black substance that is actually a by-product from the carbonisation of coal. Despite being an industrial waste product, it has a surprisingly long and respected history in medicine going back centuries. Its therapeutic properties were first properly explored in the 19th century. It proved effective for treating chronic skin conditions like psoriasis and eczema. As such, it is especially useful for managing scaly, inflamed or irritated skin.
Its role in scalp health emerged not long after. This was especially true for conditions like scalp psoriasis and seborrhoeic dermatitis, which can lead to itching, flaking and hair shedding. Coal tar shampoos and topical treatments can help calm irritation, reduce build-up and improve overall scalp health. There is also growing interest in coal tar for treating hair loss and improving quality. Coal tar works on the scalp and hair through several key mechanisms:
- Slows skin cell turnover: Coal tar reduces the rate of skin cell production and shedding. This helps prevent the build-up of thick scaly patches on the scalp.
- Reduces inflammation: It possesses anti-inflammatory and antipruritic (anti-itch) properties. These effects can calm and soothe irritated or itchy scalps.
- Breaks down scale and build-up: Coal tar has mild keratolytic effects. This helps to loosen and remove the crusty layers of flaky skin that occur in conditions like psoriasis or seborrhoeic dermatitis.
What are the Benefits of Coal Tar for Scalp Health?
Coal tar is most popular as a treatment for chronic inflammatory scalp conditions. These include psoriasis, eczema, seborrhoeic dermatitis and stubborn dandruff. This is largely due to its anti-inflammatory and keratolytic effects. The main benefits of coal tar as a scalp treatment include:
- Scalp psoriasis: Coal tar helps to slow down the excessive production of skin cells, reduce inflammation and soften thick scaling. This not only relieves discomfort but also makes it easier to remove plaques. Coal tar shampoo is frequently recommended for mild to moderate scalp psoriasis. It is often a first-line option before progressing to stronger prescription treatments.
- Scalp eczema: Here coal tar helps to calm inflammation, reduce flaking and relieve itching. Whilst it does not cure eczema, regular use can help improve symptoms and reduce flare-ups, especially in more persistent cases.
- Seborrhoeic dermatitis (dandruff): Coal tar can be highly effective, especially in cases that are resistant to normal anti-dandruff shampoos. It works by slowing the rate of skin cell shedding, breaking down stubborn build-up and easing irritation. Other ingredients like ketoconazole target the underlying fungal cause, whilst salicylic acid exfoliates. Compared with these, coal tar offers broad anti-inflammatory action. This makes it useful for long-term scalp maintenance.
Can Coal Tar Really Treat Hair Loss and Stimulate Growth?
Coal tar is not a hair growth stimulant in the traditional sense. It does not directly trigger follicular activity or stimulate new growth like minoxidil or finasteride. However, it may indirectly support hair health by improving the overall condition of the scalp. It can also play a valuable supportive role in managing certain types of hair loss. This is particularly true where inflammation or chronic scalp conditions are contributing factors.
Issues such as scalp psoriasis, seborrhoeic dermatitis and chronic eczema can compromise scalp health. This can then lead to excess hair shedding and loss. In these cases, coal tar may help slow down hair loss by:
- Reducing inflammation: This is what weakens or damages hair follicles.
- Stopping itching: If persistent, itching can lead to scratching and mechanical hair loss.
- Clearing scale and build-up: These can block follicles or interfere with treatment absorption.
- Restoring a healthier scalp barrier: This creates a better foundation for hair retention.
Although coal tar will not regrow hair on its own, it can support the effectiveness of targeted treatments. It does this by optimising scalp health and reducing flare-ups that might otherwise hinder progress. It has also been shown to improve the condition of hair, making it appear fuller and glossier. There is even some evidence that using coal tar as a scalp treatment can help regrow hair in alopecia areata. However, this data is based on small studies and larger trials are needed to explore it further.
How Do You Use Coal Tar Shampoos and Treatments?
You can easily find coal tar in over-the-counter medicated shampoos. The standard guidance is to use them 2 to 3 times per week. However, this can vary depending on the severity of your symptoms and the concentration in the product. Here is how to get the most out of a coal tar shampoo:
- Apply to wet hair, concentrating on the scalp.
- Massage gently, working the product through for even coverage.
- Leave on for 5 to 10 minutes before rinsing thoroughly.
- Avoid contact with the eyes, and rinse immediately if irritation occurs.
Coal tar is also available in creams, ointments and gels for more persistent or localised scalp issues. Closely follow the manufacturer’s guidelines for these and avoid getting them on the face or the rest of the body. For stronger formulations or long-term use, you should discuss it with your medical provider to reduce risks and side effects.
Is Coal Tar Safe?
Coal tar has a long history of use in dermatology and is generally considered safe when used as directed. However, like any active ingredient, it is not suitable for everyone. Some people may experience irritation, particularly with prolonged use or if it is applied to broken or inflamed skin. If you have sensitive skin or a history of contact allergies, be cautious. It is sensible to carry out a patch test before using it more widely.
There are valid concerns about the carcinogenic potential of coal tar. Industrial workers with long-term exposure to it have increased rates of certain cancers. There are also some concerns that it may increase the risk of skin cancer in patients who undergo UVB therapy alongside coal tar ointments. However, the evidence is not conclusive. However, there is plenty of evidence that appropriate use of coal tar in dermatology is safe. Studies show it does not cause an increased risk of cancers. This is probably because the pharmaceutical-grade coal tar used in medicated shampoos and topical treatments is highly refined. At approved concentrations, these are considered safe for short to medium-term use. If you are considering using coal tar for your scalp and hair, here are a few things to keep in mind:
- Regulation: Coal tar treatments available in countries like the UK are approved for cosmetic or medicinal use and meet safety standards.
- Side effects: These may include skin irritation, increased sensitivity to sunlight and temporary staining (especially on light-coloured or grey hair).
- Precautions: Do not use during pregnancy, breastfeeding or if you are allergic to coal tar. Also avoid applying it to damaged or infected skin.
Ultimately, you may be unsure whether coal tar is right for your scalp or hair condition. If so, speak to a dermatologist or healthcare provider. In particular, seek medical help in advance if you are managing a chronic skin condition or using other treatments alongside it.
How Does Coal Tar Compare with Other Scalp Treatments?
As you can see, coal tar is a long-standing treatment for managing chronic scalp conditions. It is especially useful for those with inflammation and scaling. That said, it is not the only ingredient available. Depending on your specific concern and its severity, other treatments may be more appropriate instead of or alongside it. Here is how it compares against other popular scalp treatments:
- Ketoconazole: This antimicrobial ingredient is especially effective for seborrhoeic dermatitis and dandruff, which may be due to overgrowth of Malassezia yeast. It also has anti-inflammatory properties. Although coal tar offers broader anti-itch and anti-scaling benefits, ketoconazole is more targeted. However, it may be less effective for non-fungal conditions like psoriasis.
- Salicylic acid: This exfoliating agent is useful to soften and remove thick scaling like that seen in psoriasis. It works by dissolving the bonds between dead skin cells, helping to clear scale and improve the penetration of other treatments. Unlike coal tar, it does not have anti-inflammatory effects or help slow down skin cell turnover. As such, it is usually used in combination with other ingredients rather than as a standalone treatment.
- Topical corticosteroids: These powerful anti-inflammatories are useful for moderate to severe scalp inflammation, especially during acute flare-ups. They offer rapid relief but are not for long-term use due to potential side effects like skin thinning. In contrast, coal tar offers a milder, steroid-free option. It is safer for regular maintenance use, especially in milder or chronic cases.
Coal tar is the absolute opposite of a trendy ingredient. However, it has a staying power that is rare in modern scalp and hair care. For those struggling with persistent scalp issues or inflammation-related hair loss, coal tar may be a valuable addition. However, for the best results, always use it as part of a routine. Seek medical help if you are struggling with chronic scalp or hair conditions.
We know that hair loss is a deeply personal journey. This is why we created personalised hair loss and regrowth treatments through our online skin clinic. Our doctors create custom hair loss treatments using actives such as minoxidil, spironolactone and tretinoin where appropriate for each patient. We also treat skin concerns like acne, hyperpigmentation, melasma and signs of skin ageing with bespoke skincare treatments. You can book a video consultation or use our online consultation form to get started. The journey towards great hair starts here.
This article is intended for general informational purposes only and is not a substitute for medical advice, diagnosis or treatment. Always consult a qualified medical professional with any concerns about your skin or treatment options.
