8 Surprising Methotrexate Dental Side Effects

Do you or a close friend or family member take methotrexate? Are you wondering why there has been a lot of change in your oral health? Well, it could be methotrexate dental side effects.

Methotrexate is classified as an antineoplastic (cancer medicine). It can also be used to treat inflammatory types of arthritis.

It works by interfering with enzymes required for a cell to grow and live.

If you are considering undergoing chemotherapy or using methotrexate for any other reason, this article is for you. So, keep reading for more information on methotrexate dental side effects.

What Is Antineoplastic Drug?

Antineoplastic drugs prevent the growth of abnormal tissue masses that actively increase more than they should or do not die when they should.

Methotrexate’s main target tissues are malignant cells, bone marrow, fetal cells, buccal mucosa, intestinal mucosa, and urinary bladder cells.

What Is the Purpose of Methotrexate?

Methotrexate inhibits the cell’s growth, which leads to eventual cell death. The dead cells are finally destroyed and excreted from the body.

Methotrexate is used to treat breast cancer, epidermoid malignancies of the head and neck, and advanced mycosis fungoides (cutaneous T-cell lymphoma).

In addition, it can also treat lung cancer, particularly squamous and small cell forms.

According to the American Cancer Society (ACS), advanced-stage non-lymphomas such as Hodgkin’s disease are also treated with methotrexate and other chemotherapy drugs.

Methotrexate can be given orally, intramuscularly, intravenously (as a bolus injection or infusion), intrathecally, and intra-arterially.

Here is a list of excipients in methotrexate:

  • Methotrexate sodium
  • Sodium Hydroxide
  • Magnesium Stearate
  • Lactose monohydrate
  • Magnesium Stearate 
  • Starch Pregelatinised
  • Lactose monohydrate

8 Methotrexate Dental Side Effects

Here are 8 common methotrexate dental side effects:

1. It Can Cause Mouth Ulcers

Can you identify oral ulceration if you see one? It is simple since it usually appears yellow, white, or grey, round or oval sore on the tongue, lips, mouth roof, and lips.

Mouth ulcers often appear as a methotrexate dental side effect, especially when under treatment for cancer or benign neoplasms, since it requires high doses.

Experts state that a reduction in folate levels is the leading cause of oral ulceration.

Methotrexate consumption increases how the body breaks down and removes folate as waste. The excess folate breakdown leads to folate deficiency, which has oral ulceration as a symptom.

2. May Lead to Periodontal Disease

Periodontal disease is the inflammation of the tissues holding the teeth.

According to the Centers for Disease Control and Prevention (CDC), periodontal disease affects 47.2% of adults aged 30 and above in the United States.

Low folic acid levels primarily bring on periodontal disease.

The folic acid decrease is among the well-known and predicted methotrexate dental side effects due to a change in how folic acid breaks down. 

3. May Lead to Mucositis

Mucositis, one of the methotrexate dental side effects, is the inflammation and soreness of the gut or mouth as defined.

Mucosal epithelial cells accumulate more methotrexate than bone marrow stem cells during treatment, leading to mucositis development.

Mucositis is painful, but doctors can prescribe medications that will help ease the symptoms.

Some of the symptoms of mucositis include blood in the mouth, burning sensations, pain when eating, bad breath, and a dry mouth.

4. Tooth Decay

Dental caries, also called tooth decay, is the harm brought to the tooth when enamel-eating bacteria in your mouth produce acids that attack the tooth’s surface.

Tooth decay may result in a cavity, or small hole, in the tooth. Dental decay can result in discomfort, infection, pain, and even tooth loss if the symptom is not treated.

5. Infections of the Oral Mucosa

One of the significant methotrexate dental side effects is an infection of the oral mucosa. 

Painful sores or ulcers on the mucous membrane lining are some symptoms of infection of the oral mucosa. Mucosal diseases may affect any mucous membrane.

In addition, methotrexate is associated with Dysphagia, which is having difficulty swallowing food or liquid.

Methotrexate has a tremendous negative impact on the general health of your mouth. Inflammation and damage to the oral cavity make the mouth tissue very sensitive and painful, making swallowing difficult.

6. Changes in Taste

Methotrexate significantly affects the oral cavity, of which the tongue is the central part. Taste buds, which are on different parts of the tongue, are responsible for taste.

The tongue tissues are sensitive and easily damaged by methotrexate.

Damaged tissue on taste buds cannot send the correct information to the brain for taste identification, leading to changes in taste.

7. The Mouth Feels Numb

One of the methotrexate dental side effects is an increased body’s ability to break down folate, an essential nutrient.

Low folate levels brought on by the accelerated breakdown may cause tongue-tingling and numbness.

8. Can Lead to Tooth Loss

Teeth loss is a common methotrexate dental side effect since it affects the gum, which holds the teeth in place. Methotrexate makes the tooth loose, and it may eventually come off.

Other Methotrexate Side Effects

Nausea and vomiting

Gastrointestinal problems are the most common side effect of methotrexate.

Up to 65% of patients with rheumatoid arthritis who are prescribed this medication experience nausea and vomiting.


This is sometimes referred to as methotrexate fog. An “overall blah feeling” also accompanies it.

It can happen after receiving the first dose of the medication. Fatigue improves, especially after the patient’s body gets accustomed to the medication.

Hair loss

It is responsible for hair loss in up to 3% of people. This is because the medication is preventing cellular growth.

Folic acid and biotin supplements can help reduce the chances of hair loss.

If a patient experiences hair loss on the medication, the hair can grow back six months after treatment has stopped.


Patients can take regular painkillers like paracetamol unless otherwise advised by their doctor.

Avoid NSAIDs like aspirin or ibuprofen. Speak with your doctor before taking any over-the-counter painkillers.

Can You Get Dental Work Done While on Methotrexate?

Methotrexate dental side effects are more pronounced in the mouth. The medicine causes your skin to be more sensitive to sunlight and causes wounds to take longer to heal.

Most dental procedures (extractions, veneers, fillings, crowns, root canals, braces, and Invisalign) involve some minor operations. Wounds are prone to infection, further extending the healing period.

It is, therefore, necessary to always consult your doctor before going for any dental work.

What Should You Avoid While Taking Methotrexate?

  • Getting pregnant: Because methotrexate is an antifolate, it can reduce folic acid in your body. Lack of folic acid during pregnancy may result in congenital disabilities in the baby’s brain and spinal cord.
  • Alcohol: Both alcohol and methotrexate affect the liver, so taking alcohol increases the chances of developing liver damage.
  • Excessive sunlight: Methotrexate increases UV sensitivity in places previously sunburnt or exposed to the sun and may cause rashes. A condition referred to as radiation recall.

Important tip: Taking folic acid supplements can help lower methotrexate side effects.


Over the last few years, methotrexate use has increased due to the neoplasm treatment increase.

The increased usage has triggered more research on methotrexate dental side effects.

Previously, methotrexate was used only to treat cancer, but it is now also used to treat rheumatoid arthritis, psoriasis, and Crohn’s disease.

Though methotrexate dental side effects are lower than its benefits, it is important to keep them in mind for adequate preparation and countermeasures.

[related_posts_by_tax posts_per_page="4"]