Methotrexate Injection: Uses, Dosage, Side Effects, Precautions and Alternates

Quick overview

Methotrexate Injection (generic name: methotrexate) is a prescription antimetabolite medicine given into a muscle, vein, under the skin, or into the fluid around the spinal cord. It is used to treat certain cancers and, at lower doses, to calm an overactive immune system in conditions like rheumatoid arthritis and psoriasis. It works by blocking a substance the body needs to make new cells, which slows cancer cell growth at higher doses or reduces inflammation at lower doses.

What is Methotrexate Injection

Methotrexate injection is a prescription medicine given into a muscle, vein, under the skin, or into the fluid around the spinal cord. It is used to treat certain cancers and, at lower doses, to calm an overactive immune system in conditions like rheumatoid arthritis and psoriasis.

Methotrexate Injection uses

• Treats certain types of acute lymphocytic leukemia (ALL) in adults and children
• Treats or prevents meningeal leukemia (cancer in the covering of the spinal cord and brain)
• Treats certain types of non-Hodgkin's lymphoma
• Treats osteosarcoma (bone cancer) after surgery to remove the tumor
• Treats cutaneous T-cell lymphoma (CTCL)
• Treats breast cancer in adults
• Treats certain cancers of the head and neck in adults
• Treats gestational trophoblastic tumors in adults
• Treats rheumatoid arthritis in adults
• Treats polyarticular juvenile idiopathic arthritis in children
• Treats severe psoriasis in adults
• Sometimes used for bladder cancer, Crohn's disease, and other autoimmune diseases

Benefits of Methotrexate Injection

• Slows the growth of cancer cells
• Slows the growth of skin cells to reduce psoriasis scaling
• Reduces immune system activity to ease joint pain and swelling in rheumatoid arthritis
• Early treatment of rheumatoid arthritis can help reduce further joint damage and preserve joint function

How Methotrexate Injection works

Methotrexate blocks a substance the body needs to make new cells. At low doses this calms an overactive immune system and reduces inflammation; at higher doses it slows or stops the growth and spread of cancer cells.

Methotrexate Injection dosage

Methotrexate injection is given into a muscle, into a vein, under the skin, or into the fluid around the spinal cord by a healthcare professional. How often you receive it depends on your condition and how your body responds.

For rheumatoid arthritis, polyarticular juvenile idiopathic arthritis, or severe psoriasis, this medicine is taken only once a week on the same day each week, not every day — taking it daily instead of weekly has caused deaths.

If you are taking methotrexate for an autoimmune condition, your doctor may have you take a folic acid or folinic acid supplement to help reduce side effects such as mouth sores. If you are taking methotrexate for cancer, do not take folic acid or folinic acid unless your doctor tells you to, since it may make treatment less effective.

Continue your normal diet unless your doctor tells you otherwise. Call your doctor right away if you cannot keep an appointment to receive this medicine.

Available forms and strengths

• Injection (intramuscular, intravenous, subcutaneous, or intrathecal)
• Powder to be mixed with liquid for injection
• Tablets
• Oral solution

Side effects of Methotrexate Injection

Common

• Joint or muscle pain
• Reddened eyes
• Swollen gums
• Hair loss
• Nausea, stomach pain, upset stomach
• Tiredness, feeling unwell, fever, chills
• Mouth sores
• Abnormal liver function tests
• Burning skin lesions
• Being more sensitive to light

Serious

• Vomiting
• Blurred vision or sudden loss of vision
• Sudden fever, severe headache, and stiff neck
• Seizures
• Confusion or memory loss
• Weakness or difficulty moving one or both sides of the body
• Difficulty walking or unsteady walking
• Loss of consciousness
• Impaired speech
• Decreased urination
• Swelling of the face, arms, hands, feet, ankles, or lower legs
• Signs of infection such as sore throat, chills, fever, or ongoing cough
• Unusual bruising or bleeding
• Unusual tiredness or weakness, pale skin, shortness of breath
• Mouth sores, diarrhea, black, tarry, or bloody stools, vomiting (especially bloody or coffee-ground-like)
• Dry cough, fever, or shortness of breath
• Nausea, extreme tiredness, loss of appetite, pain in the upper right stomach, yellowing of the skin or eyes, flu-like symptoms
• Rash, itching, hives, throat tightness, swelling of the face, lips, tongue, or throat, or trouble swallowing
• Fever, rash, blisters, or peeling skin
• Development of new cancers, including lymphoma

Warnings and precautions

• Methotrexate can cause a serious, life-threatening allergic reaction during or shortly after the injection. Tell your doctor right away about rash, itching, hives, throat tightness, facial swelling, trouble swallowing, dizziness, trouble breathing, chest pain, wheezing, or feeling faint.
• Taking methotrexate the wrong way (daily instead of weekly for arthritis or psoriasis) has caused deaths. Always use the correct dose for your condition.
• Methotrexate can lower your blood cell counts, raising the risk of infection, bruising, bleeding, and anemia.
• Methotrexate can cause lung damage; tell your doctor if you have lung disease.
• Methotrexate can damage the lining of the mouth, stomach, or intestines, especially in people with stomach ulcers or ulcerative colitis.
• Using methotrexate may increase the risk of developing lymphoma.
• Methotrexate can cause serious or life-threatening skin reactions such as blistering or peeling skin.
• Methotrexate can weaken the immune system, increasing the risk of serious infections.
• Do not receive live vaccines during treatment without talking to your doctor first.
• If given with radiation therapy, methotrexate may increase the risk that radiation will damage your skin, bones, or other body parts.
• Methotrexate can make your skin more sensitive to sunlight; avoid prolonged sun or tanning bed exposure and use sun protection.
• Methotrexate can harm or cause death to an unborn baby and must not be used during pregnancy for arthritis or psoriasis. Women need a pregnancy test before starting and should use reliable birth control during treatment and for 6 months after the last dose; men should use reliable birth control during treatment and for 3 months after the last dose.
• Do not breastfeed while receiving methotrexate and for at least 1 week after your final dose.
• Tell your doctor if you have kidney disease or are on dialysis, as this may increase the risk of serious side effects and your dose may need to be adjusted or treatment stopped.
• Methotrexate may cause liver damage, especially with long-term use. Tell your doctor about any history of heavy alcohol use or liver disease. Risk may be higher if you are elderly, obese, or have diabetes.
• Ask your doctor about safe alcohol use during treatment, since drinking alcohol can increase the risk of liver damage.
• Methotrexate may cause dizziness or drowsiness. Do not drive a car or operate machinery until you know how this medication affects you.

Storage

• Store methotrexate at room temperature away from moisture, heat, and light
• Keep the tablets away from light and out of the reach of children
• Do not flush medications down the toilet or pour them into a drain unless instructed to do so
• Properly discard this product when it is expired or no longer needed; consult your pharmacist or local waste disposal company

When to see a doctor

• Call your doctor immediately if you notice signs of infection such as sore throat, chills, fever, or ongoing cough, or unusual bruising, bleeding, tiredness, pale skin, or shortness of breath.
• Call your doctor immediately if you have nausea, extreme tiredness, loss of appetite, pain in the upper right stomach, yellowing of skin or eyes, or flu-like symptoms, which could signal liver problems.
• Call your doctor immediately if you develop dry cough, fever, or shortness of breath, which could indicate lung damage.
• Call your doctor immediately if you have mouth sores, diarrhea, black or bloody stools, or vomiting (especially bloody or coffee-ground-like).
• Call your doctor immediately if you develop fever, rash, blisters, or peeling skin.
• Tell your doctor immediately if you or your partner become pregnant while using this medicine.
• If overdose symptoms appear, such as collapse, seizure, trouble breathing, or inability to wake, seek emergency care immediately; otherwise call a poison control center.

Alternatives

• Hydroxychloroquine
• Azathioprine
• Sulfasalazine