Danish paracetamol (PCM) poisoned patients are treated with N-acetylcysteine (NAC) intravenously for 36 hours. This probably leads to overtreatment. Today, patients with poor prognoses can be identified and, in addition, NAC may have serious side effects. We reviewed the literature (route of administration, duration and timing of treatment) and found that intravenous NAC often leads to side effects (some serious), primarily when serum paracetamol is low. These patients are often only mildly poisoned and they may therefore benefit from a shorter, orally administered regimen (equally efficient and with fewer side effects than intravenously administered NAC).