Đăng xuất
Symptoms: Toxicity of methotrexate mainly affects the hematopoietic and gastrointestinal systems. Symptoms include leukopenia, thrombocytopenia, anemia, pancytopenia, neutropenia, bone marrow depression, mucositis, stomatitis, oral ulceration, nausea, vomiting, gastrointestinal ulceration, and gastrointestinal bleeding. Some patients showed no signs of overdose.
There are reports of death due to sepsis, septic shock, renal failure, and aplastic anemia.
Cases of overdose have been reported, sometimes fatal, due to erroneous daily intake instead of weekly intake of oral methotrexate. In these cases, symptoms that have been commonly reported are hematological and gastrointestinal reactions.
Treatment: Calcium folate is the specific antidote for neutralizing the toxic undesirable effects of methotrexate.
In cases of accidental overdose, a dose of calcium folinate equal to or higher than the offending dose of methotrexate should be administered intravenously or intramuscularly within one hour Observation of serum methotrexate concentrations is relevant in determining the right dose of calcium folate and the duration of the therapy.
In cases of massive overdose, hydration, and urinary alkalisation may be necessary to prevent precipitation of methotrexate and/or its metabolites in the renal tubules. Neither hemodialysis nor peritoneal dialysis has been shown to improve methotrexate elimination. Effective clearance of methotrexate has been reported with acute, intermittent hemodialysis using a high flux dialyzer.
