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PEMETREXED

Medical Diagnosis and Drugs, Medications
PEMETREXED
(pe-me-trex'ed)
Alimta
Classifications: antineoplastic agent; antimetabolite, antifolate;
Therapeutic: antineoplastic; antimetabolite; antifolate
Prototype: Methotrexate
Pregnancy Category: D

Availability

500 mg powder for injection

Action

Suppresses tumor growth by inhibiting both DNa synthesis and folate metabolism at multiple target enzymes.

Therapeutic Effect

Appears to arrest the cell cycle, thus inhibiting tumor growth.

Uses

Treatment of malignant pleural mesothelioma that is unresectable or in patients that are not surgery candidates in combination with cisplatin; treatment of locally advanced or metastatic non-small cell lung cancer (NSCLC).

Unlabeled Uses

Solid tumors, including bladder, breast, colorectal, gastric, head and neck, pancreatic, and renal cell cancers.

Contraindications

Mannitol hypersensitivity; creatinine clearance is <45 mL/min, renal failure, moderate or severe renal impairment; active infection; vaccines; children <18 y; pregnancy (category D); lactation.

Cautious Use

Anemia, thrombocytopenia, neutropenia, dental disease; older adults; hepatic disease, hypoalbuminemia, hypovolemia, dehydration, ascites, pleural effusion.

Route & Dosage

Malignant Mesothelioma, Non-Small Cell Lung Cancer
Adult: IV 500 mg/m2 on day 1 of each 21-d cycle

Renal Impairment
Not recommended if Clcr <45 mL/min.

Administration

Intravenous
  • Pre-/posttreatment with folic acid, vitamin B12, and dexamethasone are needed to reduce hematologic and gastrointestinal toxicity, and the possibility of severe cutaneous reactions from pemetrexed.

PREPARE: IV Infusion: Reconstitute each 500 mg vial with 20 mL of preservative-free NS. Do not use any other diluent. Swirl gently to dissolve. Each vial will contain 25 mg/mL. Withdraw the needed amount of reconstituted solution and add to 100 mL of preservative-free NS. Discard any unused portion.  

ADMINISTER: IV Infusion: Do NOT give a bolus dose. Infuse over 10 min.  

INCOMPATIBILITIES Solution/additive: Solutions containing calcium, lactated Ringer's. Y-site: Amphotericin B, calcium, cefazolin, cefotaxime, cefotetan, cefoxitin, ceftazidime, chlorpromazine, ciprofloxacin, dobutamine, doxorubicin, doxycycline, droperidol, gemcitabine, gentamicin, irinotecan, metronidazole, minocycline, mitoxantrone, nalbuphine, ondansetron, prochlorperazine, tobramycin, topotecan.

  • Store unopened single-use vials at room temperature between 15°–30° C (59°–86° F). The reconstituted drug is stable for up to 24 h at 2°–8° C (36°–46° F) or at 25° C (77° F).

Adverse Effects (≥1%)

Body as a Whole: Fatigue, fever, hypersensitivity reaction, edema, myalgia, arthralgia. CNS: Neuropathy, mood alteration, depression. CV: Chest pain, thromboembolism. GI: Nausea, vomiting, constipation, anorexia, stomatitis, diarrhea, dehydration, dysphagia, esophagitis, odynophagia, increased LFTs. Hematologic: Neutropenia, leukopenia, anemia, thrombocytopenia. Respiratory: Dyspnea. Skin: Rash, desquamation, alopecia. Urogenital: Increases serum creatinine, renal failure.

Interactions

Drug: Increased risk of renal toxicity with other nephrotoxic drugs (acyclovir, adefovir, amphotericin B, aminoglycosides, carboplatin, cidofovir, cisplatin, cyclosporine, foscarnet, ganciclovir, sirolimus, tacrolimus, vancomycin); nsaids may increase risk of renal toxicity in patients with preexisting renal insufficiency; may cause additive risk of bleeding with anticoagulants, platelet inhibitors, aspirin, thrombolytic agents.

Pharmacokinetics

Metabolism: Not extensively. Elimination: Primarily in urine. Half-Life: 3.5 h.

Nursing Implications

Assessment & Drug Effects

  • Withhold drug and notify physician if the absolute neutrophil count (ANC) is <1500 cells/mm3 or the platelet count is less than at least 100,000 cells/mm3, or if the Clcr is <45 mL/min.
  • Lab tests: Baseline and periodic CBC with differential; monitor for nadir and recovery before each dose (on day 8 and 15, respectively, of each cycle); periodic LFTs, serum creatinine and BUN.
  • Notify physician for S&S of neuropathy (paresthesia) or thromboembolism.

Patient & Family Education

  • Report promptly any of the following to physician: symptoms of anemia (e.g., chest pain, unusual weakness or tiredness, fainting spells, lightheadedness, shortness of breath); symptoms of poor blood clotting (e.g., bruising; red spots on skin; black, tarry stools; blood in urine); symptoms of infection (e.g., fever or chills, cough, sore throat, pain or difficulty passing urine); symptoms of liver problems (e.g., yellowing of skin).
  • Do not take nonsteroidal antiinflammatory drugs (NSAIDs) without first consulting the physician.

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug

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