Postoperative analgesia should be adjusted to current needs of a patient. Non-opioid agents are recommended, wherever possible: both non-steroidal anti-inflammatory drugs (NSAIDs), metamizole or paracetamol may be useful for treatment of acute pain. The use of metamizole is associated with such complications as bone marrow damage (agranulocytosis, aplastic anaemia), chronic interstitial nephritis, gastro-intestinal disturbances, etc. Paracetamol, currently also intravenous, is likely to cause hepatocyte damage, renal necrosis, as well as vomiting, diarrhoea and skin reactions. Opinions about metamizole are controversial. In some countries, metamizole was withdrawn already in the 70ties of the previous century; in others, it is still widely used. According to the Uppsala Monitoring Centre, WHO Collaborating Centre for International Drug Monitoring, the number of adverse effects registered in the years 1978-2009 (March) was 14441 for metamizol and 67581 for paracetamol. Modern multimodal analgesia should be based on a good combination of analgesics. Both metamizole and paracetamol may be used for such a purpose, yet in the lowest effective doses, within the shortest needed time and once evident contraindications have been considered. Safety of both drugs is several times higher than that of commonly used NSAIDs.