I m glad you asked this question. Olanzapine (Zyprexa in the USA) is an atypical antipsychotic medication that is also approved as a mood stabilizer and augmenting agent to antidepressants. This medication has caused more lawsuits in the USA than you could imagine because of its propensity to cause diabetes, high cholesterol and high blood pressure in those who take it. Unfortunately, when the diabetes occurs from this drug, it may not be reversible when the drug is stopped. In cases such as that, medications or insulin (or both) must be given to the patient to treat the diabetes. Medications for diabetes can cause erectile dysfunction and so can olanzapine itself. This can sometimes be offset with Viagra (sildenafil) or Cialis (tadalafil). If someone develops diabetes while on olanzapine, lowering and stopping that medication is often the way to proceed, to see if the diabetes resolves. If it does not resolve, the decision then has to be made as to whether to continue the olanzapine while treating the diabetes, or switching to another medication at that point. I am in the USA and not Europe so I cannot unfortunately recommend a good European diabetes clinic. Perhaps another physician on our panel can do that for you. Thanks for your question and best of health to you!