Dental Antibiotic Premedication: 10 Common Questions

Dental Antibiotic Premedication: 10 Common Questions

Dental Antibiotic Premedication Common Questions

Many dental procedures cause bleeding in the mouth, which can allow the bacteria in the mouth to enter into the person’s bloodstream.  Certain people are more susceptible to bacterial infections in their bloodstream than others.  In order to prevent bacteria from living in your bloodstream and infecting certain high risk areas of your body, it is important for certain people to take antibiotics before having many dental procedures.  This is known as antibiotic premedication or antibiotic prophylaxis.

Many people have questions regarding antibiotic premedication and dental work.  Here’s a list of ten common questions and their answers.  If you have any other questions about antibiotic premedication that I don’t cover in the following article, feel free to leave a comment down at the bottom.

Dental Antibiotic Premedication: 10 Common Questions

1 – Who needs to be premedicated before having dental work done?

Basically, if you have any of the following, your dentist may consider giving you antibiotics before routine dental work:

  • Artificial joint replacement
  • A previous heart infection (infective endocarditis)
  • A prosthetic heart valve
  • Certain cases of congenital heart disease
  • Heart transplant patients who have developed cardiac vulvopathy
  • Certain immune conditions

For a more in-depth look at who needs to be premedicated before dental work, read the article Why You Might Need to Premedicate with Antibiotics Before Seeing Your Dentist.

2 – If I have artificial screws, pins, or plates in my joints, or if I have had a stent placed in my heart, should I premedicate?

Antibiotic premedication before dental procedures is not required for any of those conditions.  It is only required for the conditions given by the American Heart Association, the American Dental Association and the Academy of Orthopaedic Surgeons (AAOS).  The AAOS has stated, “patients with pins, plates and screws, or other [orthopedic] hardware that is not within a synovial joint are not at increased risk for hematogenous seeding by microorganisms.”

3 – My dentist told me to take 4 tablets of amoxicillin before my dental appointment.  That’s 2,000 milligrams of antibiotic!  That seems like too much, did my dentist really mean 200 mg?  Did he make a mistake on the prescripition?

The American Heart Association guidelines recommend 2,000 milligrams of amoxicillin for antibioitic premedication before dental procedures.  A “normal” dosage of an antibiotic such as penicillin or amoxicillin is 500 milligrams a few times per day.  From that perspective, 2,000 milligrams is simply the amount of antibiotic that you might take in one day if you were using it to fight an infection.

4 – My dentist used to give me antibiotics before dental work but she doesn’t give them to me anymore.  Nothing in my health history has changed.  Why?

The guidelines for antibiotic premedication are constantly changing as new scientific evidence is discovered.  It is likely that your dentist is simply following the new guidelines.  For example, the guidelines changed for heart problems in 2008 and now we do not premedicate many patients that required antibiotic premedication prior to the new 2008 guidelines.

5 – According to question #1 above, I need to be premedicated before getting dental work done.  Do I need to be premedicated for all dental procedures?

No, only certain dental procedures require antibiotic premedication.  You can find a list of the procedures that do require antibiotic premedication in the article Why You Might Need to Premedicate with Antibiotics Before Seeing Your Dentist.

As a general rule, if you expect to be bleeding around your gums during the procedure, you probably need to be premedicated for that procedure.

6 – Even if my condition isn’t listed on the new guidelines, can I still premedicate just to be on the safe side?

If your condition is no longer listed as someone who is at risk for a bacterial infection, then you don’t need to be premedicated before having dental work done.  If there were a substantial risk of you getting an infection, your condition would be listed in the guidelines.

7 – I still want antibiotics, but my dentist won’t give them to me.  What should I do?

Your dentist is doing you a favor.  You really don’t need antibiotics, and the risks (allergy, upset stomach, antibiotic resistance) all outweigh the benefits.

8 – My doctor told me that I still need to be premedicated before dental work, but my dentist won’t give me a prescription for antibiotics because he says that they are not needed.  Who’s right, the doctor of the dentist?

You can have your dentist call your doctor to see if there are any reasons for you to be premedicated.  In my experience, many doctors have not implemented the new guidelines and prefer to do things as they have always done.

For more information on this predicament, read the article Antibiotic Premedication: When Your Doctor and Dentist Disagree.

9 – I am already taking antibiotics for an infection, so I don’t need to premedicate since I am already taking antibiotics, right?

Wrong.  If you are taking antibioitics for one infection and you need to be premedicated, you need to take another antibiotic.  The American Dental Association has said the following: “Another concern that dentists have expressed involves patients who require prophylaxis but are already taking antibiotics for another condition. In these cases, the guidelines 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.”

10 – I forgot to take my antibiotics before my dental appointment, but I lied to my dentist and told him I did because I had already taken the time off work and I can’t take any more time off.  Is this alright?

If you don’t take the antibiotics, you are at an increased risk for developing an infection.  For example, the bacteria in your mouth can travel to your heart and cause a heart infection known as infective endocarditis.

However, there is hope!  The guidelines from the American Heart Association say, “If the dosage of antibiotic is inadvertently not administered before the procedure, the dosage may be administered up to two hours after the procedure.”  If it hasn’t been 2 hours, you can still take the antibiotics!

Bonus Question 11 – Do I need to premedicate if I have breast implants?

Pat asked this question a while back in the comments section on one of my earlier articles about antibiotic premedication.

Basically, there is only one reported case of a breast implant infection following dental work.  Even that case isn’t very strong since researchers were unable to confirm that the strain of bacteria that caused the infection actually was from bacteria in her mouth.

The California Dental Association has stated, “The prudent dentist should always weigh the risk of prophylactic antibiotic therapy against the potential benefit in a particular group of patients. For the hundreds of thousands of women with breast implants, the decision not to prescribe prophylaxis is clearly justified. If the patient’s plastic surgeon is adamant about the necessity of antibiotic prophylaxis, then that physician should write the prescription.”

Obviously, the risk of getting an infection in a breast implant from a dental procedure is extremely low, and thus it is not necessary to take antibiotics before dental work for a breast implant.

You can read my full response to Pat’s question here.


Do you have a question about antibiotic premedication before dental work that I didn’t cover above?  Go ahead and ask it in the comments section below.  Thanks for reading!

References and further information: Lexi Comp Online, ADA Prophylaxis


  1. I had second state implant surgery yesterday, i took 2000mg amoxicillian one hour prior, my left gum did bleed for a while after surgery, I took 1000mg six hours later, I do have total r knee replacement, Dentist said I did not need any further antibiotic, Is this ok
    Thank you for your response

  2. I am scheduled in few weeks for tooth implant. My dentist prescribed Amoxicilline 500mg 3 times a day for 7 days. It seems that the dose is too big.

    Right now I am on the dose of 500mg once a day for 6 days from broncitys and it working

    Thank you,

    • Hi Ella – Did you inform your dentist that you were already taking amoxicillin? We normally prescribe a different antibiotic for premedication if you’re already taking amoxicillin. I would discuss your concerns with your dentist. I hope the implant goes well!

  3. Hi Tom,

    For some unknown reason, I misread the directions on my Clindamycin bottle and took the 4 pills 4 hours prior to my dental work, rather than 1 hour. Does this mean that I need to take the medication AFTERWARDS just to make sure that I don’t get an infection?

    Thank you

  4. I have a plate in my ankle and went to the dentist a few weeks ago for a teeth cleaning and forgot to premedicate. Do I have to worry about an infection?

  5. I have three dental appointments scheduled, once a week for three weeks. Is that too much Amoxicillin (2000 mg each time)?

    • Hi Clair – That is the recommended amount. If you’re concerned, you could talk to your dentist about possibly condensing it into longer appointments, or perhaps only doing procedures in one appointment that wouldn’t require antibiotic premedication. I hope that helps!

      • Yeh, pretty hard to do…I’m having a crown replaced on one visit, and the other two visits are two hours each : /

        Just wanted a second opinion….seemed like a lot of antibiotics in a short time.


  6. We have a lot of patient that forget to take their pre-med at home prior to their dental appointment. We administer it to them in office. Can we charge them for this? If so, is there a dental code to use? Will insurance cover it?

    Thank you!

  7. I had surgery to replace my aortic valve with a tissue one on 4th April this year. I need to go to the dentist for dental cleaning, scaling and 2 fillings. I have some mild gingivitis and mild to moderate peritonitis.
    My cardiologist says I should premeditate with 2gm Amoxycillin. However I’m not happy to take the antibiotic due to the fact that it will upset and destroy all of the good bacteria in my stomach.
    The NICE (2008) guidelines in the UK clearly state that pre med antibiotics are not useful or recommended for all dental procedures no matter what your medical condition. It’s just as easy to get endocarditis through routine dental cleaning and flossing. I think my cardio is just following the American Heart Association guidelines.
    Any advice?

  8. I have an artificial heart valve and forgot to take my antibiotic medication prior to dental cleaning and dental tech didn’t remind me prior to procedure. Realized this approx 14 hours after procedure. What should I do???

  9. My dentist asked me to have 2 gms of antibiotic few hours before dental procedure.. but my cardiologist asked me to have it 4 pieces (500 mg *4) a day before. on my reading thro’ web pages, I inferred that Amoxillin will not last in blood for more than 5 hours. If that is the case, is my cardiologist opinion still valid ? Please advise

  10. I forgot to take my antibiotics before my dental appointment 4 days ago . I just realized it today. It was a emergency filling. Half of a tooth had to be refilled. What do I need to do?

  11. I forgot to take my antibiotics before my dental appointment 4 days ago . I just realized it today. It was a emergency filling. Half of a tooth had to be refilled. What do I need to do?i had a knee replacement 14 months ago.

  12. I had knee replacement 14 months ago. I forgot to take antibiotics 4 days ago. I had a emergency tooth filled then. What do I need todo ?

  13. How many days between dental appointments if I have to pre-med 2000 mg amoxicillian before appointment? Waiting for your response. Please e-mail me. Thanks you Kay :)

Leave a Reply