Skip to main content


After high dose methotrexate for leukemia


Course# _______________  Date _______________

Please refer to Methotrexate and Leucovorin with High Dose Methotrexate (HDMTX) to learn about side effects and special instructions.

Liquid intake

After receiving high dose methotrexate, it is important that your child stays well hydrated. For this reason, your child will receive IV fluids by a portable pump for at least 3 days after receiving high dose methotrexate. The amount of fluid given is based on your child’s size and how well she tolerates each course of methotrexate. The amount of fluid given may change with future courses of methotrexate.

If your child has repeated vomiting or diarrhea, or if she has a fever while away from the hospital during the 72 hours after high dose methotrexate, call the doctor or clinical pharmacist. Your child may need extra IV fluids to replace the fluids lost from the diarrhea or vomiting.


The same day that the high dose methotrexate is given, your child should start taking a medicine called mercaptopurine, also called 6-MP.  Mercaptopurine is taken by mouth every day for 14 days. For more information, see Mercaptopurine.

Methotrexate blood levels

After high dose methotrexate is given, the laboratory will check your child’s methotrexate blood levels. You must return for methotrexate blood level tests as follows:

Hour __________ on _________________________

Hour __________ on _________________________

at _________________________

at _________________________

After each blood level sample is taken, you must remain at the hospital until your child is seen by a clinical pharmacist. This staff member will tell you:

  • if your child’s methotrexate blood level is normal or high;
  • if your child needs to keep receiving IV fluids or not;
  • if the leucovorin dose and schedule has changed; and
  • if your child needs to have more methotrexate blood levels checked.


Leucovorin is the rescue medicine for high dose methotrexate. Your child will always take leucovorin after receiving high dose methotrexate.

Leucovorin works best when a constant amount is in the body. To keep this amount constant, your child must take this medicine at the scheduled times. Do not miss any leucovorin doses. If your child does miss a dose, call the clinical pharmacist or doctor right away so you can be told how to make up the dose.

If your child vomits within one (1) hour of taking leucovorin by mouth, give another dose of leucovorin. If she vomits within one (1) hour of taking the repeated dose of leucovorin, call the clinic right away. The clinic can arrange for your child to receive leucovorin by IV.

Your child should take the leucovorin at the scheduled time even if her methotrexate blood level sample is not taken at the scheduled time.

Store the IV form of leucovorin in the refrigerator, out of the reach of children.

Leucovorin dosing

One (1) dose of leucovorin should be given ___________ (route: IV or by mouth) every 6 hours for a total of 6 doses at the following dates and times:

Date ________________ Dose #1

Date ________________ Dose #2

Date ________________ Dose #3

Date ________________ Dose #4

Date ________________ Dose #5

Date ________________ Dose #6

Route _______________ Time ____________________

Route _______________ Time ____________________

Route _______________ Time ____________________

Route _______________ Time ____________________

Route _______________ Time ____________________

Route _______________ Time ____________________

The dose, scheduled times, and length of leucovorin therapy is based on your child’s methotrexate blood level. If her methotrexate blood level is high, the clinical pharmacist or doctor will tell you about changes with the leucovorin therapy, and when your child should have another methotrexate blood level check.

If you have questions about your child’s methotrexate blood levels or leucovorin, please call 901-595-3300 and ask the operator to page the on-call clinical pharmacist.

To learn more about the medicines described here, talk to your child’s doctor, clinical pharmacist, or nurse. If you are inside the hospital, dial 0. Locally, call 595-3300. If you are outside the Memphis area, dial toll-free 1-866-2STJUDE (1-866-278-5833), and once you are connected, press 0.


This document is not intended to take the place of the care and attention of your personal physician or other professional medical services. Our aim is to promote active participation in your care and treatment by providing information and education. Questions about individual health concerns or specific treatment options should be discussed with your physician.

St. Jude complies with health care-related federal civil rights laws and does not discriminate on the basis of race, color, national origin, age, disability, or sex.

ATTENTION: If you speak another language, assistance services, free of charge, are available to you. Call 1-866-278-5833 (TTY: 1-901-595-1040).

ATENCIÓN: si habla español, tiene a su disposición servicios gratuitos de asistencia lingüística. Llame al 1-866-278-5833 (TTY: 1-901-595-1040).

تنبيه: إذا كنت تتحدث باللغة العربية فيمكنك الاستعانة بخدمات المساعدة اللغوية المتوفرة لك مجانا. .يرجى الاتصال بالرقم. 5833-278-866-1  (الهاتف النصي: 1040-595-901-1).