Study on the effects of tablet colour in the treatment of anxiety states.

Forty-eight patients with anxiety states were treated with oxazepam (Serenid-D), which was administered in tablets of three different colours-red, yellow, and green. Every patient received one week's treatment with each colour, according to a random programme. A latin square design was used to ensure complete balance between the colours and between the weeks. The patients' symptoms were categorized and then assessed by both weekly physicians' ratings and daily self-rating, which showed close agreement. Colour preference was shown on both these scales in that symptoms of anxiety were most improved with green, whereas depressive symptoms appeared to respond best to yellow. Such colour preferences, however, did not reach levels of statistical significance, except for phobias as rated on the physicians' assessment.The results indicate that colour may play a part in the response to a drug.