B.1. Methotrexate (also referred to
as amethopterin)
Methotrexate
has been used for treating cancer and autoimmune diseases for many years.
Although it has been off-patent for many years, it is still very highly
prescribed.
Methotrexate
is an antimetabolite
that interferes with the use of folic acid. As shown in Figure 1.6, the
structures of methotrexate and folic acid are strikingly similar. Because folic
acid is essential for the synthesis and repair of DNA, especially during cell
growth and division, it is logical that methotrexate interferes with the growth
of cancer cells.
Methotrexate is cytotoxic and has a
wide range of potential side effects including myelosuppression and mucositis.
Methotrexate is also highly teratogenic and should not be taken by women during
pregnancy or expected to be pregnant. It is generally true that no chemotherapy
is given for pregnant women and, for women of child-bearing age, precaution
must be taken.
Fig. 1.6 Structures of methotrexate (left) and folic
acid (right)
Sometimes, folic acid is used to
reduce the side effects of methotrexate. However, folic acid could act as an
antidote to methotrexate, therefore, it is better to use folic acid on the off
days during methotrexate treatment.
© Jiajiu Shaw, 2018
Disclaimer: This blog is written solely for informational purposes. It does not constitute the practice of any medical, nursing or other medical professional health care advice, diagnosis, or treatment. All contents posted are extracted from the book, "SIDE EFFECTS OF CHEMOTHERAPY AND RADIOTHERAPY", prepared by Dr. Jiajiu Shaw, Dr. Frederick Valeriote, and Dr. Ben Chen.
