Coal tar with zinc oxide

How it works

Coal tar provides anti-inflammatory, antiscaling and antipruritic effects on the skin, while zinc oxide acts as a mild astringent and protective barrier that soothes irritation and helps shield the skin.

Prescribing in practice

• Coal tar increases sensitivity to ultraviolet light, so treated skin should be protected from sunlight and caution applied if phototherapy is used.
• Avoid application to broken, infected or acutely inflamed skin, where tar may cause irritation or folliculitis.
• The preparation stains skin, hair, clothing and bedding and has a tar odour.

Monitoring

No laboratory monitoring is required; review the skin clinically for irritation and response to treatment.

Counselling the patient

• Apply as directed; expect staining of fabrics and a characteristic smell.
• Keep treated skin out of strong sunlight.
• Stop if the skin becomes sore, spotty or irritated and seek advice.

Evidence & guidelines

Coal tar with zinc oxide is an established topical preparation for chronic plaque psoriasis and eczema, used within stepped topical regimens recommended by NICE.