Some patients with sarcoidosis can have cardiac involvement. Impairment of the cardiac sympathetic nerve activity is seen in about 50% of the sarcoidosis patients with small fiber neuropathy. In this case we present a sarcoidosis patient with small fiber neuropathy and cardiac symptoms with a cardiac sympathetic dysfunction, assessed with I-123 MIBG SPECT. After 5 months of treatment with carvedilol, which has besides adrenergic receptor blocking effects also antioxidant action, we saw a clear improvement of the cardiac sympathetic function demonstrated on a repeated I-123 MIBG SPECT. Future studies should explore the clinical relevance of the relation of oxidative stress, antioxidant therapy and cardiac dysfunction in sarcoidosis.