American dentists wrote more than 2.3m prescriptions last year for an antibiotic called clindamycin, whose label has carried a black box warning for more than four decades, due to its high rate of life-threatening complications, reports CIDRAP News.
One of those prescriptions was given to Dolores Owens (92), in California, who needed an extraction a year ago and whose dentist prescribed clindamycin, the second-most commonly used drug in dentistry.
But within days of her surgery, Owens developed severe stomach pain, nausea, loss of appetite, headaches, and frequent severe bouts of diarrhoea. She was admitted to hospital where she spent a week, after her doctor diagnosed colitis, an inflammation of the colon.
She was sent home with more antibiotics.
Although her symptoms improved at first, they returned with a vengeance after about a week. When Owens visited a second hospital a few weeks later, she learned her illness was caused by an infection with Clostridioides difficile – C difficile or C diff – a bacterium that releases toxins that can destroy the lining of the intestine.
Neither she nor her family knew that C difficile infections are closely related to antibiotic use.
More than half of people who develop these infections outside a hospital have taken antibiotics, research shows. Of those people, 15% were prescribed antibiotics because of a dental procedure.
A dangerous trend
Although taking any antibiotic can lead to C difficile, which sickens half a million Americans a year and kills nearly 30 000, clindamycin has long been known to pose an especially high risk.
“Clindamycin is notorious for causing C diff infections,” said Amesh Adalja, MD, a senior scholar at the Johns Hopkins Centre for Health Security and infectious disease specialist who has treated many patients with C difficile. “Yet clindamycin is one of the go-to antibiotics for dentists.”
Many dentists prescribe antibiotics to healthy patients to prevent potential infections, despite research that finds 80% of these antibiotics are unnecessary.
In addition to increasing the risk of C difficile infections, prescribing unnecessary antibiotics increases the risk of antimicrobial resistance (AMR), which has made antibiotics and other infection-fighting medications less effective, and which contributes to an estimated 5m deaths a year worldwide.
For years, experts and professional societies have recommended that dentists tamp down their use of antibiotics, especially clindamycin, to reduce the risks to patients.
A CIDRAP News investigation found that the message isn’t getting through. In spite of repeated warnings about the risks, dentists continue to prescribe antibiotics in large numbers, often inappropriately.
Instead of declining, antibiotic prescribing by dentists increased by 6% from 2020 to 2025, when the profession wrote more than 27m antibiotic prescriptions, according to data provided to CIDRAP News from IQVIA Institute for Human Data Science, which provides research and analysis on healthcare data.
Although dental prescriptions for clindamycin decreased 35% from 2020 to 2025, it remains the profession’s second-most commonly prescribed antibiotic, according to IQVIA’s National Prescription Audit.
“The data suggest that antibiotics are massively overprescribed in dentistry,” Adalja said.
The decline in clindamycin use “isn’t enough”, considering its life-threatening risks, he said. “Dentists are still using it too much.”
Elliot Abt, DDS, who co-wrote antibiotic guidelines for the American Dental Association (ADA), said he’s disappointed that clindamycin is prescribed more often than all but one antibiotic.
“I would have liked to see it at or near the bottom of the list,” said Abt, adjunct associate Professor of Oral Medicine at the University of Illinois College of Dentistry. “Changing practitioners’ behaviour is a slow and challenging process.”
A heartbreaking physical decline
C difficile ravaged Owens’ small body – she developed sepsis, a life-threatening complication of C difficile in which the immune system over-reacts to infection in a way that damages multiple organs.
She bled internally, losing so much blood that her doctor ordered a transfusion: she became dehydrated, weak, and light-headed.
Eventually, her hands, arms, and legs became swollen, and the skin on her arms became discoloured. Her family hesitated to apply hand lotion to Owens’ skin for fear that it would tear.
They remain haunted by her suffering, and by one question: why are dentists still prescribing clindamycin?
Doing as they were taught
For decades, dental schools taught dentists to prescribe antibiotics to prevent procedure-related infections, Abt said.
They were taught to prescribe drugs like the penicillin amoxicillin, because of its effectiveness and safety record. For patients like Owens, whose medical record listed a penicillin allergy, they were taught to prescribe clindamycin.
Because bacteria from the mouth can travel around the body, they were taught to prescribe antibiotics to patients with certain heart conditions to prevent a rare but dangerous infection of the lining of the heart and valves – infective endocarditis, Abt said.
They also routinely prescribed antibiotics to people with artificial joints, even if they were otherwise healthy, for fear that the joints could become infected, said Antonia Chen, MD, MBA, Chair and Professor of Orthopaedic Surgery at University of Texas Southwestern.
Experts began to rethink these recommendations as the risks of clindamycin became more apparent. In 2015, researchers reported that a single dose of clindamycin could cause serious complications, including deaths, related to C difficile.
“Dentists did not believe that their prescribing was associated with resistance or C difficile because they perceived their prescribing to be of short duration,” said Katie Suda, PharmD, a Professor of Medicine at the University of Pittsburgh.
“They felt that one dose of antibiotic before a dental procedure was not associated with an adverse event.”
Although a dentist can check a database to see if someone has been prescribed opioids, there’s usually no way for dentists to learn which antibiotics a patient has taken, said Erinne Kennedy, DDS, a board member of the Association for Dental Safety. That’s because doctors and dentists tend to use incompatible electronic health record systems that can’t share information.
See more from MedicalBrief archives:
Dentistry: No endocarditis increase with end to antibiotic prophylaxis – Karolinska Institutet
Antibiotics prescribed for dental patients unnecessary 81% of the time
UK man calls for guideline changes after near death linked to tooth extraction
World leaders pledge to slash AMR by 10%