Methotrexate

What is Methotrexate

Methotrexate is a Disease Modifying Anti Rheumatic Drug (DMARD). Originally used as a chemotherapy drug to treat certain kinds of cancer, methotrexate was found to be beneficial in those with inflammatory arthritis and/or psoriasis. It may be taken by mouth or via injection.

FDA approved:

December 1953

Average annual cost:

$605.86 – 17.5mg orally per week

Brand Names and International Availability:

Abitrexate (US); Biotrexate (India); Brimexate (Italy); Canceren (Korea); Emthexat (Sweden); Emthexate (Netherlands, Belgium, Norway, Portugal, Spain, Greece, Hong-Kong, Philippines, Taiwan, Thailand, Korea, Israel); Farmitrexat (Germany, Indonesia); Farmotrex (Denmark); Folex (US); Lantarel (Germany); Ledertrexate (Australia, New-Zealand, Netherlands, Belgium, France, Portugal, Finland, Mexico); Maxtrex (England, Philippines); Mexate (Philippines); Metex (Germany); Methoblastin (Australia, New-Zealand); Methotrexate (Australia, Peru, Japan, Hong-Kong, Indonesia, Malaysia, Philippines, Taiwan, Thailand, South-Africa, Israel, US); Methotrexato (Argentina); Metotrexato (Colombia); Mexate (US); MTX (Malaysia, Korea); Neotrexate (India); Rheumatrex (US); Texate (Mexico); Texate-T (Mexico); Tremetex; Trexan (Finland, Taiwan); Trixilem (Mexico); Xaken (Mexico);

 

How does it work?

It is not known exactly how methotrexate works in inflammatory arthritis. It is suspected the benefit comes from its effect on the immune system.

Dosage:

Methotrexate tablets are available in 2.5mgs. Usual dosage is 7.5mg �20mg weekly. Higher doses may be used to treat more severe cases and psoriasis.

How should I take it?

When used for the treatment of rheumatic diseases and psoriasis, methotrexate is almost always taken ONCE A WEEK. Oral methotrexate may be taken with or without food. Injectable methotrexate may usually be self injected after proper instruction from a health care professional.

Contraindications:

Methotrexate is known to cause miscarriages. DO NOT take methotrexate if you suspect you may be pregnant. Pregnancy should be avoided if either partner is receiving methotrexate.

Methotrexate should be avoided in nursing mothers.

Methotrexate should be avoided in those with a history of liver disease.

Drug Interactions:

Oral antibiotics such as tetracycline may decrease the absorption of methotrexate.

The potential for liver damage is increased with the use of alcohol while on methotrexate. Alcohol should be avoided.

Because of the potent nature of this medicine, be sure to tell your doctor about any other medicines you are taking, including nonprescription medicines and vitamins.

Possible side effects:

These side effects are not considered serious but are certainly annoying for those experiencing them.

The most frequently reported side effects include fatigue, nausea, headache, dizziness, diarrhea, mouth sores, increased sensitivity to the sun, loss of appetite, �brain fog�, mood alterations, and hair loss. Many of these side effects are more noticeable the day of and the day following your weekly dose. Many people have found that taking methotrexate before bed allows them to sleep through many of annoying symptoms. These side effects may decrease over time. The severity of these side effects may be decreased by taking oral folic acid supplements.

More serious side effects that you should report right away include dry non-productive cough, fever, black stools, unusual bleeding or bruising, vomiting, persistent sore throat, and yellow skin or eyes.

Methotrexate has the potential to cause liver damage, lung disease and bone marrow suppression. Although usually seen with higher doses than used to treat rheumatic diseases, these can occur with low, weekly doses.

Signs of a possible allergic reaction are rash, swelling and difficulty breathing. These symptoms should be reported immediately.

Precautions & Special Notes:

Due to the potential for sun sensitivity exposure to direct sunlight should be avoided. If you are in the sun please wear protective clothing and strong sun block.

You will be required to have frequent blood work while on this medication. It is very important that you keep all lab and doctor’s appointments.

Never stop the use of methotrexate unless instructed by your physician.

Avoid the use of alcohol while on this drug.

Unless instructed otherwise, make sure you drink plenty of water the day before and after your weekly dose.

You may want to schedule your dose on a day when you have no plans for the next day, until you find out exactly how you react to the drug.

Methotrexate suppresses the immune system. Avoid exposure to illnesses and viruses when possible.

For more information:

RxList Methotrexate
MedicineNet Methotrexate
Pharm Info Net Methotrexate

References:
Mosby’s GenRx®, 10
th ed. Copyright © 2000 Mosby, Inc.

Complete Guide to Prescription and Nonprescription Drugs, H. Winter Griffith, M.D. , Copyright © 1997
RxList.com