The balance between safety and efficacy is important in pharmacotherapy. When the indication of a registered drug shifts to another disease or a different patient population, studies on safety and... Show moreThe balance between safety and efficacy is important in pharmacotherapy. When the indication of a registered drug shifts to another disease or a different patient population, studies on safety and efficacy need to be performed. Ketamine is a relatively __old__ drug and used for almost 50 years as an anesthetic. Recently there has been a renewed interest for the treatment of therapy-resistant chronic pain with subanesthetic doses of ketamine. This thesis describes the effects of S-ketamine in patients with chronic pain (CRPS-1 and fibromyalgia patients) and healthy volunteers. In chronic pain patients (e.g. CRPS-1) pain relief can last for months after long-term intravenous ketamine infusions, but short-term S-ketamine had no long-term efficacy in fibromyalgia patients. S-ketamine can cause a wide range of side-effects which limits its use. Therefore studies were performed in healthy volunteers to expand the knowledge on S-ketamine and the main metabolite S-norketamine to further characterize side-effects (specifically neurocognitive effects). S-norketamine does not contribute to S-ketamine__s analgesic effects and can therefore not serve as an alternative. Show less
