Many people who have undergone subarachnoid hemorrhage from an aneurysm (an artery of a vein in the brain) struggle with a pronounced fatigue as well as a number of other sequelae such as impaired concentration, memory deficits and emotional problems. Exhaustion is often permanent and can lead to a significant worsening of quality of life and be the cause of disability. This condition does not only have major consequences for the individual who is affected, but also for their families and for society. So far no effective treatment for fatigue has been found. The drug OSU6162 has shown a beneficial effect on fatigue and other impairments after stroke and after traumatic brain injury. There is good reason to believe that OSU6162 can also improve fatigue and other impairments after aneurysm bleeding and thus increase the chance of returning to the level of daily function they had before the bleeding. The study is double blinded and measures the effect of OSU6162 and placebo on fatigue and neuropsychological function.