Methotrexate: Difference between revisions
ClaireLewis (talk | contribs) (Created page with "==Administration== *Type: Immunosuppressant/antineoplastic *Dosage Forms: *Routes of Administration: IV/IM, oral *Common Trade Names: ==Adult Dosing== *Ectopic pregnancy: 5...") |
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==Adult Dosing== | ==Adult Dosing== | ||
*Ectopic pregnancy: | *Ectopic pregnancy: | ||
Single-dose regimen: Methotrexate 50 mg/m2 on day 1; Measure serum hCG levels on days 4 and 7; if needed, repeat dose on day 7 (Barnhart 2009) | |||
Two-dose regimen: Methotrexate 50 mg/m2 on day 1; Measure serum hCG levels on day 4 and administer a second dose of methotrexate 50 mg/m2; Measure serum hCG levels on day 7 and if needed, administer a third dose of 50 mg/m2 (Barnhart 2009) | |||
*Doses for treatment of malignancy or autoimmune diseases vary widely | *Doses for treatment of malignancy or autoimmune diseases vary widely | ||
==Pediatric Dosing== | ==Pediatric Dosing== | ||
Revision as of 17:53, 3 October 2016
Administration
- Type: Immunosuppressant/antineoplastic
- Dosage Forms:
- Routes of Administration: IV/IM, oral
- Common Trade Names:
Adult Dosing
- Ectopic pregnancy:
Single-dose regimen: Methotrexate 50 mg/m2 on day 1; Measure serum hCG levels on days 4 and 7; if needed, repeat dose on day 7 (Barnhart 2009) Two-dose regimen: Methotrexate 50 mg/m2 on day 1; Measure serum hCG levels on day 4 and administer a second dose of methotrexate 50 mg/m2; Measure serum hCG levels on day 7 and if needed, administer a third dose of 50 mg/m2 (Barnhart 2009)
- Doses for treatment of malignancy or autoimmune diseases vary widely
Pediatric Dosing
Special Populations
- Pregnancy Rating: X
- Lactation risk: Infant risk has been determined (risk of serious adverse effects for infant)
Renal Dosing
- Adult:
- Pediatric:
Hepatic Dosing
- Adult:
- Pediatric:
Contraindications
- Allergy to class/drug
- Breastfeeding, pregnant, or possibility of impregnating someone
- Blood dyscrasias
- Chronic liver disease
Adverse Reactions
Serious
- Hepatotoxicity
- Nephrotoxicity
- Myelosuppression, aplastic anemia, pancytopenia
- Infectious disease
- Tumor lysis syndrome
- GI bleed
- Neurotoxicity, seizure
- Pericardial effusion
- TEN
Common
- Nausea/vomiting, diarrhea
- Stomatitis
- Leukopenia, thrombocytopenia
- Alopecia, photosensitivity, rash
- Dizziness
Pharmacology
- Half-life: 8-15hr
- Metabolism: Extensive hepatic and intracellular
- Excretion: Mostly renal. Dialyzable.
Mechanism of Action
- Inhibits dihydrofolate reductase--> blocks DNA synthesis and thus, cellular replication/repair