Effects of Moxaverine and Placebo on Ocular Blood Flow

Inclusion Criteria: * Men and women aged between 18 and 35 years, nonsmokers * Body mass index between 15th and 85th percentile * Normal findings in the medical history and physical examination unless the investigator considers an abnormality to be clinically irrelevant * Normal laboratory values unless the investigator considers an abnormality to be clinically irrelevant * Normal ophthalmic findings, ametropy \< 3 dpt. Exclusion Criteria: * Regular use of medication, abuse of alcoholic beverages or drugs, participation in a clinical trial in the 3 weeks preceding the study * Treatment in the previous 3 weeks with any drug * Symptoms of a clinically relevant illness in the 3 weeks before the first study day * History or presence of gastrointestinal, liver or kidney disease, or other conditions known to interfere with distribution, metabolism or excretion of study drugs * Blood donation during the previous 3 weeks * Ametropy \>= 3 dpt * Acute gastric bleeding, massive cerebral hemorrhage related to stroke * Women: pregnancy or lactation