With antibiotic stewardship now required in hospitals and increasingly normalized in other healthcare settings, dental offices are something out of an outlier.

Many dentists still routinely require antibiotic prophylaxis be taken before procedures, particularly for patients with joint replacements. A study presented recently in Washington, DC, at the IDWeek 2019 conference underscored that these routinely administered drugs may cause patient harm and contribute to the broader problem of antibiotic resistance.

The study included 168,420 dental visits with antibiotic prophylaxis, which the researchers describe as “unnecessary” in 80% of the cases.

Moreover, 3.8% of these unnecessary prescriptions were associated with an adverse event that included Clostridioides difficile infection, allergic reaction, anaphylaxis, or a visit to an emergency department.

“If you look across the United States at a population level, dentists prescribe 10% of all antibiotics annually,” said Katie J. Suda, PharmD, MS, research health scientist at the Hines (IL) VA Hospital.

For comparison, pediatricians and internists prescribe about 10% to 12% of antibiotics annually, she added.

“Antibiotics are not benign and this 4% represents a large number of people,” said Tom Talbot, MD, MPH, the vice-chair of IDWeek who moderated the session on antibiotics in dentistry. “This study helps further the discussion, illustrating in a very large population that it is not a harmless decision to give somebody one dose of antibiotics. There can be consequences.”

Using an insurance claims database, the researchers analyzed patients with dental visits from 2011-2015. To meet criteria, patients with commercial dental insurance had to be without a hospitalization or oral infection 14 days prior to antibiotic prophylaxis, which was defined as given for two days or less within one week before a dental visit.

Unnecessary antibiotic prophylaxis was defined as antibiotic prophylaxis in patients “who both did not undergo a procedure that manipulated the gingiva/tooth periapex and did not have an appropriate cardiac diagnosis,” the authors reported.

The 3.8% of patients who had an adverse reaction likely did not return to the dentist’s office, Suda said.

“They are going to their primary care provider or perhaps an emergency department,” she said. “So, dentists never really see these adverse outcomes. We think this is a conservative estimate because we did not include adverse events like nausea or diarrhea where the patient did not seek healthcare.”

Antibiotic prescribing among dentists has remained stable, while drug administration is declining in physicians due to stewardship efforts. Dentists are the top prescriber of clindamycin in the United States, the authors report, noting that historically, clindamycin has been associated with the highest rate of C. diff infection.

“We found in this study that clindamycin was associated with about a 34% increase in risks of having an adverse drug event - when compared to amoxicillin,” Suda said.

Of course, these dental prophylaxis decisions are not being made in a vacuum. Though the authors note there is no longer a standing recommendation to administer prophylactic antibiotics routinely before dental care, orthopedic surgeons may beg to differ.

“There is some controversy - especially in the orthopedic community - whether or not an antibiotic should be prescribed in dental patients who have orthopedic implants,” Suda said, “but those guidelines have changed, and it is no longer a recommendation for patients to routinely receive antibiotics prior to dental visits even if they do have a prosthetic joint.”

While there has been some historical divergence in the guidance on this issue, there was an attempt to reconcile the issue in a 2017 document by both surgical and dental groups.2 The conventional wisdom seems to be that routine, blanket prophylaxis is unnecessary, but antibiotics may be part of a dental plan of care in some orthopedic patients.

“Dentists should be part of the antibiotic stewardship conversation, but overall in healthcare we should try to provide dentists with more streamlined access to the patient’s medical information,” Suda said. “Very few dental practices have that kind of information available to them.”

Guidelines for antibiotic prophylaxis for heart patents under dental care have also been tapered down, Suda noted. Prophylaxis is recommended only for “those patients with cardiac conditions at the highest risk of an adverse outcome if they do get an endocarditis infection,” she said.

The IDWeek researchers urged patient involvement in the issue, raising awareness so an informed decision can be made on antibiotic prophylaxis with their doctors and dentists.

“We suspect that the dentists are prescribing the majority of these of course in what is often a multidisciplinary decision,” said co-author Alan E. Gross, PharmD, clinical assistant professor at the University of Illinois-Chicago.


  1. Gross AE, Suda KJ, Zhou J, et al. Serious antibiotic-related adverse effects following unnecessary dental prophylaxis in the United States. Abstract 895. IDWeek 2019. Washington, DC, Oct. 2-6, 2019.
  2. Quinn RH, et al. Management of patients with orthopaedic implants undergoing dental procedures. J Am Acad Orthop Surg 2017;25:e138-e141. doi:10.5435/JAAOS-D-17-00006.