Methotrexate injection for ectopic pregnancy

The methotrexate injection is given into the muscle of your thigh or bottom.

• The dose of methotrexate will depend on your weight and height.  
• If your pregnancy hormone levels haven't decreased enough after the first dose, another dose of methotrexate may be needed.
• You will have follow-up appointments and blood tests until your hormone levels have returned to normal.

Stomach pain and bleeding

• About 2 to 7 days after the methotrexate injection, you may have stomach cramps.
• You can take paracetamol to help with the pain; you can also try a wheat-pack or hot water bottle.
• Note: Don't use anti-inflammatories (eg, ibuprofen, naproxen, aspirin or diclofenac) as they can affect the way methotrexate works.
• You may have light bleeding similar to a period for a few days, and you may have some brown discharge for a few weeks.

If the pain is severe, if you're bleeding heavily, feeling faint, dizzy, feel hot or have cold chills, go straight to the Emergency Department at the hospital.

Blood tests

You will need regular blood tests to make sure your pregnancy hormone levels are falling.

• You’ll need blood tests on day 4 and day 7 after the methotrexate injection, and then every week, until pregnancy hormone level is no longer detectable.
• On the 7th day after the methotrexate, you will need a blood test to check your full blood count and liver function.

Things to avoid after the methotrexate injection

• Don't take anti-inflammatories eg, ibuprofen (Nurofen), diclofenac (Voltaren), naproxen, or aspirin for one week after treatment because they can affect the way methotrexate works. You can use paracetamol (Panadol) instead.
• Don't have sex or put anything into your vagina until your pregnancy hormone level is no longer detectable.
• Avoid drinking alcohol for 2 weeks as it can interact with methotrexate and cause liver damage.
• Don't take any vitamins, including pregnancy vitamins, or foods that have added folic acid (also called folate) until your blood tests show your hormone levels are normal again.
• Avoid heavy or strenuous exercise for a few weeks.
• Avoid direct sun exposure for 1 month after the methotrexate injection as you will burn more easily. Wear sunscreen.

Contraception

• It's important to avoid getting pregnant for at least 3 months after having the last dose of methotrexate to allow it to completely clear from your body.
• Methotrexate can cause abnormalities to the developing baby if you get pregnant again within 3 months. You must use contraception during this time.

Side effects after methotrexate injection are usually mild and may only last 1 or 2 days. They can include:

• an upset stomach
• nausea (feeling sick) or diarrhoea (runny poos)
• tiredness
• headache
• a sore mouth or mouth ulcers
• sensitivity to sunlight.

In rare cases, methotrexate may cause a rash, cause changes to your kidney or liver blood tests or anaemia. See your doctor if you have a rash or you feel very unwell.

Read more about medicines and side effects and reporting a reaction you think might be a side effect.