Otrexup (methotrexate) is a disease-modifying antirheumatic drug (DMARD) that's used for certain autoimmune conditions. It can treat severe rheumatoid arthritis (RA), polyarticular juvenile idiopathic arthritis (pJIA), and severe psoriasis when other treatment options haven't worked well. Otrexup (methotrexate) is available as an autoinjector. The medication is injected under the skin once a week. Side effects include nausea and liver test changes.
Rheumatoid arthritis (RA) in adults
Polyarticular juvenile idiopathic arthritis (pJIA) in children
Psoriasis in adults
Otrexup (methotrexate) is a medication that belongs under the drug class known as antimetabolites. It's also considered a disease-modifying antirheumatic drug (DMARD).
The way Otrexup (methotrexate) works to treat certain types of arthritis and psoriasis isn't fully clear. Research suggests that the medication helps lower the activity of the immune system to lessen inflammation. It might also help slow down the growth of skin cells.
Source:Â DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor or nurse immediately if any of the following side effects occur:
More common
Black, tarry stools
blood in the urine or stools
bloody vomit
joint pain
reddening of the skin
sores in the mouth or lips
stomach pain
swelling of the feet or lower legs
Less common
Back pain
bleeding, blistering, burning, coldness, discoloration of the skin, feeling of pressure, hives, infection, inflammation, itching, lumps, numbness, pain, rash, redness, scarring, soreness, stinging, swelling, tenderness, tingling, or warmth at the injection site
blurred vision
confusion
convulsions (seizures)
cough or hoarseness
dark urine
dizziness
drowsiness
fever or chills
headache
lower back or side pain
painful or difficult urination
pinpoint red spots on the skin
shortness of breath
unusual bleeding or bruising
unusual tiredness or weakness
yellow eyes or skin
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Only need to take once a week
Good option for people who have trouble swallowing pills
Conveniently stored at room temperature
Can make your skin more sensitive to the sun and raise your risk for sunburns
Many serious risks that affect many different parts of the body (e.g., lungs, liver, kidney, skin)
Can't use while pregnant or breastfeeding
Otrexup (methotrexate) is injected once a week. Choose a day of the week that's easy for you to remember. You can also mark your calendar or use a reminder app on your phone so you don't forget. This medication isn't meant to be used every day; otherwise, it could lead to serious and fatal side effects.
Your provider will monitor you closely during treatment because Otrexup (methotrexate) can cause many side effects in different parts of your body. Make sure to get all of your lab tests and scans done on time so your provider can check that the medication is safe for you.
Otrexup (methotrexate) can make you feel dizzy or tired. Be sure you know how this medication affects you before you drive or operate machinery.
Otrexup (methotrexate) can make your skin more sensitive to the sun, raise your risk for sunburns, and even make previous sunburns come back. Try to avoid direct sun exposure. When you go outside, wear sunscreen and clothes that protect your skin. Tell your provider if you get a sunburn or have painful skin while you're taking this medication.
Before you get any vaccines, tell your provider that you're taking Otrexup (methotrexate). Some vaccines (e.g., live vaccines) might not work as well while you're taking this medication. Your providers can make sure the vaccine you're getting is safe for you.
Tips on how to use Otrexup (methotrexate):
Don't try to inject Otrexup (methotrexate) until you've been trained by a healthcare provider. Become familiar with the Instructions for Use, and ask your provider if you have any questions.
The Otrexup (methotrexate) autoinjectors are designed so you can't see the needle. It's normal if you don't see it when you're using the autoinjector, and you'll still get the full dose of your medication.
Before each time you use Otrexup (methotrexate), check that the solution in the viewing window looks yellow and is free of particles. Air bubbles are normal. Otherwise, use another autoinjector device.
Carefully follow the instructions to use the Otrexup (methotrexate) autoinjector device to inject the medication under the skin of your stomach or thigh. You'll know that you've injected the full dose of medication once you see that the viewing window is half blocked with a red flag. Contact your provider or pharmacist if it isn't.
Each Otrexup (methotrexate) autoinjector is meant for one-time use, so don't try to reuse it. After you've used an autoinjector, place it in a special sharps container for disposal. Don't throw it away in the trash. This helps prevent needle-stick injuries.
Otrexup (methotrexate) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Peptic ulcer disease | Ulcerative colitis | Heavy alcohol use | Kidney or liver problems| | Diabetes | Higher doses of Otrexup (methotrexate) | Taking Otrexup (methotrexate) for a long time | Taking NSAIDs | Considered obese | Fluid buildup in the body (e.g., stomach, lungs) | Older age
Otrexup (methotrexate) can cause many serious problems all over the body that can be fatal. It can put stress on your lungs, digestive tract, liver, kidneys, skin, and nervous system.
These problems can happen at any time during treatment, so your provider will follow up with you often. Your provider might also order various lab tests, tissue samples (biopsies), or scans to help check for these problems. Most symptoms can be treated if they're recognized early.
Get medical help right away if you have any of the following symptoms.
Lung problems: trouble breathing, cough
Digestive tract problems: diarrhea, vomiting, stomach pain, mouth pain or inflammation
Liver problems: yellowing of your skin or whites of the eyes, pain in the right side of your stomach, dark urine, vomiting
Kidney problems: swelling in your feet or ankles, little or no urine
Nerve problems: changes in vision, not able to move one side of your body, confusion, seizure
Rarely, Otrexup (methotrexate) can cause life-threatening allergic reactions and skin reactions. Get medical help right away if you have trouble breathing, swelling in your face or throat, rash, blisters, peeling skin, red skin, mouth sores, muscle aches, or fever.
Risk factors: Blood problems | Current infection | Weak immune system
Otrexup (methotrexate) can affect your bone marrow and cause your body to make fewer blood cells. This can cause many side effects. It can raise your chance of bleeding and make you more likely to have anemia and get infections. Your healthcare provider will probably ask to have your blood drawn periodically during treatment to check your blood cell counts. Talk to your provider right away if you suddenly have muscle weakness, unexplained bruising or bleeding, or develop a fever.
Risk factors: Pregnancy
Otrexup (methotrexate) can cause life-threatening harm to an unborn baby if it's taken during pregnancy. For this reason, avoid taking this medication if you're pregnant. If you or your partner can become pregnant, it's important for you to use birth control whenever you have sex during treatment. Continue to avoid becoming pregnant for at least 6 months (for females) and for at least 3 months (for males) after the last dose. Talk to your provider about other options if you become or would like to become pregnant.
It's possible for Otrexup (methotrexate) to make it harder for you to have children (a loss of fertility, or infertility). This medication has been linked to low sperm count and menstrual problems. This might not be reversible, so it's important that you discuss the risks with your healthcare provider if you're considering having children in the future.
Some people who took low-dose methotrexate by mouth developed certain types of cancer and tumors, such as skin cancers and blood cancers. The risk for cancer with Otrexup (methotrexate) can't be ruled out. Tell your provider if you have an unexplained fever, feel very tired, have swollen lymph nodes in your neck or armpits, or spots or moles on your skin that seem unusual.
Taking methotrexate might cause a serious condition called tumor lysis syndrome (TLS) in people who have certain cancers or tumors. Typically, people who are prescribed Otrexup (methotrexate) for arthritis or psoriasis have a low chance of developing TLS unless they have a known or undiagnosed tumor. Call your provider right away if you have nausea, vomiting, low appetite, tiredness, side pain, muscle cramps, a pounding chest, dark urine, or less urination. These can be symptoms of TLS.
Rheumatoid arthritis in adults: The typical starting dose is 7.5 mg injected under the skin once a week.
Polyarticular juvenile idiopathic arthritis in children: The dose is based on body surface area (BSA), which takes into account weight and height. The typical starting dose is 10 mg/m2 injected under the skin once a week.
Psoriasis in adults: The typical starting dose ranges from 10 mg to 25 mg injected under the skin once a week.
Your provider might slowly raise your dose based on how well the medication is working for you.
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are receiving this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Currently pregnant
Liver problems
Weak immune system
Blood problems (e.g., low platelets, low white blood cells, anemia)
Rheumatoid arthritis (RA) in adults
Polyarticular juvenile idiopathic arthritis (pJIA) in children
Psoriasis in adults
Acute lymphoblastic leukemia (ALL) in adults and children; given with other chemotherapy
Cutaneous T-cell lymphoma in adults; given by itself or with other chemotherapy
Advanced non-Hodgkin lymphoma in adults; given with other chemotherapy
Rheumatoid arthritis (RA) in adults
Polyarticular juvenile idiopathic arthritis (pJIA) in children
Severe psoriasis in adults
Rheumatoid arthritis (RA) - adults only
Juvenile idiopathic arthritis (JIA) - people age 2 and older
Psoriatic arthritis (PsA) - adults only
Ankylosing spondylitis (AS) - adults only
Crohn's disease (CD) - people age 6 and older
Ulcerative colitis (UC) - people age 5 and older
Plaque psoriasis - adults only
Hidradenitis suppurativa (HS) - people age 12 and older
Uveitis - people age 2 and older
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Antares Pharma, Inc. (2019). Otrexup (methotrexate) injection, for subcutaneous use [package insert].
Antares Pharma, Inc. (2023). Otrexup- methotrexate injection, solution [package insert]. DailyMed.
Benjamin, O., et al. (2023). Disease-modifying antirheumatic drugs (DMARD). StatPearls.
Czarnecka-Operacz, M., et al. (2014). The possibilities and principles of methotrexate treatment of psoriasis - The updated knowledge. Advances in Dermatology in Allergology.
El-Esawy, F. M., et al. (2022). Methotrexate mechanism of action in plaque psoriasis: Something new in the old view. The Journal of Clinical and Aesthetic Dermatology.
Gupta, A., et al. (2018). Tumor lysis syndrome. Journal of the American Medical Association Oncology.
Hagihara, M., et al. (2018). Methotrexate-associated intravascular large B-cell lymphoma in a patient with rheumatoid arthritis: A very rare case. Internal Medicine.
OrthoInfo. (2022). Juvenile arthritis. The American Academy of Orthopaedic Surgeons.
Yan, M. K., et al. (2022). Association between low-dose methotrexate exposure and melanoma: A systematic review and meta-analysis. Journal of the American Medical Association Dermatology.
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