1 Eight hundred patients were approached by questionnaire to give details of side effects of their antihypertensive medications. The response rate was 72.8%. The percentage of those questioned who were taking beta-adrenoceptor antagonists at the time was 54.6%. 2 Raynaud's phenomenon (P less than 0.05) and complaints of cold extremities (P less than 0.001) were significantly more frequent in women than in men, 74.8% of women complained of cold extremities. 3 Exposure to beta-adrenoceptor antagonists did not increase the prevalence of Raynaud's phenomenon in either men or women in the study, but did increase the prevalence of cold extremities in men (P less than 0.001). Propranolol, labetalol, oxprenolol and possibly atenolol were likely to produce such side effects. Smoking and the addition of vasodilators did not alter the effect of beta-adrenoceptor blockers on peripheral vascular symptoms. Complaints of cold extremities were not associated with an excess of complaints of other side effects.