News Release

Study finds lower dose of ketamine equally effective in reducing pain

Peer-Reviewed Publication

Loyola Medicine

MAYWOOD, IL - A recent Loyola Medicine study found that reducing the standard dose of IV-administered ketamine in half is as effective as the larger, standard dose in reducing pain in adults.

Ketamine is known to provide pain relief comparable to opioid medications, which are highly addictive. In the recent study, appearing in the journal Academic Emergency Medicine, researchers studied 98 patients, ages 18 to 59, who presented to the emergency department with acute, moderate to severe pain. The patients were randomized prospectively to receive either 0.15 mg/kg of ketamine (low dose) or 0.30 mg/kg (high dose). Patients and providers were blinded to dose, with the primary outcome of pain measured on the 11-point numerical rating scale (NRS) at 30 minutes. At 15 minutes, the high dose group had a greater decrease in pain on the NRS but more adverse events. At 30 minutes, adverse events and pain were similar.

Overall, patients generally reported that they would take ketamine again for pain - 75.6% in the low-dose group and 61.7% in the high-dose group.

"We challenged the conventional ketamine dose used to treat pain," said lead study author Shannon Lovett, MD, emergency medicine physician at Loyola University Medical Center (LUMC) and associate professor in the Department of Emergency Medicine at Loyola University Chicago Stritch School of Medicine. "Our study should help demonstrate that a lower dose is sufficient to treat pain."

The study did not find a significant reduction in side effects from the lower dose.

"As we continue with our research, we hope to find data that supports diminished side effects with the lower dose of ketamine with equal efficacy in treating pain," said senior study author Megan A. Rech, emergency medicine clinical pharmacist at LUMC and an adjunct assistant professor and research coordinator at Stritch.


About Loyola Medicine

Loyola Medicine, a member of Trinity Health, is a nationally ranked academic, quaternary care system based in Chicago's western suburbs. The three-hospital system includes Loyola University Medical Center, Gottlieb Memorial Hospital and MacNeal Hospital, as well as convenient locations offering primary care, specialty care and immediate care services from more than 1,800 physicians throughout Cook, Will and DuPage counties. Loyola is a 547-licensed-bed hospital in Maywood that includes the William G. & Mary A. Ryan Center for Heart & Vascular Medicine, the Cardinal Bernardin Cancer Center, a Level 1 trauma center, Illinois's largest burn center, a certified comprehensive stroke center and a children's hospital. Loyola also trains the next generation of caregivers through its academic affiliation with Loyola University Chicago's Stritch School of Medicine and the Marcella Niehoff School of Nursing. Gottlieb is a 247-licensed-bed community hospital in Melrose Park with the newly renovated Judd A. Weinberg Emergency Department, the Loyola Center for Metabolic Surgery and Bariatric Care and the Loyola Cancer Care & Research facility at the Marjorie G. Weinberg Cancer Center. MacNeal is a 374-licensed-bed teaching hospital in Berwyn with advanced medical, surgical and psychiatric services, acute rehabilitation, an inpatient skilled nursing facility and a 68-bed behavioral health program and community clinics. Loyola Medical Group, a team of primary and specialty care physicians, offers care at over 15 Chicago-area locations. For more information, visit You can also follow Loyola Medicine on LinkedIn, Facebook or Twitter.

About Trinity Health

Trinity Health is one of the largest multi-institutional Catholic health care delivery systems in the nation, serving diverse communities that include more than 30 million people across 22 states. Trinity Health includes 92 hospitals, as well as 100 continuing care locations that include PACE programs, senior living facilities, and home care and hospice services. Its continuing care programs provide nearly 2.5 million visits annually. Based in Livonia, Mich., and with annual operating revenues of $18.8 billion and assets of $30.5 billion, the organization returns $1.3 billion to its communities annually in the form of charity care and other community benefit programs. Trinity Health employs about 123,000 colleagues, including 6,800 employed physicians and clinicians. Committed to those who are poor and underserved in its communities, Trinity Health is known for its focus on the country's aging population. As a single, unified ministry, the organization is the innovator of Senior Emergency Departments, the largest not-for-profit provider of home health care services -- ranked by number of visits -- in the nation, as well as the nation's leading provider of PACE (Program of All Inclusive Care for the Elderly) based on the number of available programs. For more information, visit You can also follow Trinity Health on LinkedIn, Facebook or Twitter.

About Stritch School of Medicine

Founded in 1909, Loyola University Chicago's Stritch School of Medicine is one of only four Catholic-affiliated medical schools in the nation. This fall, Stritch welcomed 170 students from 75 colleges to its 2024 class out of more than 14,000 applicants. With its academic medical center partner Loyola Medicine, Stritch clinical and basic science faculty help train the next generation of physicians and scientists. Learn more about Stritch, "like" us on, or follow us on Twitter @LoyolaHSD.

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