Skip to content
ppharmaranks
Menu

otrexup

Otrexup (Methotrexate) is a folate analog metabolic inhibitor used to treat Juvenile Arthritis, Rheumatoid Arthritis, Breast Neoplasms, Choriocarcinoma.

Methotrexate · by Assertio Speclty

⚠ FDA reports a current shortage of the injection form — availability differs between suppliers — see drug shortages →
Not yet rated· sourced from the FDA label
Rated against independent regulatory sources·Last updated June 7, 2026·How we rate
Verified againstopenFDANIH DailyMedRxClass

Every strength approved under this FDA application (2)

  • Otrexup (this page)Methotrexate 10MG/0.4ML (10MG/0.4ML) · Methotrexate 12.5MG/0.4ML (12.5MG/0.4ML) · Methotrexate 15MG/0.4ML (15MG/0.4ML) · Methotrexate 17.5MG/0.4ML (17.5MG/0.4ML) · Methotrexate 20MG/0.4ML (20MG/0.4ML) · Methotrexate 22.5MG/0.4ML (22.5MG/0.4ML) · Methotrexate 25MG/0.4ML (25MG/0.4ML) · Methotrexate 7.5MG/0.4ML (7.5MG/0.4ML)
  • Otrexup PfsMethotrexate 10MG/0.4ML (10MG/0.4ML) · Methotrexate 15MG/0.6ML (15MG/0.6ML) · Methotrexate 17.5MG/0.7ML (17.5MG/0.7ML) · Methotrexate 20MG/0.8ML (20MG/0.8ML) · Methotrexate 22.5MG/0.9ML (22.5MG/0.9ML) · Methotrexate 25MG/ML (25MG/ML)

Key facts

Active ingredient
Methotrexate
Form
Injectable
Strength
Methotrexate 10MG/0.4ML (10MG/0.4ML) · Methotrexate 12.5MG/0.4ML (12.5MG/0.4ML) · Methotrexate 15MG/0.4ML (15MG/0.4ML) · Methotrexate 17.5MG/0.4ML (17.5MG/0.4ML) · Methotrexate 20MG/0.4ML (20MG/0.4ML) · Methotrexate 22.5MG/0.4ML (22.5MG/0.4ML) · Methotrexate 25MG/0.4ML (25MG/0.4ML) · Methotrexate 7.5MG/0.4ML (7.5MG/0.4ML)
Type
Prescription (Rx)
Brand or generic
Brand-name
Manufacturer
Assertio Speclty
Half-life
about 3 to 10 hours (how long it stays in your system)
What the pharmacy pays
~$4.92 for 30 — not your price
FDA application
NDA204824
Availability
Discontinued (per FDA)

What is Otrexup?

From the FDA label:Otrexup contains methotrexate, a folate analog metabolic inhibitor. Chemically, methotrexate is [N-[4-[[(2,4-diamino-6-pteridinyl)methyl]methylamino]benzoyl]-Lglutamic acid. The structural formula is: C 20 H 22 N 8 O 5 M.W.= 454.45 Otrexup contains methotrexate in a sterile, preservative-free, unbuffered solution with a 27 gauge ½ inch needle for a single subcutaneous injection. Otrexup solution is yellow in color. Inactive ingredients include sodium chloride and water for injection, USP. The amounts of sodium chloride vary with the amount of methotrexate. Amount of methotrexate (mg) per 0.4 mL 10 12.5 15 17.5 20 22.5 25 Amount of sodium chloride (mg) per 0.4 mL 1.96 2.04 1.60 1.48 1.28 0.92 0.56 Hydrochloric acid and additional sodium hydroxide may have been added, if necessary, to adjust the pH to 8.0. Structure

How to use

Otrexup is for once weekly subcutaneous use only. Administer Otrexup in the abdomen or thigh. ( 2.1 ). Use another formulation of methotrexate for patients requiring oral, intramuscular, intravenous, intra-arterial, or intrathecal dosing, doses less than 10 mg per week, doses above 25 mg per week, high-dose regimens, or dose adjustments of less than 5 mg increments ( 2.1 ). Starting doses of methotrexate: RA: 7.5 mg once weekly ( 2.2 ). pJIA: 10 mg/m 2 once weekly ( 2.2 ). Psoriasis: 10 to 25 mg once weekly of an oral, intramuscular, subcutaneous, or intravenous formulation ( 2.3 ). Adjust dose gradually to achieve an optimal response ( 2.2 , 2.3 ). 2.1 Important Dosing Information Otrexup is a single-dose auto-injector for once-weekly subcutaneous use only [see Warnings and Precautions ( 5.5 )] . Administer Otrexup in the abdomen or the thigh. Otrexup is available in the following dosage strengths: 10, 12.5, 15, 17.5, 20, 22.5 and 25 mg. Use another formulation of methotrexate for alternative dosing in patients who require oral, intramuscular, intravenous, intra-arterial, or intrathecal dosing, doses less than 10 mg per week, doses more than 25 mg per week, high-dose regimens, or dose adjustments between the available doses. 2.2 Rheumatoid Arthritis including Polyarticular Juvenile Idiopathic Arthritis Recommended starting dose of methotrexate: Adult RA: 7.5 mg once weekly.…

Side effects

The following adverse reactions are discussed in more detail in other sections of the labeling. Organ System Toxicity [see Warnings and Precautions ( 5.1 )] Embryo-Fetal Toxicity [see Warnings and Precautions ( 5.2 )] Effects on Reproduction [see Warnings and Precautions ( 5.3 )] Malignant Lymphomas [see Warnings and Precautions ( 5.8 )] The most frequently reported adverse reactions include ulcerative stomatitis, leukopenia, nausea, and abdominal distress. Other frequently reported adverse reactions are malaise, undue fatigue, chills and fever, dizziness and decreased resistance to infection. Common adverse reactions are: nausea, abdominal pain, dyspepsia, stomatitis/mouth sores, rash, nasopharyngitis, diarrhea, liver function test abnormalities, vomiting, headache, bronchitis, thrombocytopenia, alopecia, leucopenia, pancytopenia, dizziness, photosensitivity, and “burning of skin lesions” ( 6 ). To report SUSPECTED ADVERSE REACTIONS, contact Antares at 1-855-Otrexup (1-855-687-3987) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience This section provides a summary of adverse reactions reported in subjects in clinical studies conducted with Otrexup as well as with methotrexate injection and oral methotrexate. Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug…

FDA Boxed Warning (the FDA’s most serious warning)

Boxed (black-box) warning — from the FDA label

Otrexup should be used only by physicians whose knowledge and experience include the use of antimetabolite therapy. Because of the possibility of serious toxic reactions (which can be fatal), Otrexup should be used only in patients with psoriasis or rheumatoid arthritis with severe, recalcitrant, disabling disease which is not adequately responsive to other forms of therapy. Deaths have been reported with the use of methotrexate in the treatment of malignancy, psoriasis, and rheumatoid arthritis. Patients should be closely monitored for bone marrow, liver, lung, skin, and kidney toxicities. Patients should be informed by their physician of the risks involved and be under a physician’s care throughout therapy [see Warnings and Precautions ( 5.1 )]. 1. Methotrexate can cause embryo-fetal toxicity, including fetal death. Use is contraindicated during pregnancy. Verify the pregnancy status of females of reproductive potential prior to initiating therapy. Advise females and males of reproductive potential to use effective contraception during and after treatment with Otrexup [see Contraindications ( 4 ), Warnings and Precautions ( 5.2 ), and Use in Specific Populations ( 8.1 , 8.3 )]. 2. Methotrexate elimination is reduced in patients with impaired renal functions, ascites, or pleural effusions. Such patients require especially careful monitoring for toxicity, and require dose reduction or, in some cases, discontinuation of Otrexup administration [see Warnings and Precautions ( 5.6 )] . 3. 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) [see Warnings and Precautions ( 5.1 ) and Drug Interactions ( 7.1 )]. 4. Methotrexate causes hepatotoxicity, fibrosis and cirrhosis, but generally only after prolonged use. Acutely, liver enzyme elevations are frequently seen. These are usually transient and asymptomatic, and also do not appear predictive of subsequent hepatic disease. Liver biopsy after sustained use often shows histologic changes, and fibrosis and cirrhosis have been reported; these latter lesions may not be preceded by symptoms or abnormal liver function tests in the psoriasis population. For this reason, periodic liver biopsies are usually recommended for psoriatic patients who are under long-term treatment. Persistent abnormalities in liver function tests may precede appearance of fibrosis or cirrhosis in the rheumatoid arthritis population [see Warnings and Precautions ( 5.1 )]. 5. Methotrexate-induced lung disease, including acute or chronic interstitial pneumonitis, is a potentially dangerous lesion, which may occur acutely at any time during therapy and has been reported at low doses. It is not always fully reversible and fatalities have been reported. Pulmonary symptoms (especially a dry, nonproductive cough) may require interruption of treatment and careful investigation [see Warnings and Precautions ( 5.1 )]. 6. Diarrhea and ulcerative stomatitis require interruption of therapy: otherwise, hemorrhagic enteritis and death from intestinal perforation may occur [see Warnings and Precautions ( 5.1 )]. 7. Malignant lymphomas, which may regress following withdrawal of methotrexate, may occur in patients receiving low-dose methotrexate and, thus, may not require cytotoxic treatment. Discontinue Otrexup first and, if the lymphoma does not regress, appropriate treatment should be instituted [see Warnings and Precautions ( 5.8 )] . 8. Like other cytotoxic drugs, methotrexate may induce “tumor lysis syndrome” in patients with rapidly growing tumors [see Warnings and Precautions ( 5.9 )] . 9. Severe, occasionally fatal, skin reactions have been reported following single or multiple doses of methotrexate. Reactions have occurred within days of oral, intramuscular, intravenous, or intrathecal methotrexate administration. Recovery has been reported with discontinuation of therapy [see Warnings and Precautions ( 5.1 )] . 10. Potentially fatal opportunistic infections, especially Pneumocystis jiroveci pneumonia, may occur with methotrexate therapy [see Warnings and Precautions ( 5.1 )] . 11. Methotrexate given concomitantly with radiotherapy may increase the risk of soft tissue necrosis and osteonecrosis [see Warnings and Precautions ( 5.10 )] . WARNING: SEVERE TOXIC REACTIONS, INCLUDING EMBRYO-FETAL TOXICITY AND DEATH See full prescribing information for complete boxed warning. • Serious toxic reactions and death have been reported with the use of methotrexate. Patients should be closely monitored for bone marrow, liver, lung, skin, and kidney toxicities ( 5.1 ). • Methotrexate can cause embryo-fetal toxicity, including fetal death. Use is contraindicated during pregnancy ( 4 ). Advise females and males of reproductive potential to use effective contraception during and after treatment with methotrexate ( 5.2 , 8.1 , 8.3 ). • 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) ( 5.1 ). • Hepatotoxicity, fibrosis, and cirrhosis may occur after prolonged use ( 5.1 ). • Methotrexate may cause interstitial pneumonitis at any time during therapy and has been reported at low doses. Pulmonary symptoms (especially a dry, nonproductive cough) may require interruption of treatment and careful investigation ( 5.1 ). • Diarrhea, ulcerative stomatitis, hemorrhagic enteritis, and death from intestinal perforation may occur ( 5.1 ). • Severe, occasionally fatal, skin reactions have been reported ( 5.1 ). • Potentially fatal opportunistic infections may occur ( 5.1 ).

Warnings

Important safety information

Organ system toxicity: Potential for serious toxicity. Only for use by physicians experienced in antimetabolite therapy ( 5.1 ). Effects on reproduction: May cause impairment of fertility, oligospermia and menstrual dysfunction ( 5.3 , 8.3 ). Laboratory tests: Monitor complete blood counts, renal function and liver function tests ( 5.4 ). Risks from improper dosing: Mistaken daily use has led to fatal toxicity ( 5.5 ). Patients with impaired renal function, ascites, or pleural effusions: Elimination is reduced ( 5.6 ). Dizziness and fatigue: May impair ability to drive or operate machinery ( 5.7 ). 5.1 Organ System Toxicity Otrexup should be used only by physicians whose knowledge and experience include the use of antimetabolite therapy. Because of the possibility of serious toxic reactions (which can be fatal), Otrexup should be used only in patients with psoriasis or rheumatoid arthritis with severe, recalcitrant, disabling disease which is not adequately responsive to other forms of therapy. Deaths have been reported with the use of methotrexate in the treatment of malignancy, psoriasis, and rheumatoid arthritis. Patients should be closely monitored for bone marrow, liver, lung and kidney toxicities. Otrexup has the potential for serious toxicity. Toxic effects may be related in frequency and severity to dose or frequency of administration but have been seen at all doses. Because they can occur at any time during therapy, it is necessary to follow patients on Otrexup closely. Most adverse reactions are reversible if detected early. When such reactions do occur, the drug should be reduced in dosage or discontinued and appropriate corrective measures should be taken. If necessary, this could include the use of leucovorin calcium and/or acute, intermittent hemodialysis with a high-flux dialyzer [see Overdosage ( 10 )] . If Otrexup therapy is reinstituted, it should be carried out with caution, with adequate consideration of further need for the drug and increased alertness as to possible recurrence of toxicity. The clinical pharmacology of methotrexate has not been well studied in older individuals. Due to diminished hepatic and renal function as well as decreased folate stores in this population, relatively low doses should be considered, and these patients should be closely monitored for early signs of toxicity [see Use in Specific Populations ( 8.5 )]. Gastrointestinal: Diarrhea and ulcerative stomatitis require interruption of therapy: otherwise, hemorrhagic enteritis and death from intestinal perforation may occur. If vomiting, diarrhea, or stomatitis occur, which may result in dehydration, Otrexup should be discontinued until recovery occurs. Otrexup should be used with extreme caution in the presence of peptic ulcer disease or ulcerative colitis. Unexpectedly severe (sometimes fatal) gastrointestinal toxicity has been reported with concomitant administration of methotrexate (usually in high dosage) along with some nonsteroidal anti-inflammatory drugs (NSAIDs) [see Drug Interactions ( 7.1 )]. Hematologic: Otrexup can suppress hematopoiesis and cause anemia, aplastic anemia, pancytopenia, leukopenia, neutropenia, and/or thrombocytopenia. In patients with preexisting hematopoietic impairment, Otrexup should be used with caution, if at all. In controlled clinical trials conducted with another formulation of methotrexate in rheumatoid arthritis (n=128), leukopenia (WBC <3000/mm 3 ) was seen in 2 patients, thrombocytopenia (platelets <100,000/mm 3 ) in 6 patients, and pancytopenia in 2 patients. Otrexup should be stopped immediately if there is a significant drop in blood counts. Patients with profound granulocytopenia and fever should be evaluated immediately and usually require parenteral broad-spectrum antibiotic therapy. Unexpectedly severe (sometimes fatal) bone marrow suppression and aplastic anemia have been reported with concomitant administration of methotrexate (usually in high dosage) along with some nonsteroidal anti-inflammatory drugs (NSAIDs ) [see Drug Interactions ( 7.1 )]. Hepatic: Otrexup has the potential for acute (elevated transaminases) and chronic (fibrosis and cirrhosis) hepatotoxicity. Chronic toxicity is potentially fatal; it generally has occurred after prolonged use (generally two years or more) and after a total dose of at least 1.5 grams. In studies in psoriatic patients, hepatotoxicity appeared to be a function of total cumulative dose and appeared to be enhanced by alcoholism, obesity, diabetes and advanced age. An accurate incidence rate has not been determined; the rate of progression and reversibility of lesions is not known. Special caution is indicated in the presence of preexisting liver damage or impaired hepatic function. In psoriasis, liver function tests, including serum albumin, should be performed periodically prior to dosing but are often normal in the face of developing fibrosis or cirrhosis. These lesions may be detectable only by biopsy. The usual recommendation is to obtain a liver biopsy at 1) pretherapy or shortly after initiation of therapy (2 to 4 months), 2) a total cumulative dose of 1.5 grams, and 3) after each additional 1.0 to 1.5 grams. Moderate fibrosis or any cirrhosis normally leads to discontinuation of the drug; mild fibrosis normally suggests a repeat biopsy in 6 months. Milder histologic findings such as fatty change and low grade portal inflammation, are relatively common pretherapy. Although these mild changes are usually not a reason to avoid or discontinue Otrexup therapy, the drug should be used with caution. In rheumatoid arthritis, age at first use of methotrexate and duration of therapy have been reported as risk factors for hepatotoxicity; other risk factors, similar to those observed in psoriasis, may be present in rheumatoid arthritis but have not been confirmed to date. Persistent abnormalities in liver function tests may precede appearance of fibrosis or cirrhosis in this population. There is a combined reported experience in 217 rheumatoid arthritis patients with liver biopsies both before and during treatment (after a cumulative dose of at least 1.5 g) and in 714 patients with a biopsy only during treatment. There are 64 (7%) cases of fibrosis and 1 (0.1%) case of cirrhosis. Of the 64 cases of fibrosis, 60 were deemed mild. The reticulin stain is more sensitive for early fibrosis and its use may increase these figures. It is unknown whether even longer use will increase these risks. Liver function tests should be performed at baseline at 4 to 8 week intervals in patients receiving Otrexup for rheumatoid arthritis. Pretreatment liver biopsy should be performed for patients with a history of excessive alcohol consumption, persistently abnormal baseline liver function test values or chronic hepatitis B or C infection. During therapy, liver biopsy should be performed if there are persistent liver function test abnormalities or there is a decrease in serum albumin below the normal range (in the setting of well controlled rheumatoid arthritis). If the results of a liver biopsy show mild changes (Roenigk, grades I, II, IIIa), Otrexup may be continued and the patient monitored as per recommendations listed above. Otrexup should be discontinued in any patient who displays persistently abnormal liver function tests and refuses liver biopsy or in any patient whose liver biopsy shows moderate to severe changes (Roenigk grade IIIb or IV). Infection or Immunologic States: Otrexup should be used with extreme caution in the presence of active infection, and is contraindicated in patients with overt or laboratory evidence of immunodeficiency syndromes. Immunization may be ineffective when given during Otrexup therapy. Immunization with live virus vaccines is generally not recommended. There have been reports of disseminated vaccinia infections after smallpox immunizations in patients receiving methotrexate therapy. Hypogammaglobulinemia has been reported rarely. Potentially fatal…

Who should not take Otrexup

Otrexup is contraindicated in the following: • Pregnancy Otrexup can cause embryo-fetal toxicity and fetal death when administered during pregnancy [see Warnings and Precautions ( 5.2 ) and Use in Specific Populations ( 8.1 )]. • Alcoholism or Liver Disease Patients with alcoholism, alcoholic liver disease or other chronic liver disease [see Warnings and Precautions ( 5.1 ) ]. • Immunodeficiency Syndromes Patients who have overt or laboratory evidence of immunodeficiency syndromes [ see Warnings and Precautions ( 5.1 ) ]. • Preexisting Blood Dyscrasias Patients who have preexisting blood dyscrasias, such as bone marrow hypoplasia, leukopenia, thrombocytopenia, or significant anemia [see Warnings and Precautions ( 5.1 )]. • Hypersensitivity Patients with a known hypersensitivity to methotrexate. Severe hypersensitivity reactions have been observed with methotrexate use [see Warnings and Precautions ( 5.1 ) and Adverse Reactions ( 6.1 and 6.2 )]. Pregnancy ( 4 ) Alcoholism or liver disease ( 4 ) Immunodeficiency syndromes ( 4 ) Preexisting blood dyscrasias ( 4 ) Hypersensitivity to methotrexate ( 4 )

Overdose — what happens if you take too much

Leucovorin is indicated to diminish the toxicity and counteract the effect of inadvertently administered overdosages of methotrexate. Leucovorin administration should begin as promptly as possible. As the time interval between methotrexate administration and leucovorin initiation increases, the effectiveness of leucovorin in counteracting toxicity decreases. Monitoring of the serum methotrexate concentration is essential in determining the optimal dose and duration of treatment with leucovorin. In cases of massive overdosage, hydration and urinary alkalinization may be necessary to prevent the precipitation of methotrexate and/or its metabolites in the renal tubules. Generally speaking, neither hemodialysis nor peritoneal dialysis has been shown to improve methotrexate elimination. However, effective clearance of methotrexate has been reported with acute, intermittent hemodialysis using a high-flux dialyzer (Wall, SM et al: Am J Kidney Dis 28 (6): 846-854, 1996). Accidental intrathecal overdosage may require intensive systemic support, high-dose systemic leucovorin, alkaline diuresis and rapid CSF drainage and ventriculolumbar perfusion. In postmarketing experience, overdose with methotrexate has generally occurred with oral and intrathecal administration, although intravenous and intramuscular overdose have also been reported. Reports of oral overdose often indicate…

U.S. Poison Control: call or text 1-800-222-1222 (free, 24/7). In an emergency call 911. From the FDA label; not medical advice.

Interactions

Aspirin, NSAIDs, and steroids: concomitant use may elevate and prolong serum methotrexate levels and cause increased toxicity ( 7.1 ). Proton pump inhibitors : concomitant use may elevate and prolong serum methotrexate levels and cause increased toxicity ( 7.2 ). 7.1 Aspirin, Nonsteroidal Anti-Inflammatory Drugs, and Steroids Nonsteroidal anti-inflammatory drugs (NSAIDs) should not be administered prior to or concomitantly with the high doses of methotrexate, such as used in the treatment of osteosarcoma. Concomitant administration of some NSAIDs with high dose methotrexate therapy has been reported to elevate and prolong serum methotrexate levels, resulting in deaths from severe hematologic and gastrointestinal toxicity [see Warnings and Precautions ( 5.1 )]. Caution should be used when NSAIDs and salicylates are administered concomitantly with lower doses of methotrexate, including Otrexup. These drugs have been reported to reduce the tubular secretion of methotrexate in an animal model and may enhance its toxicity. Despite the potential interactions, studies of methotrexate in patients with rheumatoid arthritis have usually included concurrent use of constant dosage regimens of NSAIDs, without apparent problems. It should be appreciated, however, that the doses used in rheumatoid arthritis (7.5 to 15 mg/week) are somewhat lower than those used in psoriasis and that larger doses could lead to unexpected toxicity. Aspirin, NSAIDs, and/or low dose steroids may be continued, although the possibility of increased toxicity with concomitant use of NSAIDs including salicylates has not been fully explored. Steroids may be reduced gradually in patients who respond to methotrexate. 7.2 Proton Pump Inhibitors (PPIs) Use caution if high-dose methotrexate is administered to patients receiving proton pump inhibitor (PPI) therapy. Case reports and published population pharmacokinetic studies suggest that concomitant use of some PPIs, such as omeprazole, esomeprazole, and pantoprazole, with methotrexate (primarily at high dose), may elevate and prolong serum levels of methotrexate and/or its metabolite hydroxymethotrexate, possibly leading to methotrexate toxicities. In two of these cases, delayed methotrexate elimination was observed when high-dose methotrexate was co-administered with PPIs, but was not observed when methotrexate was co-administered with ranitidine. However, no formal drug interaction studies of methotrexate with ranitidine have been conducted. 7.3 Oral Antibiotics Oral antibiotics such as tetracycline, chloramphenicol, and nonabsorbable broad spectrum antibiotics, may decrease intestinal absorption of methotrexate or interfere with the enterohepatic circulation by inhibiting bowel flora and suppressing metabolism of the drug by bacteria. Penicillins may reduce the renal clearance of methotrexate; increased serum concentrations of methotrexate with concomitant hematologic and gastrointestinal toxicity have been observed with high and low dose methotrexate. Use of Otrexup with penicillins should be carefully monitored. Trimethoprim/sulfamethoxazole has been reported rarely to increase bone marrow suppression in patients receiving methotrexate, probably by decreased tubular secretion and/or an additive antifolate effect. 7.4 Hepatotoxins The potential for increased hepatotoxicity when methotrexate is administered with other hepatotoxic agents has not been evaluated. However, hepatotoxicity has been reported in such cases. Therefore, patients receiving concomitant therapy with Otrexup and other potential hepatotoxins (e.g., azathioprine, retinoids, and sulfasalazine) should be closely monitored for possible increased risk of hepatotoxicity. 7.5 Theophylline Methotrexate may decrease the clearance of theophylline; theophylline levels should be monitored when used concurrently with Otrexup. 7.6 Folic Acid and Antifolates Vitamin preparations containing folic acid or its derivatives may decrease responses to systemically administered methotrexate. Preliminary animal and human studies have shown that small quantities of intravenously administered leucovorin enter the CSF primarily as 5-methyltetrahydrofolate and, in humans, remain 1 to 3 orders of magnitude lower than the usual methotrexate concentrations following intrathecal administration. However, high doses of leucovorin may reduce the efficacy of intrathecally administered methotrexate. Folate deficiency states may increase methotrexate toxicity. Trimethoprim/sulfamethoxazole has been reported rarely to increase bone marrow suppression in patients receiving methotrexate, probably by decreased tubular secretion and/or an additive antifolate effect. 7.7 Mercaptopurine Methotrexate increases the plasma levels of mercaptopurine. The combination of Otrexup and mercaptopurine may therefore require dose adjustment. 7.8 Nitrous Oxide The use of nitrous oxide anesthesia potentiates the effect of methotrexate on folate dependent metabolic pathways, resulting in the potential for increased toxicity. Avoid concomitant nitrous oxide anesthesia in patients receiving methotrexate. 7.9 Other Drugs Methotrexate is partially bound to serum albumin, and toxicity may be increased because of displacement by certain drugs, such as salicylates, phenylbutazone, phenytoin, and sulfonamides. Renal tubular transport is also diminished by probenecid; use of Otrexup with this drug should be carefully monitored. Combined use of methotrexate with gold, penicillamine, hydroxychloroquine, sulfasalazine, or cytotoxic agents, has not been studied and may increase the incidence of adverse effects.

How long does Methotrexate stay in your body?

The elimination half-life of methotrexate is about 3 to 10 hours — the time it takes the body to clear about half of it. As a rule of thumb, a medicine is mostly gone after roughly 4 to 5 half-lives, though this varies from person to person with age and kidney or liver function. The 3-to-10-hour figure is for the low weekly doses used in rheumatoid arthritis, psoriasis, and low-dose cancer therapy (under 30 mg/m2). After high-dose intravenous methotrexate the terminal half-life is longer, 8 to 15 hours. Methotrexate leaves the bloodstream faster than it leaves the body's tissues: inside cells it is converted to methotrexate polyglutamates, active metabolites that the FDA label says "may remain in tissues for extended periods," with retention varying by tissue and tumor — the label gives no half-life number for them. A second active metabolite, 7-hydroxymethotrexate, is also formed in smaller amounts; the label states no half-life for it either. The drug is cleared mainly by the kidneys, and the label states that the elimination half-life increases with the severity of kidney impairment, with wide variation between individuals — relevant to older adults, whose kidney function declines with age. The effect of liver impairment on methotrexate pharmacokinetics is unknown per the label. There is no extended-release form of methotrexate; oral tablets, oral solution, and subcutaneous auto-injectors are all immediate-release.

This is general information, not medical advice. It doesn’t tell you when a drug test would read negative (tests detect substances for different, often longer, windows) or when it’s safe to take another dose — ask your pharmacist or prescriber. Source: Methotrexate Injection — FDA Prescribing Information, Section 12.3 Pharmacokinetics (DailyMed).

Drug class

How this class works, per Methotrexate - StatPearls - NCBI Bookshelf.

May treat (source: NIH RxClass)

See how Otrexup ranks — best-rated folate analog metabolic inhibitor for:

Dosage forms

Injectable

The forms currently marketed in the U.S., per the FDA National Drug Code Directory.

Ways to save

Ask for the generic

Same active ingredient, far cheaper. Is there a generic? →

Request a 90-day supply

Bulk fills usually lower the per-dose price vs monthly refills.

Use copay cards

Manufacturer copay cards & patient-assistance programs — especially for brand drugs.

Compare alternatives

A same-class option may cost less. See alternatives →

Frequently asked questions

What does Otrexup treat?
Otrexup (Methotrexate) may be used to treat juvenile arthritis, rheumatoid arthritis, breast neoplasms, choriocarcinoma, crohn disease, esophageal neoplasms, based on NIH RxClass drug-classification data (conditions a drug may treat — not a verbatim copy of the FDA-approved label). This is general reference, not medical advice.
How does Otrexup work?
Otrexup is a folate analog metabolic inhibitor. Folate analog metabolic inhibitors like methotrexate block the enzyme that converts folate into its usable form, starving fast-dividing cells of the building blocks for DNA. At low doses they also calm an overactive immune system and reduce inflammation.
How much does Otrexup cost?
Nobody can tell you what you will pay — your price is set by your insurer's formulary, your deductible and the pharmacy's markup, and none of those are published. What IS published is what the pharmacy paid to acquire it: about $4.92 for 30, per the CMS NADAC survey. Treat that as the floor, not the quote — ask the pharmacist for the cash price as well as your copay, because for cheap generics the cash price often wins.
Is there a coupon or discount for Otrexup?
pharmaranks is an independent ratings site, not a pharmacy — we don't issue coupons or sell Otrexup. To pay less, ask your prescriber or pharmacist whether a generic equivalent exists, check the manufacturer's copay/savings card and patient-assistance program, and compare a pharmacy discount card against your insurance copay. Prices vary by pharmacy, insurance, and location, so always confirm at the counter. This is general reference, not medical or financial advice.
Who makes Otrexup?
Otrexup is marketed by Assertio Speclty. You can see Assertio Speclty's full profile, rating, and other products on pharmaranks.
Is Otrexup a brand-name or generic drug?
Otrexup is a brand-name product with the active ingredient Methotrexate.
Is Otrexup available over the counter?
No. Otrexup is a prescription (Rx) medication in the US — you need a prescription from a licensed clinician (in person or via telehealth); it isn't sold over the counter. For some conditions there are OTC alternatives — ask your pharmacist.
What forms does Otrexup come in?
Otrexup is currently marketed as injectable, per the FDA's National Drug Code Directory.
What class of drug is Otrexup?
Otrexup is classified as folate analog metabolic inhibitor, per the FDA's Established Pharmacologic Class.
Is Otrexup FDA-registered?
Otrexup is on record with the U.S. FDA under application number NDA204824. You can verify this on its official FDA label.
Is Otrexup safe?
There's no single safe-or-not verdict, and we don't yet have a composite recall-safety score for Otrexup. Review its FDA-label side effects and warnings below, and always consult a licensed professional.
What are the side effects of Otrexup?
Otrexup's side effects are taken directly from its FDA label. From the label: The following adverse reactions are discussed in more detail in other sections of the labeling. Organ System Toxicity [see Warnings and Precautions ( 5.1 )] Embryo-Fetal Toxicity [see Warnings and Precautions ( 5.2 )] Effects on Reproduction [see Warnings and Precautions ( 5.3 )] Malignant Lymphomas… Both common and serious reactions are documented in full on this page. This is general reference from the FDA, not medical advice — always consult a professional.

Clinical content sourced from the FDA label via openFDA (U.S. FDA). View the FDA label on DailyMed → Provided for general reference only — not medical advice. Always consult a licensed professional and the current prescribing information.

Reviews

No reviews yet. Be the first to write one.

Write a review

Reviews are user opinions, not medical advice. Consult a licensed professional.

People also viewed

Compare Otrexup head-to-head

More folate analog metabolic inhibitor drugs

Guides for this medication

Identify a pill by its imprint →Check a drug interaction →Drug recalls →

Browse medications A–Z

Research products from A to Z, compare independent ratings, and find alternatives.