Types of Chemotherapy Drugs
Chemotherapy as you know is a mode of treatment to treat all kinds of cancer. Though the drugs used here vary. These drugs can be classified according to their working, chemical structure and their action when used as combination with other drugs. There are some drugs that are derived from the same plant and thus they are grouped together while there are some that belong to more than one thus they are classified differently. Classification of these drugs helps for a better combination of use of these drugs in chemotherapy.
How are these drugs classified?
These drugs are classified according to their chemical structure and the way they act upon the cancerous affected cells on your body.
Alkylating agents : These agents were the first to be used to treat various kinds of cancer. They were known to attack the DNA structure of the cells thus preventing the replication of cancer cells in the body. These alkylating agents work better where the growth of cancer cells is slow. The alkylating agents commonly used to treat cancer are thiotepa, cyclophosphamide, busulfan and chlorambucil.Antimetabolites : These are chemotherapy drugs known to replace the natural DNA molecular substances thus altering the function of the enzymes that are required for carrying out the protein synthesis as well as the metabolic activities of the body. These are known to prevent the much required nutrients from reaching the cells thus starving these effected cells and killing them. These agents are at their most effective action when they undergo S-phase of cell division.
What is S-phase?
S-phase is a phase when the cells are known to undergo DNA synthesis or rather when the cells undergo new cell generation. Antimetabolites are known to attack these cells when they are undergoing the rapid growth and division of cell structure. Drugs that help destroy the growth of these cells are pyrimidine antagonists, folate antagonists and purine antagonists.
Antitumor antibiotic : These are yet another type of chemotherapy drugs that don’t work for any specific cell cycle. These drugs are known to bind the DNA and prevent the RNA synthesis whose basic function is to provide the much needed proteins that are needed for the survival of these cells. Commonly used antitumor antibiotic drugs are doxorubicin, bleomycin and mitoxantrone. These drugs are administered orally, intravenously, topically as well as intramuscularly depending upon the type of cancer and chemotherapy used. Here the dosage if low has not shown much effective results as in case of higher dosage of the drugs used.
Plant alkaloids and their usefulness in treating cancer :
Plant alkaloids are yet another type of chemotherapy drugs used to treat cancer and as the name goes these drugs are plant derivatives. These drugs are used to prevent the cancer cells from self division of cells and some of these drugs are known to act throughout the cell structure while some are known to be effective in a particular cell cycle i.e. the S and M phases of cell cycle. The most commonly used plant alkaloids to treat cancer are doxorubicin, mitomycin and actinomycin D.