Medically Reviewed on 10/4/2022

Generic Name: fluoride

Brand and Other Names: Luride, Karidium, Fluoritab, Pediaflor, sodium fluoride

Drug Class: Minerals, Other

What is fluoride, and what is it used for?

Fluoride, or sodium fluoride, is an inorganic chemical compound used to prevent dental caries and maintain dental health.

Dental caries are cavities that form in teeth because of damage from the acid produced when bacteria metabolize sugars. Severe dental caries can cause pain, infection, and abscesses that may require tooth extraction. Fluoride protects the enamel and dentin from erosion caused by the acid.

Fluoride works in two ways to protect teeth from caries. Fluoride kills caries-causing bacteria such as Streptococcus mutans and lactobacilli by inhibiting enzymes essential for bacterial metabolism. Fluoride changes the permeability of cell membranes, lowering the pH in the cellular fluid (cytoplasm), and reducing the acidity that erodes the tooth enamel and causes tooth decay. When the surface of hydroxyapatite crystals on the teeth absorbs fluoride, it develops resistance to demineralization by the acid.

The principal source of fluoride is drinking water, and fluoride is commonly used as an ingredient in toothpaste and other dental products. Fluoride is also available as oral tablets and lozenges that can be taken as a supplement if the fluoride levels in water are inadequate for daily recommended intake. In addition to fluoride, it is also important to reduce the intake of sugars and maintain good oral hygiene to prevent dental caries.


  • Do not take fluoride supplementation if:
    • You are hypersensitive to fluoride, tartrazine, or any component in the formulation
    • You are on a low-sodium or sodium-free diet
    • Fluoride content in drinking water is greater than 0.7 ppm
  • Cautions for fluoride use in children:
    • Do not use the 1 mg tab in children below 3 years of age or when drinking water has more than 0.3 ppm fluoride
    • Do not use the 1 mg/5 mL rinse in children below 6 years of age
  • Prolonged ingestion of high doses of fluoride can cause tooth discoloration (dental fluorosis).
  • Do not administer fluoride to children below 6 months old.
  • Some formulations may contain propylene glycol which can be toxic in large amounts.

What are the side effects of fluoride?

Common side effects of fluoride include:

  • Skin rash
  • Hypersensitivity reaction
  • Nausea
  • Vomiting
  • Temporary dental discoloration (with products containing stannous fluoride)

Call your doctor immediately if you experience any of the following symptoms or serious side effects while using this drug:

This is not a complete list of all side effects or adverse reactions that may occur from the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may also report side effects or health problems to the FDA at 1-800-FDA-1088.


What causes tooth decay? See Answer

What are the dosages of fluoride?

Strength expressed as fluoride ion


  • 0.25 mg
  • 0.5 mg
  • 1 mg

Oral Liquid

  • 0.125 mg/drop

Tablet, Chewable

  • 0.25 mg
  • 0.5 mg
  • 1 mg


  • 1 mg


Dental Caries Prevention

  • Intake typically achieved from drinking tap water (community levels vary)
  • Males adequate intake: 4 mg/day
  • Females adequate intake: 3 mg/day
  • Upper limit:10 mg/day

Otosclerosis (Off-label)

  • 20-120 mg sodium fluoride/day divided three times daily orally, usually 20-40 mg/day

Osteoporosis (Off-label)

  • 30-100 mg sodium fluoride/day orally


Dental Caries Prevention

Adequate Intake

Dosing depends on local fluoride content of water supply

Water less than 0.3 ppm F ion

  • Birth - 6 months: None
  • 6 months - 3 years: 0.25 mg orally every day
  • 3-6 years: 0.5 mg orally every day
  • 6-16 years: 1 mg orally every day

Water 0.3-0.6 ppm F ion

  • Birth - 6 months: None
  • 6 months - 3 years: None
  • 3-6 years: 0.25 mg orally every day
  • 6-16 years: 0.5 mg orally every day

Water more than 0.6 ppm F ion

  • All ages: Supplementation not required

Dose Consideration

  • The potential toxic dose for children below 6 years: 8 mg/kg
  • 1 ppm = 1 mg fluoride ion
  • 2.2 mg sodium fluoride contains 1 mg fluoride ion


What drugs interact with fluoride?

Inform your doctor of all medications you are currently taking, who can advise you on any possible drug interactions. Never begin taking, suddenly discontinue, or change the dosage of any medication without your doctor’s recommendation.

  • Fluoride has no known severe, serious or moderate interactions with other drugs.
  • Mild Interactions of Fluoride include:
    • molybdenum

The drug interactions listed above are not all of the possible interactions or adverse effects. For more information on drug interactions, visit the RxList Drug Interaction Checker.

It is important to always tell your doctor, pharmacist, or health care provider of all prescription and over-the-counter medications you use, as well as the dosage for each, and keep a list of the information. Check with your doctor or health care provider if you have any questions about the medication.

Pregnancy and breastfeeding

  • Animal reproductive studies do not show evidence of fetal harm from fluoride.
  • Recommended levels of fluoride is likely safe during pregnancy, however, excessively fluorinated water should be avoided by pregnant women, because it can cause anemia and may harm the fetus as well.
  • Fluoride in doses below 10 mg per day is safe for use by nursing mothers, for example, quantities found in toothpastes, mouth rinses, and fluoride dental treatments.

What else should I know about fluoride?

  • Take fluoride supplementation exactly as prescribed, do not take excessive doses.
  • Avoid swallowing topical fluoride products.
  • Do not take fluoride supplements if there is adequate intake from fluorinated drinking water.
  • Store safely out of reach of children.
  • In case of overdose, get medical help or contact Poison Control.


Fluoride, or sodium fluoride, is an inorganic chemical compound used to prevent dental caries and maintain dental health. Common side effects of fluoride include skin rash, hypersensitivity reaction, nausea, vomiting, and temporary dental discoloration (with products containing stannous fluoride). Take fluoride supplementation exactly as prescribed. Do not take fluoride supplements if there is adequate intake from fluorinated drinking water.

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You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

Medically Reviewed on 10/4/2022