An antifolate is a type of drug commonly used during cancer chemotherapy. It belongs to the antineoplastic class of drugs. Although antifolates cause a number of negative side effects, they remain a popular treatment because they slow the growth and production of cancer cells.
Aminopterin (AMT) was the first antifolate used to treat cancer. It was also the first modern cancer treatment and spawned methotrexate (MXT), the most commonly used antifolate. AMT successfully put pediatric leukemia patients in remission, but it had severe side effects. MXT quickly replaced AMT because it has a lower level of toxicity. Other types of antifolates exist, but MXT remains the most widely used for many types of cancer.
Antifolates function by preventing or slowing the growth of cancer cells. Folates are responsible for the production and maintenance of new cells. An antifolate causes a folate deficiency that slows the folate metabolism, preventing the rapid growth, division, and production of cancer cells. Unfortunately, antifolates can interfere with the creation of nucleotides, which play a fundamental role in metabolism.
The side effects associated depend on the type of drug. Some of the common side effects include nausea, vomiting, diarrhea, and rashes. Weight loss is also a predominate symptom experienced by those who receive the chemotherapy drugs. Other effects, such as anemia and inflammation of the skin, throat, and mouth, also are associated with more than one type of treatment.
Some effects of antifolate are more serious and cause more discomfort than others. It is not uncommon for bone marrow to be adversely affected, which can be dangerous. One type of antifolate, known as pemetrexed, may cause numbness is the hands and feet, chest pain, shortness of breath, fever, and depression. Other types may increase the risk of developing diseases such as pulmonary fibrosis and hepatitis. The likelihood of infections, bruising, and kidney or liver damage may increase as well.
The inclusion of antifolates during chemotherapy can help with many types of cancer, and cancer type may influence the choice of drugs. For example, MXT is especially useful for uterine cancer, while pemextred is particularly effective for treating lung cancers. Lometrexol is a type of antifolate that successfully treats breast, colon, pancreatic, head, neck, and lung cancers.
Medical professionals may consider a number of factors before choosing an antifolate for cancer chemotherapy. The age of the patient may play a part in the decision-making process, as young patients react better to some drugs than older patients do. Pre-existing medical problems also may be important because antifolates can worsen some health issues and cause dangerous drug interactions.