Premedication for Dental Treatment

What is Premedication?

Premedication is a medication that is administered in advance of invasive dental or medical procedures.

Premedication in the dental office is usually a prescribed dose of antibiotics taken by patients with certain medical conditions before an invasive dental procedure.

Why do we prescribe it?

The oral cavity is a portal of entry as well as a site of disease for microbial infections that affect a patient’s overall general health.

Patients are given premedication with the belief that antibiotics would prevent infective endocarditis (IE), previously referred to as bacterial endocarditis.

Streptococcus viridan is the main infective bacteria that can enter the bloodstream from procedures that cause considerable bleeding in the oral cavity.

When the bacteria enters the bloodstream it can lodge on the heart valves, inflame the myocardium and cause ulcerations on the inner walls of the artery.

Patients with artificial joints, structural heart defects, prostheses, or previous severe infections are at a higher risk. The risk of developing endocarditis is closely associated with some dental procedures, making it a concern for heart patients and people with compromised immune systems.

Oral streptococci account for one-third of all cases of endocarditis.

Premedication is prescribed to help prevent any bacteria introduced from the dental procedure, from causing an infection in another part of the body, such as the heart lining, or artificial joint.

Who needs premedication?

This subject is a debate, there is conflicting evidence whether antibiotic dental premedication is needed at all, and that the overprescription of antibiotics can lead to antibiotic-resistant strains of bacteria.

If significant bleeding is not going to occur, it is not necessary to take antibiotics prophylactically before your dental appointment.

You will be able to determine whether or not a patient will need premedication based on their medical history. If you are not sure consult the patient’s physician prior to treatment.

Prophylaxis Recommendations: Infective Endocarditis (IE)

With input from the ADA, the American Heart Association (AHA) released the current recommendations for the prevention of infective endocarditis in 2008.

The complete recommendations, including the recommended regimen, can be found in:

The Journal of the American Dental Association (JADA): Prevention of Infective Endocarditis: Guidelines from the American Heart Association

Patient selection for premedication:

The current recommendations recommend the use of preventive antibiotics prior to certain dental procedures for patients with:

artificial heart valves
a history of infective endocarditis
a cardiac transplant that develops a heart valve problem

The following congenital (present from birth) heart conditions:*

unrepaired or incompletely repaired cyanotic congenital heart disease, including those with palliative shunts and conduits
a completely repaired congenital heart defect with prosthetic material or device, whether placed by surgery or by catheter intervention, during the first six months after the procedure
any repaired congenital heart defect with residual defect at the site or adjacent to the site of a prosthetic patch or a prosthetic device

* Patients should check with their cardiologist if there is any question as to whether they fall into one of these categories.

Patients who took prophylactic antibiotics in the past but no longer need them to include those with:

mitral valve prolapse
rheumatic heart disease
bicuspid valve disease
calcified aortic stenosis
congenital (present from birth) heart conditions such as ventricular septal defect, atrial septal defect, and hypertrophic cardiomyopathy

Dental procedures

Premedication is recommended for all dental procedures that involve manipulation of gingival tissue or the periapical region of the teeth, or perforation of the oral mucosa.

Additional considerations about antibiotic prophylaxis:

Sometimes patients forget to pre-medicate prior to their appointments. The recommendation is that the antibiotic is given before the procedure. This is important because it allows the antibiotic to reach adequate blood levels.

However, the recommendations to prevent infective endocarditis state:

“If the dosage of antibiotic is inadvertently not administered before the procedure, the dosage may be administered up to two hours after the procedure.

Another concern that dentists have expressed involves patients who require prophylaxis but are already taking antibiotics for another condition.

In these cases, the recommendations for infective endocarditis recommend that the dentist select an antibiotic from a different class than the one the patient is already taking.

For example, if the patient is taking amoxicillin, the dentist should select clindamycin, azithromycin, or clarithromycin for prophylaxis.

What is the dose / Regimen given?

For reference, the standard regimen is as follows:

Adult Dosage:

Amoxicillin 500mg

Disp: 4 tablets.

Sig: Take all 4 tabs (2000mg) one hour before the procedure

For allergy to penicillin:

Clindamycin 300mg

Disp: 2 tablets

Sig: Take 2 tabs (600mg) one hour before appt

The full report is available to download below, along with supporting charts. If you have any questions about these guidelines, please feel free to contact the ADA Division of Science via e-mail or by calling 312-440-2878.

https://www.ada.org/2157.aspx?currentTab=2

https://www.americanheart.org/presenter.jhtml?identifier=3047051