A drop of sugar water before a needle stick reduces pain in hospitalized newborns

Hospitalized newborns get stuck with needles. A lot. Blood draws, IV insertions, heel lances -- the procedures are medically necessary, often repeated, and painful. And in neonatal intensive care units around the world, many of these procedures are still performed without any pain management at all.

A Cochrane systematic review led by Mariana Bueno, an Assistant Professor at the University of Toronto's Lawrence Bloomberg Faculty of Nursing, has confirmed what many clinicians already suspected but needed rigorous evidence to act on: giving infants a small dose of sucrose (sugar water) on the tongue two minutes before venepuncture significantly reduces their pain response compared to doing nothing.

What the evidence shows

The review, which included studies from around the world, found that sucrose administration stood out as an effective and safe option for managing pain and providing comfort to babies during venepuncture. The effect was enhanced when infants were also given a pacifier -- a combination that Bueno described as making the analgesic effects "even better."

Venepuncture involves puncturing a vein, either for blood collection or to insert an IV line. When performed by a skilled clinician, it can be less painful than the alternative method of heel lancing, but it is often unsuccessful on the first attempt, meaning infants may endure multiple needle sticks in a single session.

"We know that procedural pain for infants is poorly managed in low, middle and high-income countries," Bueno said. "Repeated exposure to untreated acute pain at early stages in life may lead to short and long-term changes to the structure and connectivity of the somatosensory system -- essentially how the brain processes and perceives external stimuli."

Why untreated pain matters in newborns

The consequences of repeated procedural pain in early life extend well beyond the moment of the needle. Research has linked it to altered brain development, changes in pain processing, and negative effects on growth and neurodevelopment. Infants hospitalized for extended periods -- weeks or months in a NICU -- face the greatest cumulative exposure.

The developing brain is particularly sensitive to pain signals. Unlike adults, who can contextualize and modulate their pain experience, neonates lack the cognitive framework to understand that a needle stick is temporary. The physiological stress response is real, measurable, and consequential.

Simple to administer, hard to implement

Sucrose is administered by placing a small amount of sugar solution on the infant's tongue approximately two minutes before the procedure. The mechanism is not fully understood but is believed to involve activation of endogenous opioid pathways. It is classified as a medication and is already recommended in many infant care guidelines.

So why is it not used more often? Bueno identifies several barriers. NICUs are fast-paced environments where clinicians may rationalize that a quick procedure will not cause lasting harm, or that the infant will not remember the pain. Sucrose doses are not always readily available -- in some countries, supply is a genuine obstacle. And the broader culture of neonatal care has not consistently prioritized procedural pain management.

"There is a gap in the work being done to engage clinicians in changing their practice and using this evidence more intentionally when caring for hospitalized infants," Bueno said.

A hierarchy of options

Sucrose is not the only available intervention. Skin-to-skin contact (kangaroo care), breastfeeding, and topical anesthetics also reduce procedural pain. Bueno suggests a practical hierarchy: offer skin-to-skin contact first, then breastfeeding if available, and if neither option is feasible, administer sucrose. The core message is that something should be done before every needle stick.

"The message from our findings is ultimately that infants need and should receive pain management before a procedure such as venepuncture," Bueno said.

Unanswered questions

The review does not compare sucrose directly against other interventions like skin-to-skin care or breastfeeding in a head-to-head analysis. Bueno notes that further research is needed to establish relative effectiveness. There are also questions about the long-term effects of repeated sucrose administration -- whether giving sugar water multiple times daily to premature infants carries any metabolic consequences. Clinicians would need to be thoughtful about prescribing it only for procedural pain rather than as a general-purpose soother for crying or distress.

"These challenges can be addressed," Bueno said. "By using clinical practice guidelines and locally developed evidence-based protocols, we can improve pain care in NICUs."