Controlled-release opioid may be leading to heart infections in persons who inject drugs

January 22, 2020

LONDON, ON - A new study from ICES, Lawson Health Research Institute and Western University suggests that injection drug users prescribed controlled-release hydromorphone are three times more likely to develop endocarditis, a serious bacterial heart infection, when compared to those prescribed other opioids. The findings, published today in The Lancet Infectious Diseases, build on growing evidence that some controlled-release opioids may lead to higher risk of infectious disease among persons who inject drugs.

The researchers looked at de-identified Ontario health data for hospital admissions related to injection drug use between 2006 and 2015. Of 60,529 admissions, 733 patients had infective endocarditis. The team found that regions with high hydromorphone prescription rates had more than double the cases of infective endocarditis (254 cases) when compared to regions with low prescription rates (113 cases).

The study also analyzed individual prescription records and found that among persons who inject drugs, those prescribed controlled-release hydromorphone were three times more likely to develop infective endocarditis when compared to those prescribed any other opioid. There was no increased risk for those prescribed the immediate-release form of hydromorphone.

"Added to the existing data, these findings make a compelling argument for the role of controlled-release hydromorphone in the growing risk of infective endocarditis among persons who inject drugs," says Dr. Matthew Weir, Adjunct Scientist at ICES, Associate Scientist at Lawson and Assistant Professor at Western's Schulich School of Medicine & Dentistry.

Opioids are often manufactured as controlled-release or 'slow-release' capsules to prevent rapid absorption of the drug. Properties in the capsules help to spread pain relief over a longer period of time.

This is the latest in a series of studies from the research team that suggest some controlled-release opioids may be leading to increased risk of infectious disease among persons who inject drugs.

In one study, they demonstrated that polymer-coated beads used to provide the slow-release property make controlled-release hydromorphone difficult to dissolve. They found equipment used to dissolve the drug retains up to 45 per cent of the initial dose, leading injection drugs users to save and reuse equipment.

With frequent re-handling of equipment, there are multiple opportunities for bacterial and viral contamination. The team found that HIV and a dangerous bacterium called Staphylococcus aureus are more likely to survive in equipment used to prepare controlled-release hydromorphone since added chemicals that make the drug slow-release promote survival of bacteria and viruses.

"There's been a global increase in infectious diseases among persons who inject drugs and our research suggests that controlled-release prescription opioids may be a major culprit," says Dr. Michael Silverman, Associate Scientist at Lawson and Associate Professor at Schulich Medicine & Dentistry. "We now have evidence that suggests the injection of controlled-release hydromorphone is increasing the spread of HIV, hepatitis C and endocarditis in Canada."

The team believes these findings could also explain the increase in infectious complications in the USA and other countries where controlled-release hydromorphone is not on the market. There are other controlled-release opioids, such as controlled-release morphine, that use a similar slow-release mechanism and may carry similar risks.

"It's important that people are aware of the infectious risks of injecting opioids and, if necessary, practice harm reduction techniques," says Dr. Silverman. "We've found you can use a cigarette lighter to destroy bacteria and viruses by heating the cooker used to prepare the drug for about 10 seconds or until the mixture bubbles. We've termed the technique 'cook your wash.'"
For downloadable media, please visit

MEDIA CONTACT: Robert DeLaet, Communications and External Relations, Lawson Health Research Institute, t. 519.685.8500 ext. 75664, c. 519.619.3872,

ICES is an independent, non-profit research institute that uses population-based health information to produce knowledge on a broad range of health care issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting health care needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners, and practitioners to make decisions about care delivery and to develop policy. In October 2018, the institute formerly known as the Institute for Clinical Evaluative Sciences formally adopted the initialism ICES as its official name. For the latest ICES news, follow us on Twitter: @ICESOntario


As the research institute of London Health Sciences Centre and St. Joseph's Health Care London, and working in partnership with Western University, Lawson Health Research Institute is committed to furthering scientific knowledge to advance health care around the world.


The Schulich School of Medicine & Dentistry at Western University is one of Canada's preeminent medical and dental schools. Established in 1881, it was one of the founding schools of Western University and is known for being the birthplace of family medicine in Canada. For more than 130 years, the School has demonstrated a commitment to academic excellence and a passion for scientific discovery.

Lawson Health Research Institute

Related Infectious Diseases Articles from Brightsurf:

Understanding the spread of infectious diseases
Physicists at M√ľnster University (Germany) have shown in model simulations that the COVID-19 infection rates decrease significantly through social distancing.

Forecasting elections with a model of infectious diseases
Election forecasting is an innately challenging endeavor, with results that can be difficult to interpret and may leave many questions unanswered after close races unfold.

COVID-19 a reminder of the challenge of emerging infectious diseases
The emergence and rapid increase in cases of coronavirus disease 2019 (COVID-19), a respiratory illness caused by a novel coronavirus, pose complex challenges to the global public health, research and medical communities, write federal scientists from NIH's National Institute of Allergy and Infectious Diseases (NIAID) and from the Centers for Disease Control and Prevention (CDC).

Certain antidepressants could provide treatment for multiple infectious diseases
Some antidepressants could potentially be used to treat a wide range of diseases caused by bacteria living within cells, according to work by researchers in the Virginia Commonwealth University School of Medicine and collaborators at other institutions.

Opioid epidemic is increasing rates of some infectious diseases
The US faces a public health crisis as the opioid epidemic fuels growing rates of certain infectious diseases, including HIV/AIDS, hepatitis, heart infections, and skin and soft tissue infections.

Infectious diseases could be diagnosed with smartphones in sub-Saharan Africa
A new Imperial-led review has outlined how health workers could use existing phones to predict and curb the spread of infectious diseases.

The Lancet Infectious Diseases: Experts warn of a surge in vector-borne diseases as humanitarian crisis in Venezuela worsens
The ongoing humanitarian crisis in Venezuela is accelerating the re-emergence of vector-borne diseases such as malaria, Chagas disease, dengue, and Zika virus, and threatens to jeopardize public health gains in the country over the past two decades, warn leading public health experts.

Glow-in-the-dark paper as a rapid test for infectious diseases
Researchers from Eindhoven University of Technology (The Netherlands) and Keio University (Japan) present a practicable and reliable way to test for infectious diseases.

Math shows how human behavior spreads infectious diseases
Mathematics can help public health workers better understand and influence human behaviors that lead to the spread of infectious disease, according to a study from the University of Waterloo.

Many Americans say infectious and emerging diseases in other countries will threaten the US
An overwhelming majority of Americans (95%) think infectious and emerging diseases facing other countries will pose a 'major' or 'minor' threat to the U.S. in the next few years, but more than half (61%) say they are confident the federal government can prevent a major infectious disease outbreak in the US, according to a new national public opinion survey commissioned by Research!America and the American Society for Microbiology.

Read More: Infectious Diseases News and Infectious Diseases Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to