Clinical pharmacology of analgesics in infants and the pharmacologic management of pain in neonates

OBJECTIVES: The objectives of this study are to describe (1) the clinical pharmacology of analgesics in infants and (2) the pharmacologic management of pain in neonates. METHODS: The bibliographic search was performed using PubMed and EMBASE databases as search engines. RESULTS: Opioid analgesics are the most commonly used analgesics for acute pain and they include intravenous morphine (50 to 200mg/kg), oral methadone (50 to 200mg/kg), intravenous fentanyl (0.5 to 4mg/kg), alfentanyl (10 to 20mg/kg), sufentanil (10 to 15mg/kg), and remifentanil (5mg/kg). Fentanyl, alfentanyl, sufentanil and remifentanil are short-action opioid analgesics. Non-opioid analgesics can be used for moderate pain; they include oral paracetamol (acetaminophen, 12 to 15mg/kg), the intravenous benzodiazepine midazolam (50 to 150mg/kg) which is not recommended in neonates, intravenous propofol (2.5mg/kg) which is used for induction of general anaesthesia, and ketamine, (2mg/kg intravenously or 4mg/kg intramuscularly) which produces a short-lasting, trance-like state with profound analgesia and amnesia. CONCLUSION: The use of non-opioid analgesics has increased in the last years for the management of non-acute pain. If prevention or elimination of pain is not possible, a more realistic goal may be to aggressively intervene to minimize pain and its effects.