Ingredient review

Methotrexate

INCI: METHOTREXATE

Methotrexate is a potent prescription drug, not a cosmetic ingredient, and should never be used in skincare products.

beautypharmaceuticalprescription-drug

In plain English

Methotrexate is a strong medication that doctors prescribe for serious conditions like severe psoriasis, rheumatoid arthritis, and some cancers. It works by slowing down cell growth and calming the immune system. Because it can cause serious side effects, it is not allowed in any cosmetic or over-the-counter skincare product. You should never use a product containing methotrexate without a doctor's supervision.

Review score

Safety, usefulness, and evidence

1.0Very Poor
1.0/ 5

Higher-caution ingredient

The evidence base is relatively strong for its common cosmetic role.

Main practical flags: irritation is high; clogging risk is low.

Source
synthetic
Evidence
strong
Irritation
high
Clogging risk
low
How reviews are scored

Quick decision guide

Read the cautions before using

Methotrexate can be useful, but watch for high irritation potential.

Plain-English read

Treat this as a practical screening step before you compare products that contain this ingredient.

  1. Step 1Start with the score, then check the irritation and clogging risk before judging Methotrexate.
  2. Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
  3. Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.

Score terms in plain English

Irritation risk

high

More likely to cause dryness, stinging, peeling, or reactivity if used too aggressively.

Clogging risk

low

Less likely to feel heavy or contribute to clogged pores for most skin types.

Evidence level

strong

There is a stronger practical or research basis for the ingredient role described here.

What it is

Methotrexate is a synthetic drug that belongs to a class of medications called antimetabolites. It was originally developed for cancer treatment and is now also used at lower doses for autoimmune and inflammatory conditions. It is not a cosmetic ingredient and is strictly regulated as a prescription medicine.

How it works

In a medical context, methotrexate works by blocking an enzyme called dihydrofolate reductase, which is needed for cells to make DNA. This slows down the rapid growth of certain cells, such as skin cells in psoriasis or immune cells in rheumatoid arthritis. In cosmetics, it has no legitimate function and is considered unsafe for topical use without medical oversight.

Pros

Effective for severe conditions

When used under medical supervision, methotrexate can significantly improve severe psoriasis and rheumatoid arthritis, reducing symptoms and improving quality of life.

Long history of medical use

Methotrexate has been used for decades in medicine, and its benefits and risks are well understood by healthcare professionals.

Cons and cautions

Not a cosmetic ingredient

Methotrexate is a potent prescription drug with serious side effects. It is not approved for use in any cosmetic or over-the-counter skincare product.

High risk of toxicity

Even small amounts absorbed through the skin can cause liver damage, lung inflammation, and bone marrow suppression. This makes it dangerous for unregulated cosmetic use.

Best for

  • Patients with severe psoriasis under a doctor's care
  • Individuals with rheumatoid arthritis or certain cancers as prescribed

Use caution if

  • Anyone without a prescription from a licensed healthcare provider
  • Pregnant women or those planning pregnancy (can cause birth defects)
  • People with liver disease, kidney disease, or blood disorders

Usage tips

Never use methotrexate in any skincare product without a doctor's prescription
If you are prescribed methotrexate for a medical condition, follow your doctor's dosing and monitoring instructions exactly
Dispose of any expired or unused methotrexate properly according to pharmacy or local guidelines

Safety summary

Methotrexate is a powerful prescription medication with a narrow safety margin. It can cause serious side effects including liver toxicity, lung damage, and bone marrow suppression. It is not safe for cosmetic use and should only be used under strict medical supervision for approved conditions.

Research notes

Extensive clinical research supports the efficacy of methotrexate for severe psoriasis, rheumatoid arthritis, and certain cancers. However, there is no research supporting its use in cosmetics, and studies highlight significant risks of toxicity even with topical application.

Common label clues

Typical concentration
Not applicable in cosmetics; used in prescription formulations only
Regulatory status
Methotrexate is a prescription-only drug regulated by the FDA and similar agencies worldwide. It is not listed as a permitted cosmetic ingredient in the EU, US, or other major markets. Any cosmetic product containing methotrexate is considered adulterated and illegal.
Common uses
Prescription treatment for severe psoriasis, rheumatoid arthritis, and certain cancers
Environmental note
Methotrexate can be harmful to aquatic life if released into waterways. Proper disposal of unused medication is important to protect the environment.

Good to know

  • Methotrexate is sometimes confused with 'methacrylate' or other cosmetic ingredients, but they are completely different
  • The FDA has not approved methotrexate for cosmetic use, and it is classified as a prescription drug
  • If you see methotrexate listed in a skincare product, do not use it and report it to the FDA

Common questions

What is Methotrexate in beauty products?

Methotrexate is a strong medication that doctors prescribe for serious conditions like severe psoriasis, rheumatoid arthritis, and some cancers. It works by slowing down cell growth and calming the immune system. Because it can cause serious side effects, it is not allowed in any cosmetic or over-the-counter skincare product. You should never use a product containing methotrexate without a doctor's supervision.

What does Methotrexate do in a beauty product?

In a medical context, methotrexate works by blocking an enzyme called dihydrofolate reductase, which is needed for cells to make DNA. This slows down the rapid growth of certain cells, such as skin cells in psoriasis or immune cells in rheumatoid arthritis. In cosmetics, it has no legitimate function and is considered unsafe for topical use without medical oversight.

Is Methotrexate safe for most people?

Methotrexate is a powerful prescription medication with a narrow safety margin. It can cause serious side effects including liver toxicity, lung damage, and bone marrow suppression. It is not safe for cosmetic use and should only be used under strict medical supervision for approved conditions.

Who should be careful with Methotrexate?

Anyone without a prescription from a licensed healthcare provider Pregnant women or those planning pregnancy (can cause birth defects) People with liver disease, kidney disease, or blood disorders

Research sources

Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.