Review: could Methotrexate cause Progressive Multifocal Leukoencephalopathy?


Progressive multifocal leukoencephalopathy is found among people who take Methotrexate, especially for people who are female, 60+ old , have been taking the drug for 5 - 10 years, also take medication Mabthera, and have Rheumatoid arthritis . We study 197,008 people who have side effects while taking Methotrexate from FDA and social media. Among them, 310 have Progressive multifocal leukoencephalopathy. Find out below who they are, when they have Progressive multifocal leukoencephalopathy and more.

Personalized health information

On eHealthMe you can find out what patients like me (same gender, age) reported their drugs and conditions on FDA and social media since 1977. Our tools are free and anonymous. 86 million people have used us. 300+ peer-reviewed medical journals have referenced our original studies. Start now >>>


Methotrexate has active ingredients of methotrexate sodium. It is often used in rheumatoid arthritis. (latest outcomes from Methotrexate 212,455 users)

Progressive Multifocal Leukoencephalopathy

Progressive multifocal leukoencephalopathy (rapidly progressive neuromuscular disease caused by opportunistic infection of brain cells) has been reported by people with multiple sclerosis, relapsing-remitting multiple sclerosis, chronic lymphocytic leukaemia, non-hodgkin's lymphoma, rheumatoid arthritis (latest reports from 7,273 Progressive multifocal leukoencephalopathy patients).

On Oct, 17, 2016

197,008 people reported to have side effects when taking Methotrexate.
Among them, 310 people (0.16%) have Progressive Multifocal Leukoencephalopathy

Number of reports submitted per year:

Could Methotrexate cause Progressive multifocal leukoencephalopathy?

Time on Methotrexate when people have Progressive Multifocal Leukoencephalopathy *:

  • < 1 month: 8.33 %
  • 1 - 6 months: 25.0 %
  • 6 - 12 months: 18.75 %
  • 1 - 2 years: 2.08 %
  • 2 - 5 years: 12.5 %
  • 5 - 10 years: 29.17 %
  • 10+ years: 4.17 %

Gender of people who have Progressive Multifocal Leukoencephalopathy when taking Methotrexate *:

  • female: 65.9 %
  • male: 34.1 %

Age of people who have Progressive Multifocal Leukoencephalopathy when taking Methotrexate *:

  • 0-1: 0.0 %
  • 2-9: 0.74 %
  • 10-19: 6.64 %
  • 20-29: 2.58 %
  • 30-39: 5.9 %
  • 40-49: 18.45 %
  • 50-59: 22.51 %
  • 60+: 43.17 %

Top conditions involved for these people *:

  • Rheumatoid Arthritis (134 people, 43.23%)
  • Tonsil Cancer (20 people, 6.45%)
  • Systemic Lupus Erythematosus (20 people, 6.45%)
  • Polymyositis (15 people, 4.84%)
  • Dermatomyositis (14 people, 4.52%)

Top co-used drugs for these people *:

  • Mabthera (67 people, 21.61%)
  • Rituximab (62 people, 20.00%)
  • Prednisone (61 people, 19.68%)
  • Folic Acid (52 people, 16.77%)
  • Cyclophosphamide (48 people, 15.48%)

Top other side effects for these people *:

  • Jc Virus Infection (31 people, 10.00%)
  • Pneumonia (23 people, 7.42%)
  • Lymphopenia (18 people, 5.81%)
  • Drug Ineffective (18 people, 5.81%)
  • Aphasia (18 people, 5.81%)

* Approximation only. Some reports may have incomplete information.

** Reports from social media are used.

How to use the study: print a copy of the study and bring it to your health teams to ensure drug risks and benefits are fully discussed and understood.

Do you have Progressive multifocal leukoencephalopathy when taking Methotrexate?

Browse all side effects of Methotrexate

a b c d e f g h i j k l m n o p q r s t u v w x y z

Drugs that are associated with Progressive multifocal leukoencephalopathy

Progressive multifocal leukoencephalopathy

Could your condition cause Progressive multifocal leukoencephalopathy

Progressive multifocal leukoencephalopathy

Related studies

Can you answer these questions?

More questions for: Methotrexate, Progressive multifocal leukoencephalopathy

You may be interested in these reviews

More reviews for: Methotrexate, Progressive multifocal leukoencephalopathy

NOTE: The study is based on active ingredients and brand name. Other drugs that have the same active ingredients (e.g. generic drugs) are NOT considered.

WARNING: Please DO NOT STOP MEDICATIONS without first consulting a physician since doing so could be hazardous to your health.

DISCLAIMER: All material available on is for informational purposes only, and is not a substitute for medical advice, diagnosis, or treatment provided by a qualified healthcare provider. All information is observation-only, and has not been supported by scientific studies or clinical trials unless otherwise stated. Different individuals may respond to medication in different ways. Every effort has been made to ensure that all information is accurate, up-to-date, and complete, but no guarantee is made to that effect. The use of the eHealthMe site and its content is at your own risk.

You may report adverse side effects to the FDA at or 1-800-FDA-1088 (1-800-332-1088).

If you use this eHealthMe study on publication, please acknowledge it with a citation: study title, URL, accessed date.