Examples

Methotrexate is typically given by injection. Two injection sites are sometimes used to administer one dose. This method increases absorption of all of the medicine.

How It Works

Methotrexate stops the growth of rapidly dividing cells, such as embryonic, fetal, and early placenta cells.

Methotrexate treatment can be given as a single shot or as several injections. If an ectopic pregnancy continues after 2 or 3 doses of methotrexate, surgical treatment is needed to remove the ectopic pregnancy.

During the week that you have methotrexate injections, your pregnancy hormone levels (human chorionic gonadotropin, or hCG) are tested several times. Your doctor will look for a drop in hCG levels, which is a sign that the pregnancy is ending (hCG levels sometimes rise during the first few days of treatment, then drop).

• If your hCG levels have dropped enough after 1 week, you are then tested on a weekly basis until they are low enough to suggest that the pregnancy has safely ended. This usually takes about a month but can take more than 3 months.
• If your hCG levels aren't dropping enough after 1 week, you will be given another dose of methotrexate. Your hCG levels will be watched as they were after the first dose.
• If your hCG levels continue at higher levels, or if your doctor becomes concerned about tubal rupture, surgery will be needed to remove the ectopic growth.

Methotrexate series. Although it is an uncommon practice, methotrexate can be given every other day until pregnancy hormone (hCG) blood tests confirm that the pregnancy has ended. On alternate days, a medicine called leucovorin (folinic acid) is given by injection to decrease methotrexate side effects. Treatment time for a methotrexate series varies from case to case but can take a month or longer.

Why It Is Used

Methotrexate can be used to:

• End an early ectopic pregnancy.
• Prevent the growth of any embryonic or fetal cells that are left behind after surgery to end an ectopic pregnancy.

It is also used to treat certain types of cancer, rheumatoid arthritis, and as part of an induced abortion.

How Well It Works

Methotrexate works as well as surgery (salpingotomy) for treating an ectopic pregnancy when:¹

• You have low pregnancy hormone (hCG) levels (less than 5,000).
• The embryo has no heart activity.
• The ectopic pregnancy is small with no tubal rupture or bleeding.

Side Effects

All medicines have side effects. But many people don't feel the side effects, or they are able to deal with them. Ask your pharmacist about the side effects of each medicine you take. Side effects are also listed in the information that comes with your medicine. Severe side effects from methotrexate are most likely to develop with long-term use, such as when it is used for cancer treatment.

Callor other emergency services right away if you have:

• Trouble breathing.
• Hives.
• Swelling of your face, lips, tongue, or throat.

Call your doctor if you have:

• Severe pain in your belly or pelvis.
• Bloody vomit.
• Signs of unusual bleeding or bruising, such as black and tarry stools or blood in the urine.
• Sores in the mouth or on the lips.

Common side effects include:

• Mild abdominal (belly) pain. Cramping belly pain is the most common side effect. It usually occurs during the first 2 to 3 days of treatment.
• Vaginal bleeding or spotting.
• Nausea, vomiting, and indigestion.
• Fatigue, lightheadedness, or dizziness.

Rare side effects include:

• Skin sensitivity to sunlight.
• Inflammation of the membrane covering the eye.
• Sore mouth and throat.
• Temporary hair loss.
• Severe low blood counts (bone marrow suppression).
• Inflammation of the lung (pneumonitis).

Because of the risk of side effects, methotrexate treatment requires close medical supervision by a doctor who is experienced with this medicine. During methotrexate treatment, keep your doctor informed of any symptoms that you have.

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

You will be advised to avoid the following until your treatment has finished:

• Vitamins containing folic acid, including prenatal vitamins.
• Alcohol.
• Penicillin.
• Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen. If you are treated with methotrexate, talk to your doctor before using NSAIDs.

Checkups

Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.

Complete the new medication information form (PDF)(What is a PDF document?) to help you understand this medication.

References

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