he use of acetaminophen (paracetamol, APAP) in the neonatal intensive care unit (NICU) has become ubiquitous. Between 2005 and 2010, APAP was the 15th most common pharmacologic exposure among infants admitted to the Pediatrix-affiliated NICUs in the US. 1 Over nearly the same period of time, a significant increase in the use of APAP was reported in German NICUs, occurring in 8.1% of all infants with very low birth weights by 2010. 2 Since 2010, multiple reports indicate increasing APAP use in NI-CUs around the world. Data gathered in 2017-2018 from nearly 30 000 French infants showed that APAP was the third most commonly administered medication behind vitamin K and vitamin D and was given to >65% of all infants born at less than 27 weeks of gestation. 3 It is likely that this rapid increase in APAP exposure is primarily driven by the desire to provide analgesia and limit opioid exposure. In fact, one French NICU reported that by 2012-2013, nearly 95% of patients in the NICU postsurgery were administered APAP. 4 These data have been interpreted as demonstrating that "paracetamol is somehow a 'rising star' in NICU pain management." 5 The introduction of APAP into the NICU led to the chance observation that administration was temporally associated with closure of the patent ductus arteriosus (PDA). 6 In the time since this case series was published in 2011, the rise in annual publications in PubMed.gov demonstrate the rapidly growing interest in this pharmacologic approach to PDA treatment (Figure 1). Multiple case series, cohort studies, and ultimately randomized controlled trials (RCTs) evaluating APAP for PDA followed, and these have been summarized in a number of comprehensive reviews. [7][8][9][10][11][12][13] Based on the available data, a 2020 Cochrane review by Ohlsson and Shah concluded that moderate-quality evidence demonstrated that APAP is as effective as ibuprofen to treat PDA. 14 However, this review also noted that the results from the more than 19 registered and ongoing trials are necessary before any "recommendations for the possible routine use of paracetamol in the newborn population can be made." Specifically, the paucity of data