Can Methotrexate from 3 years ago trigger a reaction in blood cells due to toxins?

Question

Methotrexate is one of the drugs that can cause homosystiene, blood cell abnormalities and bone marrow problems Has been 3 years since last shot. Is it the cause of my Lymphocyte cells and Macrocytosis to trigger a serious allergy to a toxin that was never allergic to before, with horrible symptoms, Rapid weight loss, rhitinitus, sinus infections, no menses for 5 months while in the contaminated building. Once out of store, 2 wekks, blood got better, and got menses. Gaining back weight noe

Answer 1

Adverse effects
Possible side effects can include anemia, neutropenia, increased risk of bruising, nausea and vomiting, dermatitis and diarrhea. A small percentage of patients develop hepatitis, and there is an increased risk of pulmonary fibrosis.

The higher doses of methotrexate often used in cancer chemotherapy can cause toxic effects to the rapidly-dividing cells of bone marrow and gastrointestinal mucosa. The resulting myelosuppression and mucositis are often prevented (termed methotrexate "rescue") by using folinic acid supplements (not to be confused with folic acid).

Methotrexate is a highly teratogenic drug and categorized in Pregnancy Category X by the FDA. Women must not take the drug during pregnancy, if there is a risk of becoming pregnant, or if they are breastfeeding. Men who are trying to get their partner pregnant must also not take the drug. To engage in any of these activities (after discontinuing the drug), women must wait until the end of a full ovulation cycle and men must wait three months.

There is a risk of a severe adverse reaction if penicillin is prescribed alongside methotrexate.

Mode of action
Methotrexate competitively and reversibly inhibits dihydrofolate reductase (DHFR), an enzyme that is part of the folate synthesis metabolic pathway. The affinity of methotrexate for DHFR is about one thousand-fold that of folate for DHFR. Dihydrofolate reductase catalyses the conversion of dihydrofolate to the active tetrahydrofolate. Folic acid is needed for the de novo synthesis of the nucleoside thymidine, required for DNA synthesis. Methotrexate, therefore, inhibits the synthesis of DNA, RNA, thymidylates, and proteins.

Methotrexate is cell cycle S-phase selective, and has a greater negative effect on rapidly dividing cells (such as malignant and myeloid cells), which are replicating their DNA, and thus inhibits the growth and proliferation of these cells.

Lower doses of methotrexate have been shown to be very effective for the management of rheumatoid arthritis and psoriasis. In these cases inhibition of dihydrofolate reductase (DHFR) is not thought to be the main mechanism, rather the inhibition of enzymes involved in purine metabolism, leading to accumulation of adenosine, or the inhibition of T cell activation and suppression of intercellular adhesion molecule expression by T cells (Johnston et al., 2005) [2].

Answer 2

MTX has absoltely nothing to do with what you mentioned..
you might think that MTX would dampen any allergic reaction since it lowers the body immunity & its ability to form anibody & so its ability to react against any antigen ( & that what is allergy is).
However I will need much more data like age, associated conditions etc etc to tell you EXACTLY what is going on, so the best thing is to see your doctor who may refer you to an immunologist.
Good luck