A local cooling test produces a typical flow stop reaction in nailfold capillaries in 88% of patients with Raynaud's phenomenon, but only in 15% of healthy controls. A stop reaction occurred in 9 of 12 patients with Prinzmetal variant angina, exceeding significantly that in 2 of 12 matched control subjects. Also in patients with reversible visual disorders presumably due to vasospasm, the test resulted in a stop reaction in 16 of 25 cases exceeding that in control. In both of these patient groups the cooling test as well as the symptoms reacted favorably to nifedipine. Thus, the local cold exposure test appears to be useful for objective clinical examination not only of patients with Raynaud's phenomenon but also of patients with vasospastic syndromes such as variant angina and visual disorders.