Taking the liquid formulation of amoxicillin has the greatest chance of staining your teeth but at least the discoloration isn't permanent since it can be removed. The pill/capsule form of the antibiotic seems to have a lower chance of staining occurring.
Amoxicillin can stain teeth
Yes, amoxicillin can cause brown, yellow, or grey stains on teeth but it is a very rare side effect since there have been very few reports of it. It seems to be more common in children and the theory is that the tooth staining may be due to liquid forms of amoxicillin.
Study about tooth discoloration and antibiotic use:
Staining is rare. From 1991-1996 only 25 cases of teeth staining were reported.
Due to liquid formulations. 14 of those cases were from amoxicillin use in children and they all involved a liquid formulation of amoxicillin (suspension or solutabs).
The theory is that the liquid form of the antibiotic can come into contact with the enamel and stick to it. The pill form on the other hand does not come into contact with teeth so it is less prevalent.
Color of amoxicillin stains - brown, yellow or grey.
Rare side effect - very infrequently reported
Studies and case reports of this discoloration phenomenon are quite rare but it is substantial enough for the FDA to include it as a precaution for taking amoxicillin.
Essentially you can find it in the drug safety data sheet for this antibiotic in the FDA database. Hopefully that is enough proof for you that it can cause enamel discolorations.
How amoxicillin stains teeth
The exact tooth staining mechanism for how amoxicillin causes it, has not been proven or verified. It does not appear to be an issue of great importance since no studies have been done identify the etiology.
We do have a theory on how this antibiotic causes stains to form on your teeth.
Our theory: Amoxicillin molecules can be positively charged while staining dyes are negatively charged. Therefore, if the antibiotic is coating the surfaces of the enamel, it will attract stains to it thus resulting in discoloration.
The basis for our theory draws inspiration from how chlorhexidine mouthwash causes stains on teeth.
Chlorhexidine is an antibiotic oral rinse so they both fall in the same category.
It is also positively charged and studies have demonstrated that it is attracted to negatively charged stains.
It makes perfect sense to us and hopefully someone can conduct a study to prove our theory. We're in clinical practice and not in clinical research so we wouldn't be the ones to do it!
After all, we did find a study which said that amoxicillin can be positively charged.
The greatest risk factor for acquiring stains from amoxicillin use would be if you took the liquid formulations of it. Children are also at higher risk since they may not be able to swallow the large pills so doctors often prescribe it to them in liquid form.
Children since they have trouble taking pill formulations
The concerns for this condition happening in adults should be negligible because most dentists prescribe the tablet or capsule forms of it. Since these formulations have no liquid in them, the antibiotic will have no chance of coming into contact with the teeth and causing the staining to begin with.
How to remove amoxicillin stains from teeth
You can remove amoxicillin stains from teeth with adequate oral hygiene and professional dental cleanings. Yes, that means these stains are not permanent because they are removable.
As a matter of fact, this type of antibiotic staining is of the extrinsic type, which means they are surface stains. They are located on the external surface of the enamel so they will be susceptible to mechanical removal via whitening toothpaste abrasives or scaling by your dentist.
How to get rid of the stains:
Adequate brushing. Diligent brushing with a whitening toothpaste will be adequate for stain removal as per the FDA. Although if you wanted to increase the efficacy, using a peroxide based toothpaste will remove it more efficiently.
Teeth cleaning. If you're really having trouble getting the staining off of your teeth, a professional dental cleaning with a dentist or hygienist will surely get rid of it.
Is teeth bleaching necessary for removal?
Since this tooth staining from amoxicillin is of extrinsic origins and not from intrinsic origins, teeth whitening is unnecessary. You do not need to chemically bleach your teeth in order to get rid of the discoloration.
However, if you wanted to bleach them whiter, you may do so because it would certainly help. Although if you wanted to know if it was absolutely necessary, the answer is no. Only intrinsic stains definitively require chemical bleaching with hydrogen peroxide based products.
Preventing tooth discoloration
Teeth stains from amoxicillin use can be prevented or minimized with good oral hygiene and routine dental visits. These stains can be managed at home since they are of extrinsic origins which means they are located on the surface of the enamel.
Essentially they are susceptible to removal via mechanical means (brushing and cleanings).
How to prevent the stains from forming:
Brush twice daily with a whitening toothpaste. It is even more effective and efficient if you use a whitening toothpaste that contains hydrogen peroxide.
Try to brush after taking the medication. Ideally if you can brush your teeth after taking the antibiotic, you will be able to drastically reduce the chances of it staying on your teeth.
Regular dental cleanings. If you're unable to remove it at home, seeing your dentist would be the next best option.
Once again, we wish to reiterate that the risk is a lot higher if you're taking the liquid forms of amoxicillin. If you're taking the pill form of it, you most likely don't need to worry about any discolorations happening.
Personally, we've always prescribed the pill form of it and we've never had a single complaint about it staining our patients' teeth.