Tea tree oil at a 5 percent concentration may have some effect on the symptoms of seborrheic dermatitis, writes the National Center for Biotechnology Information. Application of tar has also been shown to be effective, but there are questions about the safety of using tar for treatment of seborrheic dermatitis.
The cause of seborrheic dermatitis is not fully understood, reports the NCBI, but the condition appears to be related to over-proliferation of certain yeast strains. Treatment is therefore often symptomatic in nature. Tea tree oil has been shown to be generally safe for use in treating seborrheic dermatitis through topical application, though skin irritation may occur in sensitive individuals.