Coal tar has been used to treat psoriasis for many years, particularly scalp psoriasis. Creams, lotions, scalp applications, shampoos and bath additives are available from your pharmacy or GP.
Coal tar is a thick, heavy oil that has been used to treat psoriasis for hundreds of years. It is thought to have anti-inflammatory and anti-scaling properties that are useful in treating plaque psoriasis. The treatments are topical (applied to skin) and come in lotion, cream, ointment, shampoo, and bath additive forms.
Traditional coal tar treatments were made up in a hospital pharmacy and were smelly, messy, and difficult to use. In contrast, most modern coal tar applications are more cosmetically acceptable. Coal tar treatments are shampoos, lotions, creams or ointments and are rubbed in to the plaques of psoriasis. These treatments are referred to as ‘topical treatments’.
Many people with psoriasis will try a coal tar treatment at some point. They are most commonly used for scalp psoriasis, although some people may also use coal tar to treat plaque psoriasis on other parts of the body too.
Some coal tar treatments can be bought ‘over the counter’ (without a prescription) from a pharmacy or supermarket. They can also be prescribed by your doctor, although it is recommended that other topical treatments such as vitamin Ds and topical steroids are tried in various strengths and combinations first. This is because research has found that vitamin D or topical steroid treatments are more likely to be more effective at treating psoriasis. However, this does not mean that coal tar treatments do not work for some people – they can be an effective and useful treatment for psoriasis, and are more suitable for longer-term use than some other topical treatments.
It is recommended that a review appointment is arranged four weeks after starting any new topical treatment (two weeks for children), so that your doctor can assess what the results of the treatment are so far, and to check if you need any help with using the treatment.
As with all topical treatments, it may take a number of weeks of use for a coal tar treatment to become fully effective.
Contact between coal tar products and non-psoriasis skin is not usually harmful, and so it can be used for widespread or small plaque psoriasis. Not all coal tar treatments are the same, and it is important to check with your doctor or pharmacist that the topical treatment you have been prescribed is suitable for all the body areas you need to use it in.
Coal tar treatments can sometimes cause skin irritation, and should not be used on inflamed or broken skin, near to the eyes or on genital areas. Depending on the particular product used, it may stain clothes and other items that come into contact with the treatment. Some coal tar treatments are thought to increase a person’s sensitivity to sunlight, so unnecessary exposure to the sun (including the use of sunbeds) should be avoided.
For information on the different types of coal tar treatments available to treat psoriasis, take a look at our coal tar information sheet.