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RediTrex (Injection, Subcutaneous)

Generic name: methotrexatemeth-oh-TREX-ate ]
Brand names: Otrexup, Rasuvo, RediTrex

Medically reviewed by Drugs.com. Last updated on Mar 4, 2023.

Subcutaneous route(Solution)

Use only for severe rheumatoid arthritis and psoriasis unresponsive to other therapies. Monitor for bone marrow, liver, lung, skin, and kidney toxicities. Death, fetal death and/or congenital anomalies, and severe sometimes fatal lung disease, tumor lysis syndrome, skin reactions, and Pneumocystis jiroveci pneumonia have been reported. Use not recommended in women of childbearing potential and is contraindicated in pregnant women. Advise females and males of reproductive potential to use effective contraception during and after treatment. Unexpectedly severe (sometimes fatal) bone marrow suppression, aplastic anemia, and gastrointestinal toxicity have been reported with concomitant administration of methotrexate (usually in high dosage) along with some NSAIDs. Hepatotoxicity, fibrosis, and cirrhosis may occur with prolonged use. Lung disease, including acute or chronic interstitial pneumonitis may occur, and has been reported at low doses. Diarrhea and ulcerative stomatitis require therapy interruption. Methotrexate elimination is reduced in patients with impaired renal function, ascites, or pleural effusions; dose reduction is required and discontinuation may be necessary with these conditions. Increased risk of soft tissue necrosis and osteonecrosis with concomitant radiotherapy. Malignant lymphoma may occur .

Injection route(Powder for Solution;Solution)

Only use for life-threatening neoplastic disease or severe rheumatoid arthritis and psoriasis unresponsive to other therapies. Death, fetal death and/or congenital anomalies, lung disease, tumor lysis syndrome, fatal skin reactions, and Pneumocystis carinii pneumonia have been reported. Monitor for bone marrow, liver, lung, and kidney toxicities. Unexpectedly severe (sometimes fatal) bone marrow suppression, aplastic anemia, and gastrointestinal toxicity have been reported with concomitant administration of methotrexate (usually in high dosage) along with some nonsteroidal anti-inflammatory drugs (NSAIDs). Hepatotoxicity, fibrosis, and cirrhosis occur with prolonged use. Diarrhea and ulcerative stomatitis require interruption of therapy. Methotrexate elimination is reduced in patients with impaired renal function, ascites, or pleural effusions. Increased risk of soft tissue necrosis and osteonecrosis with concomitant radiotherapy. Malignant lymphoma may occur. Use extreme caution with high-dose regimen for osteosarcoma. Do not use formulations/diluents with preservatives for intrathecal or high-dose therapy .

Uses for RediTrex

Methotrexate injection is used alone or together with other medicines to treat several types of cancer, such as breast, head and neck, lung, blood, bone, lymph node, and uterus cancers.

Methotrexate is also used to treat severe rheumatoid arthritis in adults and polyarticular juvenile idiopathic arthritis in children who had other treatments that did not work well. It is also used to control symptoms of severe psoriasis in adults who have not been helped by other treatments.

Methotrexate belongs to the group of medicines known as antineoplastics (cancer medicines). It blocks an enzyme that is needed by cells to live. This interferes with the growth of cancer cells, which are eventually destroyed by the body. For patients with arthritis or psoriasis, methotrexate may work by improving the immune system.

This medicine is available only with your doctor's prescription.

Before using RediTrex

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of methotrexate injection for the treatment of cancer and juvenile idiopathic arthritis in children. However, safety and efficacy have not been established in children with psoriasis.

Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of Otrexup™ or Reditrex® for the treatment of juvenile idiopathic arthritis in children. However, safety and efficacy have not been established in children with cancer and psoriasis.

Geriatric

Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of methotrexate injection in the elderly. However, elderly patients are more likely to have bone marrow, liver, or kidney problems, which may require caution and an adjustment in the dose in patients receiving methotrexate injection.

Breast Feeding

Studies in women breastfeeding have demonstrated harmful infant effects. An alternative to this medication should be prescribed or you should stop breastfeeding while using this medicine.

Interactions with Medicines

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.

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. 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 is usually not recommended, but may be unavoidable in some cases. If used together, your doctor may change the dose or how often you use this medicine, or give you special instructions about the use of food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

Proper use of RediTrex

A nurse or other trained health professional will give you this medicine in a hospital or cancer treatment center. This medicine is given as a shot under your skin, into a muscle, into a vein, or into your spine (back or neck).

If you are using the Otrexup™ or Rasuvo® or Reditrex® injection at home:

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

Missed Dose

This medicine needs to be given on a fixed schedule. If you miss a dose or forget to use your medicine, call your doctor or pharmacist for instructions.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Put used syringe in a puncture-resistant disposable container.

Precautions while using RediTrex

It is very important that your doctor check your progress at regular visits to make sure this medicine is working properly and to check for unwanted effects. Blood tests and chest x-rays may be needed to check for unwanted effects.

Using this medicine while you are pregnant can harm your unborn baby. The medicine may also cause birth defects if it is used by the father when his sexual partner becomes pregnant. If you are a woman who can bear children, your doctor may give you a pregnancy test before you start using this medicine to make sure you are not pregnant. Female patients should use an effective form of birth control during treatment and for at least 6 months after the last dose. Male patients who have female partners should use an effective form of birth control during treatment and for at least 3 months after the last dose. Tell your doctor right away if pregnancy occurs while you are using this medicine.

Talk with your doctor before using this medicine if you plan to have children. Some men and women who use this medicine have become infertile (unable to have children).

Limit alcohol use with this medicine. Alcohol may increase the risk for liver problems.

This medicine may cause organ system toxicity. Call your doctor right away if you have the following symptoms: a fever, confusion, diarrhea, dry cough, irritability, neck stiffness, seizures, severe skin rash, sleepiness, trouble breathing, weakness, vomiting, or problems with coordination.

Check with your doctor right away if you have pain or tenderness in the upper stomach, pale stools, dark urine, loss of appetite, nausea, vomiting, or yellow eyes or skin. These could be symptoms of a serious liver problem.

This medicine may cause serious nerve problems. Check with your doctor right away if you have seizures, confusion, tingling or numbness in your hands, feet, or lips, trouble seeing, or headache.

Methotrexate can lower the number of white blood cells in your blood, which increases the chance of getting an infection. It can also lower the number of platelets, which are necessary for proper blood clotting. If this occurs, there are certain precautions you can take, especially when your blood count is low, to reduce the risk of infection or bleeding:

While you are being treated with methotrexate, and after you stop treatment with it, do not have any immunizations (vaccines) without your doctor's approval. Methotrexate may lower your body's resistance and the vaccine may not work as well or you might get the infection the vaccine is meant to prevent. In addition, you should not be around other persons living in your household who receive live virus vaccines because there is a chance they could pass the virus on to you. Some examples of live vaccines include measles, mumps, influenza (nasal flu vaccine), poliovirus (oral form), rotavirus, and rubella. Do not get close to them and do not stay in the same room with them for very long. If you have questions about this, talk to your doctor.

Check with your doctor right away if you have cough, fever, or trouble breathing. These could be symptoms of a serious lung or breathing problems (eg, acute or chronic interstitial pneumonitis).

Tell your doctor right away if you have a change in how much or how often you urinate, rapid weight gain, swelling in the legs, ankles, or feet, or trouble breathing. These could be symptoms of a serious kidney problem.

Serious skin reactions (eg, toxic epidermal necrolysis, Stevens-Johnson syndrome, exfoliative dermatitis, skin necrosis, or erythema multiforme) can occur with this medicine. Check with your doctor right away if you have blistering, peeling, or loosening of the skin, blue-green to black skin discoloration, cough, cracks in the skin, diarrhea, itching, joint or muscle pain, loss of heat from the body, red irritated eyes, red skin lesions, often with a purple center, sore throat, sores, ulcers, or white spots in the mouth or on the lips, fever or chills, or unusual tiredness or weakness while you are using this medicine.

This medicine may make your skin more sensitive to sunlight. Use a sunscreen when you are outdoors. Avoid sunlamps and tanning beds.

This medicine may make you dizzy or tired. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.

This medicine may increase your risk of having a lymphoma (cancer of the lymph system). Discuss these possible effects with your doctor.

This medicine may cause a serious reaction called tumor lysis syndrome. Tell your doctor right away if you have a change in urine amount, joint pain, stiffness, or swelling, lower back, side, or stomach pain, rapid weight gain, swelling of the feet or lower legs, or unusual tiredness or weakness.

Using this medicine with radiation therapy may increase risk of tissue or bone problems, such as tissue or bone not receiving enough blood. Tell your doctor if you are receiving other treatments, including radiation therapy, while using this medicine.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Side Effects of RediTrex

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

Less common

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:

More common

Less common

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.

Commonly used brand name(s)

In the U.S.

Available Dosage Forms:

Therapeutic Class: Antirheumatic

Pharmacologic Class: Antimetabolite

Frequently asked questions

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.